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Öko-Audit-Erfahrungen bei Eller Repro+Druck (1995)

Pabst, H. P.

Die Geschäftsleitung und Führungskräfte von Eller Repro+Druck beschlossen im Juli 1994 die Teilnahme am damls noch neuen EU-Öko-Audit. Die Durchführung des Audits ist für 1996 geplant. Zwei Diplomanden der FH Offenburg wurde die Möglichkeit gegeben, als externe Berater für Eller Repro+Druck ihre Diplomarbeit über die Vorbereitung zum Öko-Audit zu schreiben. Der Betrieb (170 Mitarbeiter) verfügt über elektronische Bildverarbeitung auf Scitex- und Mac-Schiene, derzeit noch konventionelle Plattenkopie und -entwicklung, fünf Offsetrotationen sowie Weiterverarbeitung mit Sammelheftern und Falzmaschinen. Der Referent berichtet über die Erfahrungen, die sein Unternehmen bis zum Herbst 1995 mit der Vorbereitung zum Öko-Audit gemacht hat, und gibt Praxistips. Zusammen mit den Beratern wurden eine Aufnahme der betrieblichen Situation durchgeführt, Maßnahmen geplant und zum Teil durchgeführt.

Optical Multiwavelength Technique Applied to the Online Measurement of Particle Emissions from Engines (2001)

Zahoransky, Richard A. ; Saier, T. ; Laile, Edgar ; Nikitidis, Michail S. ; Konstandopoulos, Athanasios G.

The importance of obtaining simultaneous particle size and concentration values has grown up with continuing discussion of the health effects, of internal combustion engine generated particulate emissions and in particular of Diesel soot emissions. In the present work an aerosol measurement system is described that delivers information about particle size and concentration directly from the undiluted exhaust gas. Using three laser diodes of different wavelengths which form one parallel light beam, each spectral attenuation is analysed by a single detector and the particle diameter and concentration is evaluated by the use of the Mie theory and shown on-line at a frequency of 1 Hz. The system includes an optical long-path-cell (White principle) with an adjustable path length from 2.5 to 15 m, which allows the analysis within a broad concentration range. On-line measurements of the particulate emissions in the hot, undiluted exhaust of Diesel engines are presented under stationary and transient engine’s load conditions. Mean particle diameters well below 100 nm are detected for modern Diesel engines. The measured particle concentration corresponds excellently with the traditional gravimetrical measurements of the diluted exhaust. Additionally, measurements of particle emissions (mostly condensed hydricarbons) from a two-stroke engine are presented and discussed.

Correlation of Measurements of a New Long Optical Path Length Particle Sensor against Gravimetric and Electrical Mobility based Particle Measurements in Diesel Exhaust (2001)

Nikitidis, Michail S. ; Konstandopoulos, Athanasios G. ; Zahoransky, Richard A. ; Laile, Edgar

A prototype multiwavelength sensor able to characterise soot emissions in Diesel exhaust in terms of size and concentration has been tested against other methods for diesel particle measurements like electrical mobility sizing (SMPS) and raw exhaust gravimetric sampling (RES). Measurements carried out with the prototype sensor were correlated with the SMPS by assuming spherical and/or fractal aggregate morphology of the particles. Correlation of RES gravimetric data against the sensor and the SMPS led to the calculation of the solid density for soot particles to be 2.3 gr/cm3.

TLC-Analysis in forensic sciences using a diode-array detector (2001)

Spangenberg, Bernd ; Ahrens, Björn ; Klein, Karl-Friedrich

HPTLC (High Performance Thin Layer Chromatography) is a well known and versatile separation method which shows many advantages when compared to other separation techniques. The method is fast and inexpensive and does not need time-consuming pretreatments. For visualisation of the sample distribution on a HPTLC-plate we developed a new and sturdy HPTLC-scanner. The scanner allows simultaneous registrations of spectra in a range from 198 nm to 612 nm with a spectral resolution of better than 0.8 nm. The on-plate spatial resolution is better than 160 μm. The measurement of 450 spectra in one separation track does not need more than two minutes. The new diode-array scanner offers a fast survey over a TLC-separation and makes various chemometric applications possible. For compound identification a cross-correlation function is described to compare UV sample spectra with appropriate library data. The cross-correlation function herein described can also be used for purity testing. Unresolved peaks can be virtually separated by use of a least squares fit algorithm. In summary, the diode arry system delivers much more information than the commonly used TLC-scanner.

