Fakultät Informatik und Mathematik
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ELSI-Begleitforschung entwickelt sich zunehmend zu einem integralen Bestandteil von Forschungs- und Entwicklungsprojekten – nicht zuletzt dadurch, dass Drittmittelgeber wie die EU oder das BMBF in vielen Förderlinien explizit fordern, dass Technik wertebasiert entwickelt bzw., responsible research and innovation‘ (RRI) betrieben wird. Leitend ist hierbei der Gedanke, dass die Gestaltung von Technik alle Stakeholder-Interessen berücksichtigen soll; die Ermittlung dieser Interessen sowie die moralisch fundierte Balance zwischen widerstreitenden Interessen soll durch partizipative Verfahren erreicht werden. Dazu eignen sich ethische Leitlinien oder andere Kodifizierungen von Normen und Werten nur bedingt; in der Praxis werden anwendbare Verfahren benötigt. In den letzten Jahren wurden solche Verfahren entwickelt und bereits in der F&E-Praxis erprobt und eingesetzt. Drei (diskursethisch basierte) Verfahren, die kombiniert werden können, sollen vorgestellt werden.
SQL-on-Hadoop processing engines have become state-of-the-art in data lake analysis. However, the skills required to tune such systems are rare. This has inspired automated tuning advisors which profile the query workload and produce tuning setups for the low-level MapReduce jobs. Yet with highly dynamic query workloads, repeated re-tuning costs time and money in IaaS environments. In this paper, we focus on reducing the costs for up-front tuning. At the heart of our approach is the observation that a SQL query is compiled into a query plan of MapReduce jobs. While the plans differ from query to query, single jobs tend to be similar between queries. We introduce the notion of the code signature of a MapReduce job and, based on this, our concept of job similarity. We show that we can effectively recycle tuning setups from similar MapReduce jobs already profiled. In doing so, we can leverage any third-party tuning adviser for MapReduce engines. We are able to show that by recycling tuning setups, we can reduce the time spent on profiling by 50% in the TPC-H benchmark.
This article revisits an analysis on (in)accuracies of time series averaging under dynamic time warping (dtw) conducted by Niennattrakul and Ratanamahatana [16]. They proposed a correctness-criterion for dtw-averages and postulated that dtw-averages can drift out of the cluster of time series to be averaged. They claimed that dtw-averages are inaccurate if they violate the correctness-criterion or suffer from the drift-out phenomenon. Furthermore, they conjectured that such inaccuracies are caused by the lack of triangle inequality. In this article, we show that a rectified version of the correctness-criterion is unsatisfiable and that the concept of drift-out is geometrically and operationally inconclusive. Satisfying the triangle inequality is insufficient to achieve correctness and unnecessary to overcome the drift-out phenomenon. We place the concept of drift-out on a principled basis and show that Fréchet means never drift out. The adjusted drift-out is a way to test to which extent an approximated dtw-average is coherent. Empirical results show that approximations obtained by the state-of-the-art averaging methods are incoherent in over a third of all cases.
The sample mean is one of the most fundamental concepts in statistics with far-reaching implications for data mining and pattern recognition. Household load profiles are compared to the aggregated levels more intermittent and a specific error measure based on local permutations has been proposed to cope with this when comparing profiles. We formally describe a distance based on this error, the local permutation invariant (LPI) distance, and introduce the sample mean problem in the LPI space. An existing exact solution has exponential complexity and is only tractable for very few profiles. We propose three subgradient-based approximation algorithms and compare them empirically on 100 households of the CER dataset. We find that stochastic subgradient descent can approximate the mean best, while the majorize-minimize mean is a good compromise for applications as no hyperparameter-tuning is needed. We show how the algorithms can be used in forecasting and clustering to achieve more appropriate results than by using the arithmetic mean.
The literature postulates that the dynamic time warping (dtw) distance can cope with temporal variations but stores and processes time series in a form as if the dtw-distance cannot cope with such variations. To address this inconsistency, we first show that the dtw-distance is not warping-invariant—despite its name and contrary to its characterization in some publications. The lack of warping-invariance contributes to the inconsistency mentioned above and to a strange behavior. To eliminate these peculiarities, we convert the dtw-distance to a warping-invariant semi-metric, called time-warp-invariant (twi) distance. Empirical results suggest that the error rates of the twi and dtw nearest-neighbor classifier are practically equivalent in a Bayesian sense. However, the twi-distance requires less storage and computation time than the dtw-distance for a broad range of problems. These results challenge the current practice of applying the dtw-distance in nearest-neighbor classification and suggest the proposed twi-distance as a more efficient and consistent option.
