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MonteVideo Soundscapes
(2016)
Wireless Sensor Networks (WSN) have emerged as interesting topic in the research community due to its manifold applications. One of the main challenges of this field is the energy consumption of the nodes, which typically is quite restricted due to the required lifetime of such WSNs. To solve that problem several energy-saving MAC protocols have been developed so far. One of them recently presented by the authors is the so-called SmartMAC as an extension to the IEEE802.15.4 standard. In this paper, we present the implementation details of the porting of the SmartMAC protocol to the discrete event network simulator NS3. We develop this module for NS3 to simulate the performance, multi node execution, and multi node configuration. Along with this model, we also present an energy model for the evaluation of the energy consumption. The current implementation in NS3 is based on the LR-WPAN (Low-Rate Wireless Personal Area Networks) as specified by the IEEE802.15.4 (2006) standard. The simulation results show that the SmartMAC with its sleep and wake-up mechanisms for the transceivers, is significantly more efficient than the current NS3 MAC (Medium Access Control) scheme.
The paper conceptualizes the systemic approach for enhancing innovative and competitive capacity of industrial companies (named as Advanced Innovation Design Approach – AIDA) including analysis, optimizations and further development of the innovation process and promoting the innovation climate in industrial companies. The innovation process is understood as a holistic stage-gate system comprising following typical phases with feedback loops and simultaneous auxiliary or follow-up processes: uncovering of solution-neutral customer needs, technology and market trends, identification of the needs and problems with high market potential and formulation of the innovation tasks and strategy, idea generation and problem solving, evaluation and enhancement of solution ideas, creation of innovation concepts based on solution ideas, evaluation of the innovation concepts as well as implementation, validation and market launch of chosen innovation concepts. The article presents the current state of innovation research and discusses the actual status of innovation process in the industrial environment. It defines the future research tasks for amplification of the innovation process with self-configuration, self-optimization, self-diagnostics and intelligent information processing and communication.
Die neueste Generation von programmierbaren Logikbausteinen verfügt neben den konfigurierbaren Logikzellen über einen oder mehrere leistungsfähige Mikroprozessoren. In dieser Arbeit wird gezeigt, wie ein bestehendes Zwei-Chip-System auf einen Xilinx Zynq 7000 mit zwei ARM A9-Cores migriert wird. Bei dem System handelt es sich um das „GPS-gestützte Kreisel-system ADMA“ des Unternehmens GeneSys. Die neue Lösung verbessert den Datenaustausch zwischen dem ersten Mikroprozessor zur digitalen Signalverarbeitung und dem zweiten Prozessor zur Ablaufsteuerung durch ein Shared Memory. Für die schnelle und echtzeitfähige Datenübertragung werden zahlreiche hochbitratige Schnittstellengenutzt.
The aim of this data collection is to enforce evidence of SCS effectiveness in treating neuropathic chronic pain and the very low percentage of undesired side effects of complications reported in our case series suggests that all implants should be performed by similarly well-trained and experienced professionals.
The M-Bus protocol (EN13757) is in widespread use for metering applications within home area and neighborhood area networks, but lacks a strict specification. This may lead to incompatibilities in real-life installations and to problems in the deployment of new M-Bus networks. This paper presents the development of a novel testbed to emulate physical Metering Bus (M-Bus) networks with different topologies and to allow the flexible verification of real M-Bus devices in real-world scenarios. The testbed is designed to support device manufacturers and service technicians in test and analysis of their devices within a specific network before their installation. The testbed is fully programmable, allowing flexible changes of network topologies, cable lengths and types. Itis easy to use, as only the master and the slaves devices have to be physically connected. This allows to autonomously perform multiple tests, including automated regression tests. The testbed is available to other researchers and developers. We invite companies and research institutions to use this M-Bus testbed to increase the common knowledge and real-world experience.
Phenolic compounds, such as flavonoids and phenolic acids, are very important substances that occur in various medicinal plants. They show different pharmacological activities which might be useful in the therapy of many diseases. Phenolic compounds have achieved an increasing interest over the last years because these compounds are easily oxidized and, thus, act as strong antioxidants. We present the chemiluminescence of different phenolic compounds measured directly on high-performance thin-layer chromatography LiChrospher® plates using the oxalic acid derivative bis(2,4,6-trichlorophenyl) oxalate (TCPO) in conjunction with H2O2. Our results indicate that chemiluminescence intensity increases with an ascending number of phenolic groups in the molecule. The method can be used to detect phenolic compounds in beverages like coffee, tea, and wine.