High-performance thin layer chromatography using fiber optics and diode-array detection (2002)

Spangenberg, Bernd ; Klein, Karl-Friedrich ; Mannhardt, Joachim

HPTLC (High Performance Thin Layer Chromatography) is a well known and versatile separation method which shows a lot of advantages and options in comparison to other separation techniques. The method is fast and inexpensive and does not need time-consuming pretreatments. Using fiber-optic elements for controlled light-guiding, the TLC-method was significantly improved: the new HPTLC-system is able to measure simultaneously at different wavelengths without destroying the plate surface or the analytes on the surface. For registration of the sample distribution on a HPTLC-plate we developed a new and sturdy diode-array HPTLC- scanner which allows registration of spectra on the TLC- plates in the range of 198 nm to 610 nm with a spectral resolution better than 1.2 nm. The spatial resolution on plate is better than 160 micrometers . In the spectral mode, the new HPTLC-scanner delivers much more information than the commonly used TLC-scanner. The measurement of 450 spectra of one separation track does not need more than three minutes. However, in the fixed wavelength mode the contour plot can be measured within 15 seconds. In this case, the signal will be summarized and averaged over a spectral range having FWHM from 10 nm to 25 nm depending on the substance under test. The new diode-array HPTLC-scanner makes various chemometric applications possible. The new method can be used easily in clinical diagnostic systems easily, e.g. for blood and uring investigations. In addition, new applications are possible. For example, the rich structured PAHs were studied. Although the separation is incomplete the 16 compounds can be quantified using suitable wavelengths.

Quantitative Bestimmung von Clozapin im Serum mittels Dioden-Array Dünnschichtchromatographie (2003)

Spangenberg, Bernd

Erschließung einer 0.35 Mikrometer Technologie für die Bearbeitung mit Mentor Tools (2003)

Striebel, Markus ; Jansen, Dirk

An der Fachhochschule Offenburg wird der Design-Kit FHO_MTC_CMOS_035_v1.0 erstellt. Mit Hilfe dieses Kits lassen sich Designs in der AMI O.35 Mikrometer Technologie entwerfen. Alle durchgeführten Arbeiten werden durch den Entwurf eines Lottozahlengenerator-Chips verifiziert, der gefertigt wird. Damit sind alle wesentlichen Schritte bekannt, die für die Aufbereitung eines Design-Kits für beliebige Technologien für die Mentor-Tools erforderlich sind. Der Design-Kit wird für alle MPC-Mitglieder freigegen, die eine NDA für AMI bei Europractice unterzeichnet haben.

Redesign eines USB-Controllers in VHDL und Emulation mit einem Mikroprozessorkern auf FPGA (2003)

Kurz, Artur ; Jansen, Dirk

In dieser Arbeit wurde eine USB-Schnittstelle für ein bestehendes Mikrocontroller System FHOP realisiert. Im aktuellen Stand funktioniert das Design zuverlässig in Low Speed Konfiguration. Im Full Speed gibt es noch einige Schwierigkeiten, denn die Kommunikation bricht nach einigen Paket-Transfers zusammen. Durch das Emulieren des Designs auf FPGA wurde die Funktion nachgewiesen. Die nächste Aufgabe wird sein, die Hardware zu optimieren, damit das USB-Modul auch im Full Speed zuverlässig funktioniert. Zusätzlich wird die Software auf der PC Seite optimiert, um höhere Übertragungsraten zu erzielen.

Distributed Multimedia Networking Services: Dynamic Configuration and Change Management (2004)

Zimmermann, Martin

Verifikation eines Mikrokontrollersystems durch Emulation auf FPGA und darauf folgende Synthese und Routing in einer 0,35 µm Technologie (2004)

Bau, Daniel

VHDL-Entwurf eines I²C-Interfaces und Emulation mit einem Mikroprozessorkern auf FPGA (2004)

Bau, Daniel

The flow around interacting rotating spheres of different size (2004)

Bühler, Karl

Webbasierte Online-Datenübertragung (2004)

Feldmann, Thomas

Mehrfachabtastender Stromzustandsregler für höchste dynamische Anforderungen (2004)

Nuß, Uwe

Werbung wird erwachsen – Professionalisierung und Versachlichung für eine Trendbranche (2004)

Breyer-Mayländer, Thomas

Nachhaltigkeitskriterien im Facilitymanagement (2004)