Averaging time series under dynamic time warping is an important tool for improving nearest-neighbor classifiers and formulating centroid-based clustering. The most promising approach poses time series averaging as the problem of minimizing a Fréchet function. Minimizing the Fréchet function is NP-hard and so far solved by several heuristics and inexact strategies. Our contributions are as follows: we first discuss some inaccuracies in the literature on exact mean computation in dynamic time warping spaces. Then we propose an exponential-time dynamic program for computing a global minimum of the Fréchet function. The proposed algorithm is useful for benchmarking and evaluating known heuristics. In addition, we present an exact polynomial-time algorithm for the special case of binary time series. Based on the proposed exponential-time dynamic program, we empirically study properties like uniqueness and length of a mean, which are of interest for devising better heuristics. Experimental evaluations indicate substantial deficits of state-of-the-art heuristics in terms of their output quality.
In diesem Talk blicken Prof. Dr. Wolfgang Mauerer und Ralf Ramsauer unter die Haube des verteilten Versionskontrollsystems Git. Neben einer genauen Beschreibung der Strukturen und Plumbing APIs, mit denen Git intern Commits erzeugt und verknüpft, gehen die Vortragenden auch auf nützliche Features und Standards ein, welche die Kollaborition in großen Open-Source Projekten erleichtern.
As a result of the enormous growth in data traffic for autonomous driving, the conventional in-vehicle network is no longer sufficient and requires new types of network concepts in a vehicle. This part of the automobile is known as the next generation communication network. Since the new car-systems can be extended by various services at any time, the network must adapt dynamically to new requirements wherever possible. For example, data flow must be configured dynamically between new services. Also data rates will be much higher in the future than today. This is one of the main reasons why we need to search for new technologies for data transfer in vehicles. This is based on an in-vehicle ethernet network. The process of configuring networks automatically has been discussed several times in recent years. One of the next steps is verifying and validating the automatic configuration process during the development of the new communication network. This research paper identifies several ways to ensure the automatically generated network configuration leads to a secure system. To achieve that, other parts of the company’s enterprise IT architecture and network technologies, the conventional vehicle network and other options for verification and validation are analysed
The Spoken Wikipedia Corpus collection: Harvesting, alignment and an application to hyperlistening
(2019)
Spoken corpora are important for speech research, but are expensive to create and do not necessarily reflect (read or spontaneous) speech ‘in the wild’. We report on our conversion of the preexisting and freely available Spoken Wikipedia into a speech resource. The Spoken Wikipedia project unites volunteer readers of Wikipedia articles. There are initiatives to create and sustain Spoken Wikipedia versions in many languages and hence the available data grows over time. Thousands of spoken articles are available to users who prefer a spoken over the written version. We turn these semi-structured collections into structured and time-aligned corpora, keeping the exact correspondence with the original hypertext as well as all available metadata. Thus, we make the Spoken Wikipedia accessible for sustainable research. We present our open-source software pipeline that downloads, extracts, normalizes and text–speech aligns the Spoken Wikipedia. Additional language versions can be exploited by adapting configuration files or extending the software if necessary for language peculiarities. We also present and analyze the resulting corpora for German, English, and Dutch, which presently total 1005 h and grow at an estimated 87 h per year. The corpora, together with our software, are available via http://islrn.org/resources/684-927-624-257-3/. As a prototype usage of the time-aligned corpus, we describe an experiment about the preferred modalities for interacting with information-rich read-out hypertext. We find alignments to help improve user experience and factual information access by enabling targeted interaction.
Speech-based interactive systems, such as virtual personal assistants, inevitably use complex architectures, with a multitude of modules working in series (or less often in parallel) to perform a task (e.g., giving personalized movie recommendations via dialog). Add modules for evoking and sustaining sociability with the user and the accumulation of processing latencies through the modules results in considerable turn-taking delays. We introduce incremental speech processing into the generation pipeline of the system to overcome this challenge with only minimal changes to the system architecture, through partial underspecification that is resolved as necessary. A user study with a sociable movie recommendation agent objectively diminishes turn-taking delays; furthermore, users not only rate the incremental system as more responsive, but also rate its recommendation performance as higher.
