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A fast transient current-mode buckboost DC-DC converter for portable devices is presented. Running at 1 MHz the converter provides stable 3 V from a 2.7 V to 4.2 V Li-Ion battery. A small voltage under-/overshoot is achieved by fast transient techniques: (1) adaptive pulse skipping (APS) and (2) adaptive compensation capacitance (ACC). The proposed converter was implemented in a 0.25 μm CMOS technology. Load transient simulations confirm the effectiveness of APS and ACC. The improvement in voltage undershoot and response time at light-to-heavy load step (100 mA to 500 mA), are 17 % and 59 %, respectively, in boost mode and 40 % and 49 %, respectively, in buck mode. Similar results are achieved at heavy-to-light load step for overshoot and response time.
Energy-efficiency and safety became an important factor for car manufacturers. Thus, the cars have been optimised regarding the energy consumption and safety by optimising for example the power train or the engine. Besides the optimisation of the car itself, energy-efficiency and safety can also be increased by adapting the individual driving behaviour to the current driving situation. This paper introduces a driving system, which is in development. Its goal is to optimise the driving behaviour in terms of energy-efficiency and safety by giving recommendations to the driver. For the creation of a recommendation the driving system monitors the driver and the current driving situation as well as the car using in-vehicle sensors and serial-bus systems. On the basis of the acquired data, the driving system will give individual energy-efficiency and safety recommendations in real-time. This will allow eliminating bad driving habits, while considering the driver needs.
The Fifth International Conference on Advances in Databases, Knowledge, and Data Applications [DBKDA 2013], held between January 27th- February 1st, 2013 in Seville, Spain, continued a series of international events covering a large spectrum of topics related to advances in fundamentals on databases, evolution of relation between databases and other domains, data base technologies and content processing, as well as specifics in applications domains databases. Advances in different technologies and domains related to databases triggered substantial improvements for content processing, information indexing, and data, process and knowledge mining. The push came from Web services, artificial intelligence, and agent technologies, as well as from the generalization of the XML adoption. High-speed communications and computations, large storage capacities, and loadbalancing for distributed databases access allow new approaches for content processing with incomplete patterns, advanced ranking algorithms and advanced indexing methods. Evolution on e-business, ehealth and telemedicine, bioinformatics, finance and marketing, geographical positioning systems put pressure on database communities to push the ‘de facto’ methods to support new requirements in terms of scalability, privacy, performance, indexing, and heterogeneity of both content and technology. We take here the opportunity to warmly thank all the members of the DBKDA 2013 Technical Program Committee, as well as the numerous reviewers. The creation of such a high quality conference program would not have been possible without their involvement. We also kindly thank all the authors who dedicated much of their time and efforts to contribute to DBKDA 2013. We truly believe that, thanks to all these efforts, the final conference program consisted of top quality contributions. Also, this event could not have been a reality without the support of many individuals, organizations, and sponsors. We are grateful to the members of the DBKDA 2013 organizing committee for their help in handling the logistics and for their work to make this professional meeting a success. We hope that DBKDA 2013 was a successful international forum for the exchange of ideas and results between academia and industry and for the promotion of progress in the fields of databases, knowledge and data applications. We are convinced that the participants found the event useful and communications very open. We also hope the attendees enjoyed the charm of Seville, Spain.
The workshop aims to discuss leading edge contributions to the interdisciplinary research area of ambient intelligence (AmI) applied to the domains of telemedicine and driving assistance. AmI refers to human centered environments attributed with sensors. The development of AmI in the two application domains of the workshop shares several commonalities: the extensive usage of networked devices and sensors, the design of artificial intelligence algorithms for diagnosis, including recommendation systems and qualitative reasoning or the application of mobile and wireless communication to their distributed systems. Together with the presentation of common aspects of Ambient Intelligence, a further goal of the workshop is to stimulate synergies among both application domains and present examples. The telemedicine domain can benefit from methodologies in designing complex devices, real-time conform system design, audiovisual or computer vision system design used in automotive driving assistance. Furthermore, the automotive domain can benefit from the usercentric view, biometric sensor data design, multi-user data bases for aggregation and diagnosis using big data like used in telemedicine. The German Government supports these research lines in its Hightec-Strategie under the domains “Health and Nutrition” and “Climate and Energy”. In Spain the term “Spanish Program for R&D Challenged Oriented Society – Challenge in energy safe, efficient and clean & Challenge in sustainable transport, smart and integrated” is used. Scientific contributions to the event are peer-reviewed by a suited program committee having members from Germany and Spain. The same committee is serving the JARCA workshop (Jornadas sobre Sistemas cualitativos y sus Aplicaciones en Diagnosis, Robótica e Inteligencia Ambiental - Conference on Qualitative Systems and their Applications in Diagnoses, Robotics and Ambient Intelligence) since 15 years. This workshop is sponsored by the German Academic Exchange Service (DAAD) under contract number 57070010.