Bollin, Elmar

Influence of different biological fuels on particle emissions of diesel engine (2005)

Zahoransky, Richard A. ; Dorn, Benjamin

Large-Scale Solar Thermal Systems in the Southwest of Germany - Current Status and Future Options in the Frame of the Promotion Program Solarthermie-2000 (2005)

Klingenberger, Uta-Maria ; Bollin, Elmar ; Himmelsbach, Sascha

Sechs Jahre wissenschaftlich-technische Begleitung von thermischen Solargroßanlagen - Ergebnisse und Erfahrungen (2005)

Himmelsbach, Sascha ; Klingenberger, Uta-Maria ; Bollin, Elmar

Energetische Amortisationszeiten bei solarthermischen Großanlagen (2005)

Klingenberger, Uta-Maria ; Bollin, Elmar ; Himmelsbach, Sascha

Dynamic Content Filter of VRML Data for Mobile Phones (2005)

Feißt, Markus ; Christ, Andreas

Adaptive Heterogeneous Learning System (2005)

Feißt, Markus ; Rodrigues dos Santos, Diter ; Mitić, Jelena ; Christ, Andreas

The iSign project started in 2000 as a web-based laboratory setting for students of electrical engineering. In the meantime it has broadened into a heterogeneous learning environment offering learning material, adaptive user settings and access to a simulation tool. All these offerings can be accessed via web and wireless by different clients, such as PCs, PDAs and mobile phones. User adaptive systems offer unique and personalised environment for every learner and therefore are a very important aspect of modern e-learning systems. The iSign project aims to personalise the content structure based on the learner's behaviour, content pattern, policies, and system environment. The second aspect of the recent research and development within this project is the generation of suitable content and presentation for different clients. This generation is based additionally on the user preferences in order to obtain the desirable presentation for a given device. New, valuable features are added to the mobile application, empowering the user not only to control the simulation process with his mobile device but also to input data, view the simulation's output and evaluate the results. Experiences with students have helped to improve functionality and look-and-feel whilst using the iSign system. Our goal is to provide unconstrained, continuous and personalised access to the laboratory settings and learning material everywhere and at anytime with different devices.

The Humboldt Digital Library: Technology in the Service of Travel Literature (2005)

Doherr, Detlev

Energetische Betrachtungen zum Rayleigh-Stokes Problem (2005)

Bühler, Karl ; Zierep, Jürgen

Freie Konvektion im vertikalen Spalt – Analytische Lösungen und numerische Simulation (2005)

Bühler, Karl

Improving the energy yield of power of PV power plants through internet based simulation, monitoring and visualization (2005)

Eicker, Ursula ; Pietruschka, Dirk ; Schumacher, Jürgen ; da Costa Fernandes, Jesus Salazar ; Feldmann, Thomas ; Bollin, Elmar

In this paper, a new method is demonstrated for onlin e remote simulation of photovo ltaic systems. The required communication technology for the data exchange is introduced a nd the methods of PV generato r parameter extraction for the simulation models are analysed. The method shown for parameter extraction from the ma nufacturer data is especially useful for the commissioning procedure, where the measured installed pow er is transferred to standard test conditions using the simulation model and can then be easily compared with the de sign power. At a simulation accuracy of 2% using the software environment INSEL ® any problems with the PV gene rator can reliably be detected. Online simulation of a grid connected PV generator is then carried out during the operation of the photovoltaic plant. The visualisation includes both the monitored and the simulated online data sets, so that a very efficient fault detection scheme i s available. The method is implemented and validated on several grid connected photovolta ic power plants in Germany. It is excellently suited to provide automatic and real time fault detection and significantly impr ove the commissioning procedure for photovoltaic plants of all sizes.

Interaktives Forum zur kooperativen Lernzielkontrolle (2005)

Doherr, Detlev

IDB - Simulation and automation assisted information and control tool for sustainable building operation (2005)

da Costa Fernandes, Jesus Salazar ; Feldmann, Thomas ; Bollin, Elmar

Sustainable Aspects force a building manager to continuous observation of actual states and developments concerning building use, energy and media flows.In the presented approach a communication structure was built up to use different software applications and tools in order to optimize the operation of the building.