Ellipses denote the omission of one or more grammatically necessary phrases. In this paper, we will demonstrate how to identify such ellipses as a rhythmical pattern in modern and postmodern free verse poetry by using data from lyrikline which contain the corresponding audio recording of each poem as spoken by the original author. We present a feature engineering approach based on literary analysis as well as a neural networks based approach for the identification of ellipses within the lines of a poem. A contrast class to the ellipsis is defined from poems consisting of complete and correct sentences. The feature-based approach used features derived from a parser such as verb, comma, and sentence ending punctuation. The classifier of neural networks is trained on the line level to integrate the textual information, the spoken recitation, and the pause information between lines, and to integrate information across the lines within the poem. A statistic analysis of poet's gender showed that 65% of all elliptical poems were written by female poets. The best results, calculated by the weighted F-measure, for the classification of ellipsis with the contrast class is 0.94 with the neural networks based approach. The best results for classification of elliptical lines is 0.62 with the feature-based approach.
This work aims to discern the poetics of concrete poetry by using a corpus-based classification focusing on the two most important techniques used within concrete poetry: semantic decomposition and syntactic permutation. We demonstrate how to identify concrete poetry in modern and postmodern free verse. A class contrasting to concrete poetry is defined on the basis of poems with complete and correct sentences. We used the data from lyrikline, which contain both the written as well as the spoken form of poems as read by the original author. We explored two approaches for the identification of concrete poetry. The first is based on the definition of concrete poetry in literary theory by the extraction of various types of features derived from a parser, such as verb, noun, comma, sentence ending, conjunction, and asemantic material. The second is a neural network-based approach, which is theoretically less informed by human insight, as it does not have access to features established by scholars. This approach used the following inputs: textual information and the spoken recitation of poetic lines as well as information about pauses between lines. The results based on the neural network are more accurate than the feature-based approach. The best results, calculated by the weighted F-measure, for the classification of concrete poetry vis-à-vis the contrasting class is 0.96
Translation systems aim to perform a meaning-preserving conversion of linguistic material (typically text but also speech) from a source to a target language (and, to a lesser degree, the corresponding socio-cultural contexts). Dubbing, i.e., the lip-synchronous translation and revoicing of speech adds to this constraints about the close matching of phonetic and resulting visemic synchrony characteristics of source and target material. There is an inherent conflict between a translation’s meaning preservation and ‘dubbability’ and the resulting trade-off can be controlled by weighing the synchrony constraints. We introduce our work, which to the best of our knowledge is the first of its kind, on integrating synchrony constraints into the machine translation paradigm. We present first results for the integration of synchrony constraints into encoder decoder-based neural machine translation and show that considerably more ‘dubbable’ translations can be achieved with only a small impact on BLEU score, and dubbability improves more steeply than BLEU degrades.
Data-based analyses are becoming more and more common in the Digital Humanities and tools are needed that focus human efforts on the most interesting and important aspects of exploration, analysis and annotation by using active machine learning techniques. We present our ongoing work on a tool that supports classification tasks for spoken documents (in our case: read-out post-modern poetry) using a neural networks-based classification backend and a web-based exploration and classification environment.
The following article considers the need to integrate social aspects into the Master Production Scheduling. This is justified by the demand for sustainable business processes and the previously neglected social dimension, which is also reflected in the development of working conditions. The linear optimization model for Master Production Scheduling outlined in connection with aspects of Human Resource Requirements Planning offers an approach to reduce this research gap and underlines the urgency of long-term planning and control of employee burdens. For companies, this results in a Decision Support System through the evaluation of measures to improve working conditions.