When forecasting sales figures, not only the sales history but also the future price of a product will influence the sales quantity. At first sight, multivariate time series seem to be the appropriate model for this task. Nontheless, in real life history is not always repeatable, i.e. in the case of sales history there is only one price for a product at a given time. This complicates the design of a multivariate time series. However, for some seasonal or perishable products the price is rather a function of the expiration date than of the sales history. This additional information can help to design a more accurate and causal time series model. The proposed solution uses an univariate time series model but takes the price of a product as a parameter that influences systematically the prediction. The price influence is computed based on historical sales data using correlation analysis and adjustable price ranges to identify products with comparable history. Compared to other techniques this novel approach is easy to compute and allows to preset the price parameter for predictions and simulations. Tests with data from the Data Mining Cup 2012 demonstrate better results than established sophisticated time series methods.
Die Wahl einer Klinik ist typischerweise dem stellvertretenden Kaufverhalten zuzuordnen – Kunden suchen vertrauenswürdige, persönliche Quellen zur Unterstützung der Entscheidung. Weiterempfehlungsverhalten kann durch Anreize unterstützt werden – grundlegende Voraussetzung für ehrliche Weiterempfehlung ist jedoch Kundenzufriedenheit. Kundenzufriedenheit entsteht durch den Abgleich zwischen erwarteter und empfundener Leistung – das erwartete Leistungsniveau wird häufig durch Unternehmen anderer Branchen determiniert. Individuen sind nicht in der Lage, die Bestandteile einer Erfahrung isoliert zu bewerten, sondern vermengen sie (Halo-Effekt) - Inkonsistenzen führen zu einer Abwertung der Gesamterfahrung. Darum ist im ersten Schritt die Identifikation der Gesamterfahrung (Kundenreise) erforderlich – diese beginnt vor und endet nach der unmittelbaren Interaktion des Kunden mit dem Unternehmen / der Klinik. Im zweiten Schritt sind die Zufriedenheitstreiber und die Interdependenzen zwischen den Einzelerfahrungen zu ermitteln um dann die Optimierung der Kundenreise zu planen und umzusetzen.
Proceedings of the International Workshop on Mobile Networks for Biometric Data Analysis (mBiDA)
(2014)
Prevention and treatment of common and widesprea (chronic) diseases is a challenge in any modern Society and vitally important for health maintenance in aging societies. Capturing biometric data is a cornerstone for any analysis and Treatment strategy. Latest advances in sensor technology allow accurate data measurement in a non-intrusive way. In many cases, it is necessary to provide online monitoring and real-time data capturing to support patients´ prevention plans or to allow medical professionals to access the current status. Different communication standards are required to push sensor data and to store and analyze them on different (mobile) platforms. The objective of the workshop is to show new and innovative approaches dedicated to biometric data capture and analysis in a non-intrusive way maintaining mobility. Examples can be found in human centered ambient intelligence attributed with sensors or even in methodologies applied in automotive real-time conform mobile system design. The workshop´s main challenge is to focus on approaches promoting non-intrusiveness, reliable prediction algorithms and high user-acceptance. The workshop will provide overview presentations, Young researcher poster tracks, doctoral tracks and classical peer-review full paper tracks. Especially, would like to encourage students and young researchers to participate and to contribute to the workshop. Scientific contributions to the event are peer-reviewed by a suited program committee.
The impact of stress of every human being has become a serious problem. Reported impact on persons are a higher rate or health disorders like heart problems, obesity, asthma, diabetes, depressions and many others. An individual in a stressful situation has to deal with altered cognition as well as an affected decision making skill and problem solving. This could lead to a higher risk for accidents in dynamic environments such as automotive. Different papers faced the estimation as well as prediction of drivers’ stress level during driving. Another important question is not only the stress level of the driver himself, but also the influence on and of a group of other drivers in the near area. This paper proposes a system, which determines a group of drivers in a near area as clusters and it derives or computes the individual stress level. This information will be analyzed to generate a stress map, which represents a graphical view about road section with a higher stress influence. Aggregated data can be used to generate navigation routes with a lower stress influence as well as recommend driving behavior to decrease stress influenced driving as well as improve road safety.