"Nachhaltige chemische Produktion" – Das 7. Freiburger Symposium 2005 im Rückspiegel (2005)

Käser, Kurt

The Division Industrial Chemistry of the Swiss Chemical Society organizes periodically a two-day event for the post-graduate education of its members. This event is known as the Freiburger Symposium. This year it focussed on sustainable chemical production. The twelve talks covered the following aspects: ethical needs for sustainability standards, the required, attained, and yet to be attained sustainability goals in chemical industry. Diverse case studies showed the highly developed awareness about the sustainability issue within the chemical community.

Entwicklung eines synchronen Transceivers mit DQPSK Modulation und Soft Shift Keying für eine inductive Übertragung mit Erprobung in einem FPGA (2006)

Jansen, Dirk ; Fawaz, Nidal ; Mogel, Markus

Diesel Engine Particle Emissions: Comparison of Different Plant Oils (2006)

Dorn, Benjamin ; Zahoransky, Richard A. ; Wehmann, Christian

Virtual Reality Data Visualisation on and via Mobile Phones (2006)

Feißt, Markus

Numerische Simulation der freien Konvektion im quadratischen Behälter (2006)

Bühler, Karl

Authoring design patterns for user & device dependent adaptive data presentation (2006)

Feißt, Markus ; Omari, Rami ; Knörle, Oliver

Geothermal Surface Installations – Adjusted Power Plant Technologies (2006)

Zahoransky, Richard A.

Geothermische Möglichkeiten im Oberrheingraben (2006)

Zahoransky, Richard A.

Leistungselektronische Grundlagen (2006)

Nuß, Uwe

Achsenunsymmetrische Stromzustandsregelung mit Dead-Beat-Verhalten nur in der drehmomentbildenden Stromkomponente (2006)

Nuß, Uwe

Regelungstechnik in der Leistungselektronik (2006)

Nuß, Uwe

Nanoparticle Emissions of CR Diesel Engines EURO 4 Fuelled by Plant Oils (2007)

Dorn, Benjamin ; Wehmann, Christian ; Winterhalter, Richard ; Zahoransky, Richard A.

Non-esterified plant oils gain ecological and economical importance, particularly in the EU where it is intended to increase the share of renewable energies. Plant oils do not require any chemical treatment so do not cause secondary pollution. The importance of plant oil will increase in Germany for mobile and stationary applications. The generation co-generation of heat and power is subsidized by the German “Erneuerbares Energiegesetz” and the “Kraft-Wärme-Kopplungsgesetz” when renewable fuels are used such as plant oils.. Plant oils have a much higher viscosity than conventional gas oil. It is mandatory to decrease the oil viscosity by heating prior to injection to assure proper injection and to avoid engine damage due to coke formation in the combustion chamber and at the injection nozzle. The German quality standard of Weihenstephan (RK-Qualitätsstandard 05/2000) for rape seed oil should be followed for use as diesel fuel. The chemical composition of plant oils is appreciably different in comparison to diesel fuels derived from mineral oils suggesting also different emission behavior.

Measurement Unit for Energy Efficient M2M Mobile Communication (2007)

Klemm, Martin ; Sikora, Axel

MI-Learning: ein Rahmenwerk für webbasiertes E-Learning (2007)

Sänger, Volker ; Schmidt, Claudia

Die Macht der Animationen im Unterricht der Naturwissenschaften-eine didaktische Betrachtung (2007)

Curticapean, Dan

Kooperative Projektarbeit zur Entwicklung eines interaktiven CAD-Tutoriums für Maschinenbau und Verfahrenstechnik als Distance Learning Modul (2007)

Doherr, Detlev

Particle and Gaseous Emissions of Diesel Engines Fuelled by Different Non-Esterified Plant Oils (2007)

Dorn, Benjamin ; Wehmann, Christian ; Winterhalter, Richard ; Zahoransky, Richard A.

The particulate matter and gas emissions of several plant oils are analyzed in the hot exhaust gas under various engine conditions at different speeds and loads The measurement data are compared to the emission values of conventional diesel fuel (gas oil). The investigation concentrates on a modern common rail TDI light duty diesel, four cylinders, for passenger cars. The differences in the gas and particulate matter emission - compared to conventional diesel fuel - are remarkably low for the diesel engine which is properly adjusted for the plant oils. Emission data of an old heavy duty diesel engine are also shown for comparison reasons and reveals large differences. Differences are found in the pressures of the indicator diagram, time resolved over the crank angle. Plant oils consistently exhibit a higher cylinder pressure. The TEM investigation confirms the differences found by the LPME (long path multi-wavelength extinction) on-line analysis.