The number of impaired persons rises -- as a result of both regular degradation with age and psychological problems like burnout. Sheltered work organizations aim to reintegrate impaired persons into work environments and prepare them for the re-entry in the regular job market.
Both for elderly and for impaired persons it is crucial to quickly assess the abilities, to identify limits and potentials and thus find work processes suitable for their skill profile.
This work focuses on the analysis and comparison of software-tools that assess the abilities of persons with impairments. We describe two established generic tools (CANTAB, Cogstate), analyze a yet unknown specialized tool (Hamet) and present a new gamified tool (GATRAS).
Finally, we present a study with 20 participants with impairments, comparing the tools against a ground truth baseline generated by a real-world assembly task.
Drehzahlzustandsregelung
(2016)
In this work, we consider a duty-cycled wireless sensor network with the assumption that the on/off schedules are uncoordinated. In such networks, as all nodes may not be awake during the transmission of time synchronization messages, nodes will require to re-transmit the synchronization messages. Ideally a node should re-transmit for the maximum sleep duration to ensure that all nodes are synchronized. However, such a proposition will immensely increase the energy consumption of the nodes. Such a situation demands that there is an upper bound of the number of retransmissions. We refer to the time a node spends in re-transmission of the control message as broadcast duration. We ask the question, what should be the broadcast duration to ensure that a certain percentage of the available nodes are synchronized. The problem to estimate the broadcast duration is formulated so as to capture the probability threshold of the nodes being synchronized. Results show the proposed analytical model can predict the broadcast duration with a given lower error margin under real world conditions, thus demonstrating the efficiency of our solution.
IPv6 over resource-constrained devices (6Lo) emerged as a de-facto standard for the Internet of Things (IoT) applications especially in home and building automation systems. We provide results of an investigation of the applicability of 6LoWPAN with RPL mesh networks for home and building automation use cases. The proper selection of Trickle parameters and neighbor reachable time-outs is important in the RPL protocol suite to respond efficiently to any path failure. These parameters were analyzed in the context of energy consumption w.r.t the number of control packets. The measurements were performed in an Automated Physical Testbeds (APTB). The results match the recommendation by RFC 7733 for selecting various parameters of RPL protocol suite. This paper shows the relationship between various RPL parameters and control traffic overhead during network rebuild. Comparative measurement results with Bluetooth Low Energy (BLE) in this work showed that 6Lo with RPL outperformed BLE in this use case with less control traffic overheads.
Electric arc furnaces (EAF) are complex industrial plants whose actual behavior depends upon numerous factors. Due to its energy intensive operation, the EAF process has always been subject to optimization efforts. For these reasons, several models have been proposed in literature to analyze and predict different modes of operation. Most of these models focused on the processes inside the vessel itself. The present paper introduces a dynamic, physics-based model of a complete EAF plant which consists of the four subsystems vessel, electric system, electrode regulation, and off-gas system. Furthermore the solid phase is not treated to be homogenous but a simple spatial discretization is employed. Hence it is possible to simulate the energy input by electric arcs and fossil fuel burners depending on the state of the melting progress. The model is implemented in object-oriented, equation-based language Modelica. The simulation results are compared to literature data.
We present a videodensitometric quantification method for methadone in syrup, separated by thin-layer chromatography (TLC). The quantification is based on a derivation reaction with Dragendorf reagent. Measurements were carried out using a 16-bit flatbed scanner. The range of linearity covers two magnitudes of power using the Kubelka-Munk expression for data transformation. The separation method is inexpensive, fast, and reliable.
In the last decade, IPv6 over Low power Wireless Personal Area Networks (IEEE802.15.4), also known as 6LoWPAN, has well evolved as a primary contender for short range wireless communications and holds the promise of an Internet of Things, which is completely based on the Internet Protocol. The authors' team has developed a 6LoWPAN protocol stack in C language, the stack without the necessity to use a specific design environment or operating system. It is highly flexible, modular, and portable and can be enhanced by several interesting modules, like a Wake-On-Radio-(WOR) MAC layer or a TLS1.2 based security sublayer. The stack is made available as open source at https://github.com/hso-esk/emb6. It was extensively tested on the Automated Physical Testbed (APTB) for Wireless Systems, which is available in the authors' lab and allows a flexible setup and full control of arbitrary topologies. The results of the measurements demonstrate a very good stability and short-term with long-term performance also under dynamic conditions.
