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During the transition from conventional towards purely electrical, sustainable mobility, transitional technologies play a major part in the task of increasing adaption rates and decreasing range anxiety. Developing new concepts to meet this challenge requires adaptive test benches, which can easily be modified e.g. when progressing from one stage of development to the next, but also meet certain sustainability demands themselves. The system architecture presented in this paper is built around a service-oriented software layer, connecting a modular hardware layer for direct access to sensors and actuators to an extensible set of client tools. Providing flexibility, serviceability and ease of use, while maintaining a high level of reusability for its constituent components and providing features to reduce the required overall run time of the test benches, it can effectively decrease the CO2 emissions of the test bench while increasing its sustainability and efficiency.

Global urbanization for decades has led to unprecedented levels and growing demands for urban logistics. Thus, problems such as congestion, environmental noise, and urban sprawl are growing. As a result, many cities face problems of optimal decision-making regarding green and sustainable smart transportation systems and infrastructures. However, various possible measures and logistics concepts are available to improve urban logistics, while effects are unclear and difficult to predict. To meet the growing need for future-oriented decisions by city authorities, we developed a decision support system prototype that allows a strategic simulation-based evaluation of different logistics concepts regarding defined targets, e.g., pollutant emissions, traffic flow, space requirements, or economic efficiency on a city district level. An expert system for the strategic evaluation of logistics concepts on a city district level is integrated to achieve transferability and scalability.

Over the years multiple algorithms have been published in the field of artificial immune systems. In this paper we evaluate the effectiveness of different immune inspired algorithms when used in intrusion detection. The focus of the work is the usage of publicly available implementations and current data sets to increase repeatability and relevance to real world applications. Our results indicate a good fit of the immune theory to the problem of intrusion detection, with further research being needed.

Intrusion detection systems and other network security components detect security-relevant events based on policies consisting of rules. If an event turns out as a false alarm, the corresponding policy has to be adjusted in order to reduce the number of false positives. Modified policies, however, need to be tested before going into productive use. We present a visual analysis tool for the evaluation of security events and related policies which integrates data from different sources using the IF-MAP specification and provides a ���what-if��� simulation for testing modified policies on past network dynamics. In this paper, we will describe the design and outcome of a user study that will help us to evaluate our visual analysis tool.

This paper gives a survey of the state of the art in research considering artificial immune-based intrusion detection systems for smart grids. We considered publications of the last five years (2013–2018). The paper starts with a short introduction to the smart grid and artificial immune systems before presenting the noteworthy publications relevant to artificial immunity of smart grids. Finally we will classify the works into their main topics and show gaps in the current research.

Background Motion sensing input devices could provide a practical and low-cost alternative method for repeated range of motion measurements. This study aimed to assess the reliability, accuracy and time requirements of a motion sensing input device (Microsoft Kinect) for ROM measurements comparing it with goniometer based measurements and subjective estimation. Material and methods Full ROM was measured in 14 shoulder and elbow joints using the different methods. The order was randomly selected and each movement was measured twice. The results were recorded in degrees and the time measured in seconds. Results In general, there was a poor to moderate agreement between the Kinect system compared to the goniometer. There was a good agreement between the goniometer-based and the subjective technique. The Kinect-based technique showed excellent test-retest reliability. Conclusion The Kinect system showed good test-retest reliability, but lower accuracy compared to goniometer-based measurements. Improvements in patient positioning and measurement protocol standardization must be made before its implementation in clinical practice.

We investigate Anderson localization in a quasi–one-dimensional disordered system consisting of weakly coupled statistically independent channels. The dependence of the localization length on the coupling κ is shown to be singular: proportional to 1/|ln κ|. Numerical evidence is given for coupled random chains with different statistics of site potential. An analytical approach is developed based on the Fokker-Planck treatment of the coupled stationary Schrodinger equations with Gaussian delta-correlated potentials.

OSGi is a popular Java-based platform, which has its roots in the area of embedded systems. However, nowadays it is used more and more in enterprise systems. To fit this new application area, OSGi has recently been extended with the Remote Services specification. This specification enables distribution, which OSGi was previously lacking. However, the specification provides means for synchronous communication only and leaves out asynchronous communication. As an attempt to fill a gap in this field, we propose, implement and evaluate an approach for the integration of asynchronous messaging into OSGi.