A new platform of an electronic pill with bi-directional communication system for miniaturized and low power biomedical application (2007)

Jansen, Dirk ; Fawaz, Nidal

Mikrobielle Brennstoffzelle – Stromerzeugung aus Abwasser (2007)

Wilke, Andreas ; Zell, Christiane ; Duri, Tobias ; Klotz, M. ; Meier, S.

The identification and quantification of compounds in the gas phase becomes of increasing interest in the context of environmental protection, as well as in the analytical field. In this respect, the high extinction coefficients of vapours and gases in the ultraviolet wavelength region allow a very sensitive measurement system. In addition, the increased performance of the components necessary for setting up a measurement system, such as fibres, light sources and detectors has been improved. In particular the light sources and detectors offer improved stability, and the deep UV performance and solarisation resistance of fused silica fibres allow have been significantly optimized in the past years. Therefore a compact and reliable detection system with high measuring accuracy is developed. Within this paper possible applications of the system under development and recent results will be discussed.

Fibre-optic UV systems for gas and vapour analysis (2007)

Eckhardt, Hanns Simon ; Klein, Karl-Friedrich ; Spangenberg, Bernd ; Sun, Tong ; Grattan, Kenneth T.V.

The identification and quantification of compounds in the gas phase becomes of increasing interest in the context of environmental protection, as well as in the analytical field. In this respect, the high extinction coefficients of vapours and gases in the ultraviolet wavelength region allow a very sensitive measurement system. In addition, the increased performance of the components necessary for setting up a measurement system, such as fibres, light sources and detectors has been improved. In particular the light sources and detectors offer improved stability, and the deep UV performance and solarisation resistance of fused silica fibres allow have been significantly optimized in the past years. Therefore a compact and reliable detection system with high measuring accuracy is developed. Within this paper possible applications of the system under development and recent results will be discussed.

Der "Deal" mit der Realität - Medienwirklichkeit(en) und die Verantwortung der Lehrenden in Medienstudiengängen (2008)

Lankau, Ralf

Enhanced Telemetry System using CP-QPSK Band-Pass Modulation Technique Suitable for Smart Pill Medical Application (2008)

Fawaz, Nidal ; Jansen, Dirk

Bürogebäude mit Zukunft - energetische Bewertung des Solar Info Center (SIC) Freiburg. (2008)

da Costa Fernandes, Jesus Salazar ; Feldmann, Thomas ; Bollin, Elmar

Optimierung des Gebäudebetriebs durch die Auswertung von Wetterprognosen (2008)

Feldmann, Thomas ; da Costa Fernandes, Jesus Salazar ; Bollin, Elmar

Development of an Electro Physiological Front End with SPI-Bus Connection (2008)

Bau, Daniel

Nonlinear surface acoustic waves: Theory (2008)

Mayer, Andreas

A theoretical description is given for the propagation of surface acoustic wave pulses in anisotropic elastic media subject to the influence of nonlinearity. On the basis of nonlinear elasticity theory, an evolution equation is presented for the surface slope or the longitudinal surface velocity associated with an acoustic pulse. It contains a non-local nonlinearity, characterized by a kernel that strongly varies from one propagation geometry to another due to the anisotropy of the substrate. It governs pulse shape evolution in homogeneous halfspaces and the shapes of solitary surface pulses that exist in coated substrates. The theory describing nonlinear Rayleigh-type surface acoustic waves is extended in a straightforward way to surface waves that are localized at a one-dimensional acoustic waveguide like elastic wedges.

Development of a Physiological Front End with SPI Bus Connection (2008)

Bau, Daniel

Im Rahmen einer Master Thesis wurde ausgehend von einem vorhandenen System On Chip Design, welches eingehende EKG-Datensignale verarbeitet, das bestehende System so erweitert dass es komplett über den standardisierten SPI-Bus steuerbar und auslesbar ist.

RFID- Frontend ISO 15693 (2008)

Volk, Tobias

Operationssystem für den SIRIUS Softcore Processor (2008)

Zowislok, Florian

Non-Esterified Plant Oils as Fuel -Engine Characteristics, Emission Behaviour and Health Impact of PM- (2009)

Dorn, Benjamin ; Zahoransky, Richard A.