Wireless communication systems more and more become part of our daily live. Especially with the Internet of Things (IoT) the overall connectivity increases rapidly since everyday objects become part of the global network. For this purpose several new wireless protocols have arisen, whereas 6LoWPAN (IPv6 over Low power Wireless Personal Area Networks) can be seen as one of the most important protocols within this sector. Originally designed on top of the IEEE802.15.4 standard it is a subject to various adaptions that will allow to use 6LoWPAN over different technologies; e.g. DECT Ultra Low Energy (ULE). Although this high connectivity offers a lot of new possibilities, there are several requirements and pitfalls coming along with such new systems. With an increasing number of connected devices the interoperability between different providers is one of the biggest challenges, which makes it necessary to verify the functionality and stability of the devices and the network. Therefore testing becomes one of the key components that decides on success or failure of such a system. Although there are several protocol implementations commonly available; e.g., for IoT based systems, there is still a lack of according tools and environments as well as for functional and conformance testing. This article describes the architecture and functioning of the proposed test framework based on Testing and Test Control Notation Version 3 (TTCN-3) for 6LoWPAN over ULE networks.
There is a growing trend for the use of thermo-active building systems (TABS) for the heating and cooling of buildings, because these systems are known to be very economical and efficient. However, their control is complicated due to the large thermal inertia, and their parameterization is time-consuming. With conventional TABS-control strategies, the required thermal comfort in buildings can often not be maintained, particularly if the internal heat sources are suddenly changed. This paper shows measurement results and evaluations of the operation of a novel adaptive and predictive calculation method, based on a multiple linear regression (AMLR) for the control of TABS. The measurement results are compared with the standard TABS strategy. The results show that the electrical pump energy could be reduced by more than 86%. Including the weather adjustment, it could be demonstrated that thermal energy savings of over 41% could be reached. In addition, the thermal comfort could be improved due to the possibility to specify mean room set-point temperatures. With the AMLR, comfort category I of the comfort norms ISO 7730 and DIN EN 15251 are observed in about 95% of occasions. With the standard TABS strategy, only about 24% are within category I.
Adaptive predictive control of thermo-active building systems (TABS) based on a multiple regression algorithm: First practical test. Available from: https://www.researchgate.net/publication/305903009_Adaptive_predictive_control_of_thermo-active_building_systems_TABS_based_on_a_multiple_regression_algorithm_First_practical_test [accessed Jul 7, 2017].
The famous violin virtuoso Nicolò Paganini (born on 27 October 1782 in Genoa, died on 27 May 1840 in Nice) left us with many puzzles. An interesting aspect is his hair: In the 19th century, hair given away as a token of friendship or romantic love became very popular, and Paganini also seems to have made use of this fad. In 2009, a lock of hair, purportedly that of Paganini, kept in a locked presentation box together with a bilingual autograph inscription saying: "Alla Signora Chatterton avec les compliments de Nicolò Paganini" was bought at an auction. From this hair lock a sample was taken and was investigated morphologically by using digital light microscopy (digital microscope VHX-100, Keyence) in reflected and transmitted light with and without polarization at different magnifications up to 1:5,000. The sample was then compared with a hair sample from the possession of the Paganini family, which had been microscopically examined in 2012 by the co-author of this paper yielding numerous figures with measurement results that had been stored and could be retrieved for direct comparison. The hair sample consisted of ten strands of hair or hair fragments and was investigated with great effort for the following parameters: exogenous hair damage, especially feeding traces caused by parasites, modeling and angulation of hairs, hair thickness, medulla and pigmentation, curling and mercury load on the trace material. After evaluation of all findings not only a non-exclusion of identity can be determined, but due to the broad match of also rare findings there is no reasonable doubt about their identity. In addition, the findings suggest that the studied hair samples are in fact from Paganini's head. The present case of Nicolò Paganini's hair lock is also an excellent starting point for reflections on the probative value of trace hair investigations. This point is also critically discussed in the paper. Finally, this study shows that said lock of hair had probably really been dedicated and given to Eliza Davenport Latham (born on 25 November 1806, died on 9 January 1877), the future wife of the, at that time, best-known and most famous English harpist John Balsir Chatterton (born on 25 November 1804, died on 9 April 1871). Paganini must have met her on his concert tour 1831/32, where he had travelled to Paris, London, the rest of England, Scotland and Ireland.
All you need is sleep
(2016)
In 21st century, the century when the humanity hopes to embark on interplanetary travel, we are yet to fully reach an understanding of our very own idiosyncratic terra incognita – the human sleep. Sleep is a highly conserved evolutionary process that constitutes approximately one third of our life, and the lack or inadequate sleep may lead to impairment across multiple cognitive domains (Tononi and Cirelli, 2014; Lim and Dinges, 2010). Sleep deprivation also leads to aberrant brain functioning, immunological and metabolic collapse, and if it is sufficiently prolonged it will ultimately lead to death (Tononi and Cirelli, 2014).