More than 30 years after its first implementation, IT outsourcing (ITO) is unanimously considered a critical component of corporate strategy for private and public institutions alike. While implementations of ITO around the world share some common characteristics like typical reasons for outsourcing, key success factors, or dimensions along which they can be classified, extant research also points to regional differences. However, research on this topic, specifically regarding pivotal contract features like contract value, contract length, or pricing methods, is still in its infancy, and quantitative analyses on the subject are particularly scarce. We address this research gap by analyzing data on 14,917 ITO contracts closed between 2007 and 2017 through the lens of cultural regions and three statistical methods. The contribution of our paper is threefold. First, our descriptive analysis points to globally decreasing contract lengths and contract values, confirming previous studies and practice reports. Second, an ANOVA with independent post-hoc testing provides quantitative support for the degree of dissimilarity among individual regions in pivotal ITO contract features. Finally, our quantitative replication of a previous study identifies culture-induced regional differences between USA and Japan regarding the effect of influence factors on ITO contract features
Der Eigenständigkeitsanspruch der Maschinenethik steht und fällt mit der Frage, ob man autonome Maschinen als moralische Agenten betrachten kann. Zur Beantwortung dieser Frage wird untersucht, unter welchen Voraussetzungen man Maschinen als moralische Agenten betrachten und ob man Maschinen Autonomie und Verantwortungsfähigkeit zusprechen kann. Die Autoren kommen zu dem Schluss, dass es in absehbarer Zukunft zwar keine „moralische Maschinen“ geben mag, es aber Aufgabe der Maschinenethik sein sollte, Maschinen so zu gestalten, dass sie als quasi-moralische Akteure akzeptiert werden können. Dabei dürfen jedoch jene menschlichen Akteure, die entsprechende Maschinen gestalten, entwickeln, bauen und nutzen, nicht aus ihrer Verantwortung entlassen werden.
A basic task in the design of a robotic production cell is the relative placement of robot and workpiece. The fundamental requirement is that the robot can reach all process positions; only then one can think further optimization. Therefore an algorithm that automatically places an object into the workspace is very desirable. However many iterative optimization algorithms cannot guarantee that all intermediate steps are reachable, resulting in complicated procedures. We present a novel approach which extends a robot by a virtual prismatic joint - which measures the distance to the workspace - such that any TCP frames are reachable. This allows higher order nonlinear programming algorithms to be used for placement of an object alone as well as the optimal placement under some differentiable criterion.
Einleitung:
Die ubiquitäre Durchdringung mit digitaltechnischen Applikationen und den damit einhergehenden Einflüssen auf organisationale Strukturen, führt insbesondere im hochsensiblen medizinischen Anwendungsbereich zur Notwendigkeit, einer aktiven Implementierungsgestaltung. Das zwischen den omnipräsenten Schlagwörtern Big Data (Analytics), Smart Technologies, Internet of Things oder Künstliche Intelligenz (KI) bestehende und für etwaige Implementierungsabwägungen bedeutsame korrelative Verhältnis, ist dabei nicht immer offensichtlich: Viele konzeptionelle Überlegungen aus früheren Ansätzen der KI manifestieren sich in den verschiedenen Digitalisierungstrends und Entwicklungstendenzen.
Methode:
Die intensive theoretische Auseinandersetzung mit Entwicklungslinien und inhaltlicher Reflektion von begleitenden Diskursen, kann im Rahmen der Auseinandersetzung mit KI-basierten Anwendungen und den An- wie auch Herausforderungen an deren Implementierung einen Weg eröffnen, ethische und soziale Aspekte heutiger KI-Entwicklungen (im Vortrag am Beispiel der KI-Nutzung in der medizinischen Diagnostik) zumindest teilweise daraus abzuleiten, besser zu verstehen und gegebenenfalls um neue Faktoren zu ergänzen.
Ergebnisse:
Die Gegenüberstellung früherer und heutiger KI-Debatten leistet dabei einen grundlegenden Beitrag zur Identifikation relevanter Wertebereiche, sowie zur Entwicklung erster vorläufiger Empfehlungen für die Gestaltung und den Einsatz von KI-Systemen in der Praxis und derart deren konstruktive Einbettung in existierende Organisationsstrukturen.
Diskussion:
Neben der Identifikation potentieller Stakeholder und möglicher Interessenslagen, eröffnet ein derart empirisch orientierter Zugang erste Einblicke in die, für die Hervorbringung und Implementierung medizintechnischer Applikationen notwendige normative Landschaft. Um hieraus jedoch, wie im Projekt „KI & Ethik“ angedacht, eine tentative ethische Leitlinien als Rahmengefüge des Einsatzes einer medizintechnischen Anwendung abzuleiten, gilt es ein solches Fundament um jeweilige, aus Stakeholder-Interviews gewonnene Perspektiven auf etwaige An- und Herausforderungen an eine Implementierung, aber auch hinsichtlich deren Nutzungserwartungen zu erweitern.