Plant oils may be used as a sustainable, nearly CO2neutral fuel for diesel engines. This work investigates experimentally the particulate and gaseous emissions of diesel engines fuelled with different non-esterified, pure plant oils. The data are collected from three engines: a) Common rail 1.7 liter passenger car engine from Opel AG b) 12.8 liter truck engine from VOLVO c) Truck engine from MAN AG. The emissions of the MAN engine have been used to perform AMES tests to analyze possible health impacts of plant oil operation. Finally, all emission results with plant oils have been compared to traditional gas oils.

A phenomenological model for the material behaviour of elastomers due to multi network chains; Constitutive Models for Rubber VI (2009)

Ziegler, Christian

Grafische Oberfläche für SIRIUS Prozessorkern auf FPGA (2009)

Kreker, Andreas ; Durrenberger, Marc ; Bau, Daniel ; Jansen, Dirk

Software-Metriken gezielt einsetzen (2009)

Fischer, Daniel ; Drosdezki, Eugenia ; Schuraev, Konstantin

Dynamic Dispatching and Transport Optimization Real-World Experience with Perspectives on Pervasive Technology Integration (2009)

Greenwood, Dominic ; Dannegger, Christian ; Dorer, Klaus ; Calisti, Monique

Predictive Operation of Sustainable Buildings (2009)

Feldmann, Thomas ; Bollin, Elmar ; da Costa Fernandes, Jesus Salazar

Prädiktive Betriebsführung solarthermischer Anlagen. Wetterprognosen, Nutzerprognosen, Anlagensimulation (2009)

Scheck, Eva ; Bollin, Elmar ; Huber, Klaus

Solarunterstützte-CO2-neutrale Nahwärmeversorgung in Holzgerlingen Betriebserfahrungen und Anlagen-Optimierungen (2009)

Scheck, Eva ; Bollin, Elmar ; Huber, Klaus

Der UMC 0.18 Design Flow am Beispiel eines PDA- Processor -IC s (2009)

Bau, Daniel ; Jansen, Dirk

Hybridantriebe für industrielle Anwendungen (2009)

Zahoransky, Richard A. ; Böhler, Frank

University for Children – The Magic of Light (2009)

Curticapean, Dan

The University for Children is a very successful event aiming to spark children‧s interest in science, in this particular lecture in Optics and Photonics. It is from brain research that we know about the significant dependence of successful learning on the fun factor. Researchers in this field have shown that knowledge acquired with fun is stored for a longer time in the long-term memory and can be used both more efficiently and more creatively [1], [2]. Such an opportunity to inspire the young generation for science must not be wasted. The world of Photonics and Optics provides us with a nearly inexhaustible source of opportunities of this kind.

Preface: International Marketing Campaign of the Research Cluster zafh.net (2009)

Bollin, Elmar

Non-Esterified Plant Oils as Fuel -Engine Charakteristics, Emission and Mutagenic effects of PM- (2009)

Dorn, Benjamin ; Zahoransky, Richard A.

Plant oils may be used as a sustainable, nearly CO2 neutral fuel for diesel engines. This work investigates experimentally the particulate and gaseous emissions of diesel engines fuelled with non-esterified, pure plant oils with the quality standard of DIN V 51605 (Weihen-stephan RK-Qualitätsstandard 05/2000). The data are collected from three engines: Common rail passenger car engine from OPEL AG Truck engine from VOLVO Truck engine from MAN AG All engines have been correctly adjusted to plant oil operation. The OPEL and VOLVO engines served for the basic investigations. The emissions of the MAN engine have been used to perform AMES tests to analyze possible health impacts of plant oil operation. The experimental data show a reduction of particulate matter compared to traditional gasoil which may yield up to 50 % for. The particulate matter shows same primary particle sizes but the agglomerates as collected on TEM grids are different - the plant oil soot particles tend to form larger aggregates [4]. The gaseous emissions of CO and hydrocarbons HC are generally lower compared to the operation with gasoil. However, the NOX emissions are slightly higher. This may be contributed to the measured higher combustion chamber pressures and temperatures when fuelled by plant oils. Emission samples have been extracted from ESC cycles of 13 step tests to perform the AMES test which give indication on carcinogen substances. The AMES test results gave no indication of mutagenic effects exceeding the detection limits. No significant differences could be found comparing the emissions of plant oil and gasoil operation. Thus, it can be stated that the emission from plant oil operation does not have a health impact different to traditional gas oil. This is in contrast to some other publications — a deeper insight shows that these investigations did not properly modify the engine for plant oils. It is mandatory to make the engine modification to pre-warm the plant oils to approx. 90°C prior to injection. The engine's warm-up phase needs special care to avoid any coking at the injection system and combustion chamber surfaces. The publications where a higher health risk was claimed to be found in the exhaust of plant oil fuels, did not pre-warm the plant oils — cold plant oils have been injected in the combustion chamber instead. This results in incomplete atomization and incomplete combustion with a lot of hazardous emission species (see also [4,11]. Such an operation will damage the engine after relatively short times and is, therefore, not realistic. The investigated fuels had some influence on the engine characteristics. Higher temperatures and pressures in the cylinder have been detected for some plant oils compared to gasoil. This increase is explained by the higher oxygen content within the plant oils.