There is increasing evidence of central hyperexcitability in chronic whiplash-associated disorders (cWAD). However, little is known about how an apparently simple cervical spine injury can induce changes in cerebral processes. The present study was designed (1) to validate previous results showing alterations of regional cerebral blood flow (rCBF) in cWAD, (2) to test if central hyperexcitability reflects changes in rCBF upon non-painful stimulation of the neck, and (3) to verify our hypothesis that the missing link in understanding the underlying pathophysiology could be the close interaction between the neck and midbrain structures. For this purpose, alterations of rCBF were explored in a case-control study using H215O positron emission tomography, where each group was exposed to four different conditions, including rest and different levels of non-painful electrical stimulation of the neck. rCBF was found to be elevated in patients with cWAD in the posterior cingulate and precuneus, and decreased in the superior temporal, parahippocampal, and inferior frontal gyri, the thalamus and the insular cortex when compared with rCBF in healthy controls. No differences in rCBF were observed between different levels of electrical stimulation. The alterations in regions directly involved with pain perception and interoceptive processing indicate that cWAD symptoms might be the consequence of a mismatch during the integration of information in brain regions involved in pain processing.
A Survey of Channel Measurements and Models for Current and Future Railway Communication Systems
(2016)
The humanoid Sweaty was the finalist in this year’s robocup soccer championship(adult size). For the optimization of the gait and the stability, data concerning forces and torques in the ankle joints would be helpful. In the following paper the development of a six-axis force and torque sensor for the humanoid robot Sweaty is described. Since commercial sensors do not meet the demands for the sensors in Sweatys ankle joints, a new sensor was developed. As a measuring devices we used strain gauges and custom electronics based on an acam PS09. The geometry was analyzed with the FEM program ANSYS to get optimal dimensions for the measuring beams. In addition ANSYS was used to optimize the position for the strain gauges on the beam.
Due to its numerous application fields and benefits, virtualization has become an interesting and attractive topic in computer and mobile systems, as it promises advantages for security and cost efficiency. However, it may bring additional performance overhead. Recently, CPU virtualization has become more popular for embedded platforms, where the performance overhead is especially critical. In this article, we present the measurements of the performance overhead of the two hypervisors Xen and Jailhouse on ARM processors in the context of the heavy load “Cpuburn-a8” application and compare it to a native Linux system running on ARM processors.
Remote code attestation protocols are an essential building block to offer a reasonable system security for wireless embedded devices. In the work at hand we investigate in detail the trustability of a purely software-based remote code attestation based inference mechanism over the wireless when e.g. running the prominent protocol derivate SoftWare-based ATTestation for Embedded Devices (SWATT). Besides the disclosure of pitfalls of such a protocol class we also point out good parameter choices which allow at least a meaningful plausibility check with a balanced false positive and false negative ratio.
Proton Exchange Membrane Fuel Cells (PEMFC) are energy efficient and environmentally friendly alternatives to conventional energy conversion systems in many yet emerging applications. In order to enable prediction of their performance and durability, it is crucial to gain a deeper understanding of the relevant operation phenomena, e.g., electrochemistry, transport phenomena, thermodynamics as well as the mechanisms leading to the degradation of cell components. Achieving the goal of providing predictive tools to model PEMFC performance, durability and degradation is a challenging task requiring the development of detailed and realistic models reaching from the atomic/molecular scale over the meso scale of structures and materials up to components, stack and system level. In addition an appropriate way of coupling the different scales is required.
This review provides a comprehensive overview of the state of the art in modeling of PEMFC, covering all relevant scales from atomistic up to system level as well as the coupling between these scales. Furthermore, it focuses on the modeling of PEMFC degradation mechanisms and on the coupling between performance and degradation models.
This paper focuses on appropriately measuring the accuracy of forecasts of load behavior and renewable generation in micro-grid operation. Common accuracy measures like the root mean square of the error are often difficult to interpret for system design, as they describe the mean accuracy of the forecast. Micro-grid systems, however, have to be designed to handle also worst case situations. This paper therefore suggests two error measures that are based on the maximum function and that better allow understanding worst case requirements with respect to balancing power and balancing energy supply.