Summary Metagenomic studies use high-throughput sequence data to investigate microbial communities in situ. However, considerable challenges remain in the analysis of these data, particularly with regard to speed and reliable analysis of microbial species as opposed to higher level taxa such as phyla. We here present Genometa, a computationally undemanding graphical user interface program that enables identification of bacterial species and gene content from datasets generated by inexpensive high-throughput short read sequencing technologies. Our approach was first verified on two simulated metagenomic short read datasets, detecting 100% and 94% of the bacterial species included with few false positives or false negatives. Subsequent comparative benchmarking analysis against three popular metagenomic algorithms on an Illumina human gut dataset revealed Genometa to attribute the most reads to bacteria at species level (i.e. including all strains of that species) and demonstrate similar or better accuracy than the other programs. Lastly, speed was demonstrated to be many times that of BLAST due to the use of modern short read aligners. Our method is highly accurate if bacteria in the sample are represented by genomes in the reference sequence but cannot find species absent from the reference. This method is one of the most user-friendly and resource efficient approaches and is thus feasible for rapidly analysing millions of short reads on a personal computer. Availability The Genometa program, a step by step tutorial and Java source code are freely available from http://genomics1.mh-hannover.de/genometa/ and on http://code.google.com/p/genometa/. This program has been tested on Ubuntu Linux and Windows XP/7.

We use linear stochastic Langevin equations to describe the Lyapunov exponents in coupled chaotic systems. The largest Lyapunov exponent is calculated analytically, using the stationary solution of the Fokker-Planck equation. For small couplings we reproduce the singularity which was first described by Daido as the effect of coupling sensitivity of chaos. The singularity is shown to depend on the coupling and the systems’ mismatch. The analytical results are confirmed by numerical simulations.

We study two coupled spatially extended dynamical systems which exhibit space-time chaos. The transition to the synchronized state is treated as a nonequilibrium phase transition, where the average synchronization error is the order parameter. The transition in one-dimensional systems is found to be generically in the universality class of the Kardar- Parisi-Zhang equation with a growth-limiting term ("bounded KPZ"). For systems with very strong nonlinearities in the local dynamics, however, the transition is found to be in the universality class of directed percolation.

The effect of coupling sensitivity of chaos is known as logarithmic singular behavior of the Lyapunov exponents of coupled chaotic systems at small values of the coupling parameter. In order to study it analytically, we use a continuous-time stochastic model which can be treated by means of the Fokker-Planck equation. One main result is that the singularity depends on the fluctuations of the finite-time Lyapunov exponents and on the mismatch between the coupled systems. We derive scaling relations for the Lyapunov exponents and give a qualitative explanation of the origin of the logarithmic singularity. The analytical predictions are compared with results of numerical calculations for different deterministic systems.

We develop a statistical theory of the coupling sensitivity of chaos. The effect was first described by Daido [Prog. Theor. Phys. 72, 853 (1984)]; it appears as a logarithmic singularity in the Lyapunov exponent in coupled chaotic systems at very small couplings. Using a continuous-time stochastic model for the coupled systems we derive a scaling relation for the largest Lyapunov exponent. The singularity is shown to depend on the coupling and the systems' mismatch. Generalizations to the cases of asymmetrical coupling and three interacting oscillators are considered, too. The analytical results are confirmed by numerical simulations.

The behavior of the Lyapunov exponents (LEs) of a disordered system consisting of mutually coupled chaotic maps with different parameters is studied. The LEs are demonstrated to exhibit avoided crossing and level repulsion, qualitatively similar to the behavior of energy levels in quantum chaos. Recent results for the coupling dependence of the LEs of two coupled chaotic systems are used to explain the phenomenon and to derive an approximate expression for the distribution functions of LE spacings. The depletion of the level spacing distribution is shown to be exponentially strong at small values. The results are interpreted in terms of the random matrix theory.

A simple one-dimensional microscopic model of the depinning transition of an interface from an attractive hard wall is introduced and investigated. Upon varying a control parameter, the critical behaviour observed along the transition line changes from a directed-percolation to a multiplicative-noise type. Numerical simulations allow for a quantitative study of the multicritical point separating the two regions, Mean-field arguments and the mapping on a yet simpler model provide some further insight on the overall scenario., 4 pages, 3 figures

Two unidirectionally coupled external cavity semiconductor lasers showing chaotic intensity fluctuations are studied by numerically solving the Lang-Kobayashi model equations [IEEE J. Quantum Electron. QE-16, 347 (1980)]. The systems are shown to synchronize when operating in the regime of low-frequency fluctuations, which is characterized by a very high-dimensional $(dg150)$ attractor. The influence of parameter differences between the two lasers on the synchronization quality is investigated.