Mobile learning a new Paradigm of e-Learning in Optics and Photonics (2009)

Christ, Andreas ; Feißt, Markus ; Curticapean, Dan

The developed solution enables the presentation of animations and 3D virtual reality (VR) on mobile devices and is well suited for mobile learning, thus creating new possibilities in the area of e-learning worldwide. Difficult relations in physics as well as intricate experiments in optics can be visualised on mobile devices without need for a personal computer.

Erste Ergebnisse und Betriebserfahrungen des Detailmonitorings einer solarthermischen Anlage zur Unterstützung der Kälteversorgung eines Büro- und Verwaltungsgebäudes (2009)

Bollin, Elmar ; Huber, Klaus ; Scheck, Eva

Die Hochschule Offenburg begleitet seit Juli 2006 in Zusammenarbeit mit dem Fraunhofer ISE in Freiburg, die solar unterstützte Klimatisierung der Festo AG & Co. KG in Esslingen im Rahmen des Forschungsvorhabens Solarthermie2000plus. Dabei wurde die bereits bestehende Adsorptionskälteanlage, die bisher mit Gaskesseln und Kompressorenabwärme betrieben wurde, durch eine Solaranlage als dritte Wärmequelle ergänzt.

Smart Houses in the Smart Grid (2009)

Kok, Koen ; Karnouskos, Stamatis ; Nestle, David ; Dimeas, Aris ; Weidlich, Anke ; Warmer, Cor ; Strauss, Philipp ; Buchholz, Britta ; Drenkard, Stefan ; Hatziargyriou, Nikos ; Lioliou, Vali

Innovative technologies and concepts will emerge as we move towards a more dynamic, service-based, market-driven infrastructure, where energy efficiency and savings can be facilitated by interactive distribution networks. A new generation of fully interactive Information and Communication Technologies (ICT) infrastructure has to be developed to support the optimal exploitation of the changing, complex business processes and to enable the efficient functioning of the deregulated energy market for the benefit of citizens and businesses. The architecture of such distributed system landscapes must be designed and validated, standards need to be created and widely supported, and comprehensive, reliable IT applications will need to be implemented. The collaboration between a smart house and a smart grid is a promising approach which, with the help of ICT can fully unleash the capabilities of the smart electricity network.

Cache-Speicher für den Softprozessor SIRIUS mit DDR-Interface (2009)

Zowislok, Florian

Betriebsoptimierung von Gebäuden und Anlagen (2009)

Feldmann, Thomas

Semi-invasives elektrokardiographisches Mindestmaß zur Positionierung der linksventrikulären Elektrode (2010)

Kroll, Katharina ; Rotter, Kirsten-Maria ; Ismer, Bruno ; Heinke, Matthias ; Akin, Ibrahim ; Schell-Dieckel, Stephanie ; Trautwein, Ulrich ; Melzer, Christoph ; Weber, Frank ; Nienaber, Christoph A.

Langzeitmonitoring einer solarthermischen Anlage zur Unterstützung der Kälteversorgung eines Büro- und Verwaltungsgebäudes (2010)

Huber, Klaus ; Bollin, Elmar ; Scheck, Eva

Semi-invasive determination of interventricular and intraleftventricular conduction delay in CRT patients (2010)

Ismer, Bruno ; Rotter, Kirsten-Maria ; Heinke, Matthias ; Akin, Ibrahim ; Kroll, Katharina ; Schell-Dieckel, Stephanie ; Trautwein, Ulrich ; Voß, Wolfgang ; Melzer, Christoph ; Weber, Frank ; Peters, Ralf ; Nienaber, Christoph A.