BACKGROUND:
While hearing aids for a contralateral routing of signals (CROS-HA) and bone conduction devices have been the traditional treatment for single-sided deafness (SSD) and asymmetric hearing loss (AHL), in recent years, cochlear implants (CIs) have increasingly become a viable treatment choice, particularly in countries where regulatory approval and reimbursement schemes are in place. Part of the reason for this shift is that the CI is the only device capable of restoring bilateral input to the auditory system and hence of possibly reinstating binaural hearing. Although several studies have independently shown that the CI is a safe and effective treatment for SSD and AHL, clinical outcome measures in those studies and across CI centers vary greatly. Only with a consistent use of defined and agreed-upon outcome measures across centers can high-level evidence be generated to assess the safety and efficacy of CIs and alternative treatments in recipients with SSD and AHL.
METHODS:
This paper presents a comparative study design and minimum outcome measures for the assessment of current treatment options in patients with SSD/AHL. The protocol was developed, discussed, and eventually agreed upon by expert panels that convened at the 2015 APSCI conference in Beijing, China, and at the CI 2016 conference in Toronto, Canada.
RESULTS:
A longitudinal study design comparing CROS-HA, BCD, and CI treatments is proposed. The recommended outcome measures include (1) speech in noise testing, using the same set of 3 spatial configurations to compare binaural benefits such as summation, squelch, and head shadow across devices; (2) localization testing, using stimuli that rove in both level and spectral content; (3) questionnaires to collect quality of life measures and the frequency of device use; and (4) questionnaires for assessing the impact of tinnitus before and after treatment, if applicable.
CONCLUSION:
A protocol for the assessment of treatment options and outcomes in recipients with SSD and AHL is presented. The proposed set of minimum outcome measures aims at harmonizing assessment methods across centers and thus at generating a growing body of high-level evidence for those treatment options.
Der Kaiser ist ja nackt
(2016)
Die Verdinglichung des Menschen: Mit Gesundheitskarte, Selftracking und E-Health zum homo digitalis
(2016)
In recent years simple CAD systems have entered the market, which are offered as freeware or open source projects. These systems prove to be a key technology especially for the further expansion of 3D printing, because a 3D model of the object to be printed is a prerequisite for the use of a 3D printer. Therefore, this contribution reviews several common simple CAD systems. Thus technical and economic criteria are evaluated. It is also demonstrated how the models designed in this manner can be used in 3D printing. A case study shows the possibilities and limitations to be expected when using simple CAD systems.
Electrochemical impedance spectroscopy (EIS) is a widely-used diagnostic technique to characterize electrochemical processes. It is based on the dynamic analysis of two electrical observables, that is, current and voltage. Electrochemical cells with gaseous reactants or products (e.g., fuel cells, metal/air cells, electrolyzers) offer an additional observable, that is, the gas pressure. The dynamic coupling of current and/or voltage with gas pressure gives rise to a number of additional impedance definitions, for which we use the term electrochemical pressure impedance. It also gives rise to different experimental probing approaches. In this article we present a model-based study of electrochemical pressure impedance spectroscopy (EPIS). Possible quantifications and realizations of EPIS are discussed. The study of generic cell geometries consisting of gas reservoir, diffusion layer(s) and electrochemically active layer(s) reveals distinct spiral-shaped features in the Nyquist plot. Using the example of a sodium/oxygen (Na/O2) cell, the dynamic spatiotemporal behavior of the state variables is quantified and interpreted. Results are compared to first experimental EPIS measurements by Hartmann et al. [J. Phys. Chem. C118, 1461, 2014]. A sensitivity analysis highlights the properties of EPIS with respect to geometric, transport, and kinetic parameters. We demonstrate that EPIS is sensitive to transport parameters that are not well-accessible with standard EIS.
Lithium–oxygen cells with nonaqueous electrolyte show high overpotentials during charge, indicating asymmetric charge/discharge reaction mechanisms. We present a kinetic modeling and simulation study of the lithium–oxygen cell cycling behavior. The model includes a multistep reaction mechanism of the cell reaction (2Li + O2 ⇄ Li2O2) forming lithium peroxide by precipitation, coupled to a 1D porous-electrode transport model. We apply the model to study the asymmetric discharge/charge characteristics and analyze the influence of a redox mediator dissolved homogeneously in the liquid electrolyte. Model predictions are compared to experimental galvanostatic cycling data of cells without and with 2,2,6,6-tetramethylpiperidinyloxyl (TEMPO) as redox mediator. The predicted discharge behavior shows good agreement with the experimental results. A spatiotemporal analysis of species concentrations reveals inhomogeneous distributions of dissolved oxygen and reaction products within the cathode during discharge. The experimentally observed charge overpotentials as well as their reduction by using a redox mediator can be qualitatively reproduced with a partially irreversible reaction mechanism. However, the proposed models fail to reproduce the particular shape of the experimental charge curve with continuously increasing charge overpotential, which implies that part of the reaction mechanism is still open for investigation in future work.