The German National Educational Panel Study (NEPS) was set up to provide an empirical basis for longitudinal analyses of individuals’ educational careers and competencies and how they unfold over the life course in relation to family, formal educational institutions, and private life. Educational developments and decisions over the life span are being tracked in six starting cohorts as a foundation for characterizing and analyzing educational processes. These six starting cohorts include newborns, Kindergarten children, secondary school children (5th and 9th grade), first-year undergraduate students, and adults. Because access to the target population in several starting cohorts was gained via educational institutions such as Kindergartens and schools, multistage sampling approaches were implemented that reflect the clustered structure of the target populations. Samples in individual contexts, such as those in the adult and newborn cohorts, were established via register-based stratified cluster approaches. This chapter briefly reviews the designs of the implemented sampling strategies for each established starting cohort and provides information on the levels of attrition in the panel development.
A new vision in semantic big data processing is to create enterprise data hubs, with a 360° view on all data that matters to a corporation. As we discuss in this paper, a new generation of multi-model database systems seems a promising architectural choice for building such scalable, non-native triple stores. In this paper, we first characterize this new generation of multi-model databases. Then, discussing an example scenario, we show how they allow for agile and flexible schema management, spanning a large design space for creative and incremental data modelling. We identify the challenge of generating sound triple-views from data stored in several, interlinked models, for SPARQL querying. We regard this as one of several appealing research challenges where the semantic big data and the database architecture community may join forces.
Recently, the semantics of the JSON Schema format, a de-facto standard for JSON schema declarations, has been formalized. It turns out that JSON Schema is a surprisingly complex schema language based on an open document semantics. In this paper, we present a first empirical analysis of a curated collection of real-world JSON Schemas. Knowing what real JSON Schemas are like (to borrow from a title of a related study on DTDs) helps practitioners and researchers in making realistic assumptions when building tools for JSON Schema processing.
Gewichtung
(2019)
Ziel einer Analyse quantitativer Daten ist die Verallgemeinerung der Stichprobenergebnisse auf die interessierende Grundgesamtheit (Häder/Häder, Kapitel 22 in diesem Band). Tatsächlich unterscheiden sich Stichproben in bestimmter Hinsicht aber fast immer von der Grundgesamtheit; sei es durch ein geplantes „Oversampling“ einer bestimmten Teilpopulation (die Genauigkeit einer Schätzung wird im Wesentlichen von der Fallzahl in der Stichprobe bestimmt, weshalb seltene Teilpopulationen, für die valide Schätzungen möglich sein sollen, mit einem größeren Auswahlsatz in die Erhebung aufgenommen werden) oder durch selektiven Nonresponse (Engel/Schmidt, Kapitel 27 in diesem Band). Viele Befragungen weisen etwa einen so genannten „Mittelschichtsbias“ auf; Personen mit mittlerem bis gehobenem Bildungsniveau (gemessen durch den höchsten Schulabschluss) zeigen sich am öftesten bereit, an Umfragen teilzunehmen, sie sind in den Erhebungsdaten daher überrepräsentiert.
We demonstrate MigCast, a tool-based advisor for exploring data migration strategies in the context of developing NoSQL-backed applications. Users of MigCast can consider their options for evolving their data model along with legacy data already persisted in the cloud-hosted production data-base. They can explore alternative actions as the financial costs are predicted respective to the cloud provider chosen. Thereby they are better equipped to assess potential consequences of imminent data migration decisions. To this end, MigCast maintains an internal cost model, taking into account characteristics of the data instance, expected work-load, data model changes, and cloud provider pricing models. Hence, MigCast enables software project stakeholders to remain in control of the operative costs and to make informed decisions evolving their applications.
In this paper, we raise the question how data architects model their data for processing in Apache Hive. This well-known SQL-on-Hadoop engine supports complex value relations, where attribute types need not be atomic. In fact, this feature seems to be one of the prominent selling points, e.g., in Hive reference books. In an empirical study, we analyze Hive schemas in open source repositories. We examine to which extent practitioners make use of complex value relations and accordingly, whether they write queries over complex types. Understanding which features are actively used will help make the right decisions in setting up benchmarks for SQL-on-Hadoop engines, as well as in choosing which query operators to optimize for.