In this paper, research projects with 30 meter balanced cabling and data rates up to 25 Gbps over one single pair are described. The project aim is to achieve 100 Gbps via a four pair balanced cabling channel. In the following, spectral characteristics of the used prototype twisted pair are presented. Therefore, the insertion loss of the single cable in comparison to the insertion loss of the cable in combination with an equalizing amplifier, as well as the group delay of the cable and the cable connected to the equalizing amplifier is shown. Furthermore, a carrierless Pulse Amplitude Modulation with 32 different levels (PAM-32) as an approach for a possible line encoding is presented. Finally, research measurements of the data transmission with a data rate up to 25 Gbps via shielded twisted pair is shown.
An index in a Multi-Version DBMS (MV-DBMS) has to reflect different tuple versions of a single data item. Existing approaches follow the paradigm of logically separating the tuple version data from the data item, e.g. an index is only allowed to return at most one version of a single data item (while it may return multiple data items that match a search criteria). Hence to determine the valid (and therefore visible) tuple version of a data item, the MV-DBMS first fetches all tuple versions that match the search criteria and subsequently filters visible versions using visibility checks. This involves I/O storage accesses to tuple versions that do not have to be fetched. In this vision paper we present the Multi Version Index (MV-IDX) approach that allows index-only visibility checks which significantly reduce the amount of I/O storage accesses as well as the index maintenance overhead. The MV-IDX achieves significantly lower response times and higher transactional throughput on OLTP workloads.
IGBT modules with anti-parallel FWDs are widely used in inductive load switching power applications, such as motor drive applications. Nowadays there is a continuous effort to increase the efficiency of such systems by decreasing their switching losses. This paper addresses the problems arising in the turn-on process of an IGBT working in hard-switching conditions. A method is proposed which achieves – contrary to most other approaches – a high switching speed and, at the same time, a low peak reverse-recovery current. This is done by applying an improved gate current waveform that is briefly lowered during the turn-on process. The proposed method achieves low switching losses. Its effectiveness is demonstrated by experimental results with IGBT modules for 600V and 1200V.
Advanced power semiconductors such as DMOS transistors are key components of modern power electronic systems. Recent discrete and integrated DMOS technologies have very low area-specific on-state resistances so that devices with small sizes can be chosen. However, their power dissipation can sometimes be large, for example in fault conditions, causing the device temperature to rise significantly. This can lead to excessive temperatures, reduced lifetime, and possibly even thermal runaway and subsequent destruction. Therefore, it is required to ensure already in the design phase that the temperature always remains in an acceptable range. This paper will show how self-heating in DMOS transistors can be experimentally determined with high accuracy. Further, it will be discussed how numerical electrothermal simulations can be carried out efficiently, allowing the accurate assessment of self-heating within a few minutes. The presented approach has been successfully verified experimentally for device temperatures exceeding 500 ◦C up to the onset of thermal runaway.
This paper presents a new broadband antenna for satellite communications. It describes the procedure involved in the design of a microstrip antenna array and its multi-level passive feed network that together yield circular polarization and the necessary gain to be used in an earth-satellite link. The designed antenna is notable for its large bandwidth, circular polarization, high gain and small dimensions.
This paper presents the design and simulation processes of an Equiangular Spiral Antenna for the extremely high frequencies between 65 GHz and 170 GHz. A new approach for the analysis of the antenna’s electrical parameters is described. This approach is based on formalism proposed by Rumsey to determine the EM field produced by an equiangular spiral antenna. Analytical expressions of the electrical parameters such as the gain or the directivity are then calculated using well sustained mathematical approximations. The comparison of obtained results with those from numerical integration methods shows a good agreement.
Functionally impaired people have problems with choosing and finding the right clothing. So, they need help in their daily life to wash and manage the clothing. The goal of this work is to support the user by giving recommendations to choose the right clothing, to find the clothing and how to wash the clothing. The idea behind eKlarA is to generate a gateway based system that uses sensors to identify the clothing and their state in the clothing cycle. The clothing cycle consists of (one and more) closet, laundry basket and washing machine in one or several places. The gateway uses the information about the clothing, weather and calendar to support the user in the different steps of the clothing cycle. This allows to give more freedom to the functionally impaired people in their daily life.