There has been a lot of research been done in the domain of Wireless Sensor Networks in recent years. Nowadays, Wireless Sensor Networks are in operation in a wide range of different scenarios and applications, like energy management services, heat and water billing as well as smoke detectors. However, research and development will be continued in this domain. During the operation of such a network, software updates need to be done seldom. In contrast to this, software updates need to be done very frequently during development and testing for uploading a new firmware on umpteen nodes. In this paper, we examine such a software update for a particular, but popular and often used sensor network platform. There are already interesting research papers about the process of updating sensor nodes. Our specific focus relies on the technical part of such an update process. We will argue why these already existing update processes do not cover our defiances. The objective of our software update protocol is to enable the developer to update many nodes in a reliable and very fast fashion during the development and testing process. For this reason, energy consumption is considered only marginally. We do not need a multi-hop protocol, due to the fact that all devices are in range, e.g. in a laboratory. In this paper we survey well known update protocols and architectures for software updates in WSN, discuss the solutions and compare them to our approach. As a conclusion of our extensive simulation follows to sum up that the developed protocols do a fast and scalable as well as a reliable update.
A considerable corpus of research on software evolution focuses on mining changes in software repositories, but omits their pre-integration history. We present a novel method for tracking this otherwise invisible evolution of software changes on mailing lists by connecting all early revisions of changes to their final version in repositories. Since artefact modifications on mailing lists are communicated by updates to fragments (i.e., patches) only, identifying semantically similar changes is a non-trivial task that our approach solves in a language-independent way. We evaluate our method on high-profile open source software (OSS) projects like the Linux kernel, and validate its high accuracy using an elaborately created ground truth. Our approach can be used to quantify properties of OSS development processes, which is an essential requirement for using OSS in reliable or safety-critical industrial products, where certifiability and conformance to processes are crucial. The high accuracy of our technique allows, to the best of our knowledge, for the first time to quantitatively determine if an open development process effectively aligns with given formal process requirements.
Machine learning (ML) based decision making is becoming commonplace. For persons affected by ML-based decisions, a certain level of transparency regarding the properties of the underlying ML model can be fundamental. In this vision paper, we propose to issue consumer labels for trained and published ML models. These labels primarily target machine learning lay persons, such as the operators of an ML system, the executors of decisions, and the decision subjects themselves. Provided that consumer labels comprehensively capture the characteristics of the trained ML model, consumers are enabled to recognize when human intelligence should supersede artificial intelligence. In the long run, we envision a service that generates these consumer labels (semi-)automatically. In this paper, we survey the requirements that an ML system should meet, and correspondingly, the properties that an ML consumer label could capture. We further discuss the feasibility of operationalizing and benchmarking these requirements in the automated generation of ML consumer labels.
Machine learning experts prefer to think of their input as a single, homogeneous, and consistent data set. However, when analyzing large volumes of data, the entire data set may not be manageable on a single server, but must be stored on a distributed file system instead. Moreover, with the pressing demand to deliver explainable models, the experts may no longer focus on the machine learning algorithms in isolation, but must take into account the distributed nature of the data stored, as well as the impact of any data pre-processing steps upstream in their data analysis pipeline. In this paper, we make the point that even basic transformations during data preparation can impact the model learned, and that this is exacerbated in a distributed setting. We then sketch our vision of end-to-end explainability of the model learned, taking the pre-processing into account. In particular, we point out the potentials of linking the contributions of research on data provenance with the efforts on explainability in machine learning. In doing so, we highlight pitfalls we may experience in a distributed system on the way to generating more holistic explanations for our machine learning models.
IOT Backdoors in Cars
(2019)
Connecting cheap IoT devices to the safety-critical network of a car can be an extremely bad idea, but at least it allows us to hack together our own automotive gadget. This talk explains the complete procedure involved in transforming a cheap OBD GSM dongle designed for fleet management into a open source automotive hacking tool. First, the hardware reverse engineering is demonstrated, showing how each component is interconnected and working together. With this knowledge, it was possible to capture the communication of the GSM module and understand the OTA protocol used by this dongle, which can be used to extract the firmware. A quick reverse engineering of the software will show that no cryptographic authentication is used for the OTA updates, and therefore a pirate GSM BTS can be used to obtain remote code execution. After that, a new open source firmware is written for the device, which can easily be extended and controlled remotely with the LUA scripting language. Examples on how hacking this dongle remotely can affect the safety of the driver will be also given.
Background and objective:
In this work, we present a systematic review concerning the recent enabling technologies as a tool to the diagnosis, treatment and better quality of life of patients diagnosed with Parkinson's Disease (PD), as well as an analysis of future trends on new approaches to this end.
Methods:
In this review, we compile a number of works published at some well-established databases, such as Science Direct, IEEEXplore, PubMed, Plos One, Multidisciplinary Digital Publishing Institute (MDPI), Association for Computing Machinery (ACM), Springer and Hindawi Publishing Corporation. Each selected work has been carefully analyzed in order to identify its objective, methodology and results.
Results:
The review showed the majority of works make use of signal-based data, which are often acquired by means of sensors. Also, we have observed the increasing number of works that employ virtual reality and e-health monitoring systems to increase the life quality of PD patients. Despite the different approaches found in the literature, almost all of them make use of some sort of machine learning mechanism to aid the automatic PD diagnosis.
Conclusions:
The main focus of this survey is to consider computer-assisted diagnosis, and how effective they can be when handling the problem of PD identification. Also, the main contribution of this review is to consider very recent works only, mainly from 2015 and 2016.
This is a report on a course taught at OTH Regensburg in the summer term of 2018. The students in this course built their own SQL-on-Hadoop engine as a term project in just 8 weeks. miniHive is written in Python and compiles SQL queries into MapReduce workflows. These are then executed on Hadoop. miniHive performs generic query optimizations (selection and projection pushdown, or cost-based join reordering), as well as MapReduce-specific optimizations.
The course was taught in English, using a flipped classroom model. The course material was mainly compiled from third-party teaching videos. This report describes the course setup, the miniHive milestones, and gives a short review of the most successful student projects.
A Hybrid Solution Method for the Capacitated Vehicle Routing Problem Using a Quantum Annealer
(2019)
he Capacitated Vehicle Routing Problem (CVRP) is an NP-optimization problem (NPO) that has been of great interest for decades for both, science and industry. The CVRP is a variant of the vehicle routing problem characterized by capacity constrained vehicles. The aim is to plan tours for vehicles to supply a given number of customers as efficiently as possible. The problem is the combinatorial explosion of possible solutions, which increases superexponentially with the number of customers. Classical solutions provide good approximations to the globally optimal solution. D-Wave's quantum annealer is a machine designed to solve optimization problems. This machine uses quantum effects to speed up computation time compared to classic computers. The problem on solving the CVRP on the quantum annealer is the particular formulation of the optimization problem. For this, it has to be mapped onto a quadratic unconstrained binary optimization (QUBO) problem. Complex optimization problems such as the CVRP can be translated to smaller subproblems and thus enable a sequential solution of the partitioned problem. This work presents a quantum-classic hybrid solution method for the CVRP. It clarifies whether the implementation of such a method pays off in comparison to existing classical solution methods regarding computation time and solution quality. Several approaches to solving the CVRP are elaborated, the arising problems are discussed, and the results are evaluated in terms of solution quality and computation time.
To support a rational and efficient use of electrical energy in residential and industrial environments, Non-Intrusive Load Monitoring (NILM) provides several techniques to identify state and power consumption profiles of connected appliances. Design requirements for such systems include a low hardware and installations costs for residential, reliability and high-availability for industrial purposes, while keeping invasive interventions into the electrical infrastructure to a minimum. This work introduces a reference hardware setup that allows an in depth analysis of electrical energy consumption in industrial environments. To identify appliances and their consumption profile, appropriate identification algorithms are developed by the NILM community. To enable an evaluation of these algorithms on industrial appliances, we introduce the Laboratory-measured IndustriaL Appliance Characteristics (LILAC) dataset: 1302 measurements from one, two, and three concurrently running appliances of 15 appliance types, measured with the introduced testbed. To allow in-depth appliance consumption analysis, measurements were carried out with a sampling rate of 50 kHz and 16-bit amplitude resolution for voltage and current signals. We show in experiments that signal signatures, contained in the measurement data, allows one to distinguish the single measured electrical appliances with a baseline machine learning approach of nearly 100% accuracy.