Besides the optimisation of the car, energy-efficiency and safety can also be increased by optimising the driving behaviour. Based on this fact, a driving system is in development whose goal is to educate the driver in energy-efficient and safe driving. It monitors the driver, the car and the environment and gives energy-efficiency and safety relevant recommendations. However, the driving system tries not to distract or bother the driver by giving recommendations for example during stressful driving situations or when the driver is not interested in that recommendation. Therefore, the driving system monitors the stress level of the driver as well as the reaction of the driver to a given recommendation and decides whether to give a recommendation or not. This allows to suppress recommendations when needed and, thus, to increase the road safety and the user acceptance of the driving system.
Three different polyols (soluble starch, sucrose, and glycerol) were tested for their potential in the chemical modification of melamine formaldehyde (MF) resins for paper impregnation. MF impregnated papers are widely used as finishing materials for engineered wood. These polyols were selected because the presence of multiple hydroxy groups in the molecules was suspected to facilitate cocondensation with the main MF framework. This should lead to good resin performance. Moreover, they are readily produced from natural feedstock. They are available in large quantities and may serve as economically feasible, environmentally harmless alternative co-monomers suitable to substitute a portion of fossil-based starting material. In the presented work, a number of model resins were synthesized and tested for covalent incorporation of the natural polyol into the MF Framework. Spectroscopic evidence of chemical incorporation of glycerol was found by applying by 1H, 13C, 1H/13C HSQC, 1H/13C HMBC, and 1H DOSY methods. It was furthermore found that covalent incorporation of glycerol in the network took place when glycerol was added at different stages during synthesis. Further, all resins were used to prepare decorative laminates and the performance of the novel resins as surface finishing was evaluated using standard technological tests. The technological performance of the various modified thermosetting resins was assessed by determining flow viscosity, molar mass distribution, the storage stability, and in a second step laminating impregnated paper to particle boards and testing the resulting surfaces according to standardized quality tests. In most cases, the average board surface properties were of acceptable quality. Our findings demonstrate the possibility to replace several percent of the petrol-based product melamine by compounds obtained from renewable resources.
Mass-customization is a megatrend that also affects the wood industry. To obtain individually designed laminates in batch size one efficient printing and processing technologies are required. Digital printing was envisaged as it does not depend on highly costly printing cylinders (as used in rotogravure printing) and allows rapid exchange of the printing designs. In the present work, two wellestablished digital printing approaches, the multi-pass and the single-pass technique, were investigated and evaluated for their applicability in decorating engineered wood and low-pressure melamine films. Three different possibilities of implementing digital printing in the decorative laminates manufacturing process were studied: (1) digital printing on coated chipboard and subsequently applying a lacquered top-coat or melamine overlay (designated as “direct printing”, since the LPM was the printing substrate), (2) digital printing on decorative paper which was subsequently impregnated before hot pressing (designated as “indirect printing, variant A”) and (3) digital printing on decorative paper with subsequent interlamination of the paper between impregnated under- and overlay paper layers during the pressing process (designated as “indirect printing, variant B”). Due to various advantages of the resulting cured melamine resin surfaces including a much better technological performance and flexibility in surface texture design, it was decided to industrially further pursue only the indirect digital printing process comprising interlamination and the direct printing process with a melamine overlay-finishing. Basis for the successful trials on production and laboratory scales were the identification of applicable inks (in terms of compatibility with melamine resin) and of appropriate printing paper quality (in terms of impregnation and imprinting ability). After selection and fine tuning of suitable materials, the next challenge to overcome was the initially insufficient bond strength between impregnated overlay and the ink layers which led to unsatisfactory quality of the print appearance and delamination effects. However, the optimization of the pressing program and the development of a modified impregnation procedure for the underlay and overlay papers allowed the successful implementation of digital printing in the production line of our industrial partner FunderMax.
System- und Schnittstellenbeherrschung, Ideen- und Innovationsmanagement sowie die virtuell integrierte Produkt- und Prozessplanung sind zu entwickelnde Kompetenzen, die der veränderten Rolle des Menschen in der Industrie 4.0 Rechnung tragen. Dezidiert adressiert werden können diese in zukunftsweisend ausgerüsteten Lernfabriken.
Enterprise Architectures (EA) consists of many architecture elements, which stand in manifold relationships to each other. Therefore Architecture Analysis is important and very difficult for stakeholders. Due changing an architecture element has impacts on other elements different stakeholders are involved. In practice EAs are often analyzed using visualizations. This article aims at contributing to the field of visual analytics in EAM by analyzing how state of-the-art software platforms in EAM support stakeholders with respect to providing and visualizing the “right” information for decision-making tasks. We investigate the collaborative decision-making process in an experiment with master students using professional EAM tools by developing a research study and accomplishing them in a master’s level class with students.