Parkinson's disease (PD) is a neurodegenerative disease that affects millions of people worldwide, causing mental and mainly motor dysfunctions. The negative impact on the patient's daily routine has moved the science in search of new techniques that can reduce its negative effects and also identify the disease in individuals. One of the main motor characteristics of PD is the hand tremor faced by patients, which turns out to be a crucial information to be used towards a computer-aided diagnosis. In this context, we make use of handwriting dynamics data acquired from individuals when submitted to some tasks that measure abilities related to writing skills. This work proposes the application of recurrence plots to map the signals onto the image domain, which are further used to feed a Convolutional Neural Network for learning proper information that can help the automatic identification of PD. The proposed approach was assessed in a public dataset under several scenarios that comprise different combinations of deep-based architectures, image resolutions, and training set sizes. Experimental results showed significant accuracy improvement compared to our previous work with an average accuracy of over 87%. Moreover, it was observed an improvement in accuracy concerning the classification of patients (i.e., mean recognition rates above to 90%). The promising results showed the potential of the proposed approach towards the automatic identification of Parkinson's disease.
Internet of Thing (IoT) and Smart Grid (SG) are separate technologies. The digital transformation of the energy industry and the increasing digitalization in the private sector connect these technologies. Currently in Germany, the SG is under construction. In order to use future innovative services, SG and IoT must be combined. For this, we connect the SG Infrastructure with the IoT. A potential insecure device and network (IoT) should be able to transfer data to and from a critical infrastructure (SG). Open research question in this context are the security requirements architecture SG and IoT and the mechanism for authentication and authorisation in future application (SG and IoT). Due to the increasing networking of the systems (SG and IoT) new threats and attack vectors arise. The attacks to the architecture influence the target of authenticity, security and privacy. For the security analysis we focus on two communication points: the communication between the smart meter gateway, and the IoT device. In our example, a connected charging station with cloud services is connected with a SG infrastructure. To create a really smart service, the charging station needs a connection to the SG to get the current amount of renewable energy in the grid. With this two connections, new threats emerge. A security analysis over all the connections, including the vulnerability and the ability of an attacker, is developed in this paper. The analysis shows us challenges of the communication between IoT and SG. For this, we defined technical and organizational requirements for authentication and authorization. Current authentication and authorization mechanisms are no longer sufficient for the defined requirements. We present the Role-based trust model for Safety-critical Systems for these defined requirements. The new trust model is integrated into a role-based access control model. It defines data classes, which separate the sensitive and non-sensitive information.
SIM SIMulator
(2019)
Der Vortrag präsentierte ein Tool, das die Simulation einer SIM-Karte durch einen Standard-Mikrocontroller ermöglicht. Mit diesem Täuschungsmanöver kann die Authentifizierung des 3G-Mobilfunkstandards seitens der SIM-Karte umgangen werden. Tritt zusätzliche Hardware hinzu, die eine 3G-Basisstation vortäuscht, lässt sich eine Man-in-the-Middle-Attacke im 3G-Netz durchführen.
In diesem Szenario ist es möglich, die sensiblen Kommunikationsdaten, also den gesamten Datenverkehr beispielsweise zwischen einem Pkw und den Backend-Servern des Herstellers, auszulesen und zu untersuchen. Zudem eignet sich das Tool zum Pentesten von Modems oder SIM- beziehungsweise Smartcard-Applikationen. Der komplette Aufbau des sogenannten SIMulators ist als Open-Source-Software frei verfügbar und auf GitHub abrufbar.
Cloud Computing (CC), Internet of Thing (IoT) and Smart Grid (SG) are separate technologies. The digital transformation of the energy industry and the increasing digitalization in the private sector connect these technologies. At the moment, CC is used as a service provider for IoT. Currently in Germany, the SG is under construction and a cloud connection to the infrastructure has not been implemented yet. To build the SG cloud, the new laws for privacy must be implemented and therefore it’s important to know which data can be stored and distributed over a cloud. In order to be able to use future
innovative services, SG and IoT must be combined. For this, in
the next step we connect the SG infrastructure with the IoT.
A potential insecure device and network (IoT) should be able
to transfer data to and from a critical infrastructure (SG). In
detail, we focus on two different connections: the communication
between the smart meter switching box and the IoT device and the data transferred between the IoT and SG cloud. In our example, a connected charging station with cloud services is connected with a SG infrastructure. To create a really smart service, the charging station needs a connection to the SG to get the current amount of renewable energy in the grid. Private data, such as name, address and payment details, should not be transferred to the IoT cloud. With these two connections, new threads emerge. In this case, availability, confidentiality and integrity must be ensured. A risk analysis over all the cloud connections, including the vulnerability and the ability of an attacker and the resulting risk are developed in this paper.