Using guideline parameters for indication of cardiac resynchronization therapy (CRT), only about two thirds of the patients improve clinically. Unfortunately both, surface ECG and echo are uncertain to predict CRT response. To better characterize cardiac desynchronization in heart failure, interventricular (IVCD) and intra-leftventricular conduction delays (ILVCD) were measured by esophageal left ventricular electrogram (LVE). Recordings in 43 CRT patients (34m, 9f, age: 64.7 ± 9.5yrs) evidenced only weak correlation between IVCD and QRS of 0.53 and between ILVCD and QRS of 0.33. This demonstrated that QRS duration is not a reliable indicator of desynchronization. Therefore, the study resulted into development of LVE feature for a programmer with implant support device. It can be used interoperatively to guide the left ventricular electrode location in order to increase responder rate in CRT.

Application of 3D colour printing for the rapid prototyping of functional models; Innovative developments in design and manufacturing (2010)

Junk, Stefan ; Sämann-Sun, Jing

Bipolar Transesophageal Left Atrial Electrocardiography and Rapid Left Atrial Pacing with Hemispherical Directed Electrical Pacing Field for Evaluation and Termination of Atrial Flutter (2010)

Heinke, Matthias ; Ismer, Bruno ; Heinke, Tobias ; Kühnert, Helmut ; Surber, Ralf ; Prochnau, Dirk ; Haltenberger, Anna ; Dannberg, Gudrun ; Figulla, Hans Reiner

Termination of atrial flutter (AFL) is not possible in all AFL patients (P) with transesophageal left atrial pacing (TLAP) with undirected electrical pacing field (EPF) and high atrial pacing threshold. Purpose of the study was to evaluate bipo-lar transesophageal left atrial electrocardiography (TLAE) and TLAP with directed EPF for evaluation and termination of AFL with and without simultaneous transesophageal echocardiography (TEE). Methods: AFL P were analysed using either a TO electrode with one cylindrical (CE) and three or seven hemispherical electrodes (HE) or TEE electrode with four HE (Osypka, Rheinfelden, Germany). Burst TLAP cycle length was between 200msand 50ms. Results: AFL cycle length was 233±30 ms with mean ventricular cycle length of 540±149 ms. AFL could be terminated by rapid bipolar TLAP with directed EPF using HE-HE and CE-HE with induction of atrial fibrillation (AF), induction of AF and spontaneous conversion to sinus rhythm and direct conversion to sinus rhythm. Directed EPF was simulated with finite element method. Conclusions: AFL can be evaluated by bipolar TLAE. AFL can be terminated with rapid TLAP with directed EPF with and without simultaneous TEE. Bipolar TLAE with rapid TLAP is a safe, simple and useful method for evaluation and termination of AFL.

Bipolar Transesophageal Left Ventricular Electrocardiography and Directed Electrical Pacing with Cylindrical and Hemispherical Electrodes to Select Patients for Biventricular Pacing (2010)

Heinke, Matthias ; Ismer, Bruno ; Heinke, Tobias ; Surber, Ralf ; Haltenberger, Anna ; Kühnert, Helmut ; Eisenträger, Daniela ; Lorenz, Martin ; Prochnau, Dirk ; Dannberg, Gudrun ; Figulla, Hans Reiner

Cardiac resynchronisation therapy (CRT) with biventricular pacing (BV) is an established therapy for heart failure (HF) patients with interventricular conduction delay (IVCD). The aim of the study was to evaluate transesophageal IVCD and left ventricular (LV) pacing with directed electrical pacing field (EPF) in HF patients. Methods: HF patients were analysed with bipolar transesophageal LV electrocardiogram recording and LV pacing with constant voltage stimulus output, 4 ms stimulus duration, distal cylindrical electrode (CE) and seven 6 mm hemispherical electrodes (HE) with 15 mm electrode distance (TO, Dr. Osypka, Rheinfelden, Germany). Results: LV electrocardiogram recording with HE-HE and CE-HE evaluated a mean IVCD of 79.9 ± 36.7 ms. Directed EPF with CE-HE and HE-HE allowed LV VAT (n=12) and LV D00 pacing (n=5) with a mean effective capture output of 97.35 ± 6.64 V. In 15 responders with IVCD of 87 ± 33 ms arterial pulse pressure (PP) increased from 65 ± 24 mmHg to 79 ± 27 mmHg (p < 0.001). EPF was simulated with finite element method. Conclusions: Transesophageal LV electrocardiography and directed EPF pacing with CE and HE allowed the evaluation of IVCD and PP to select patients for BV pacing.

Vergleich der hämodynamischen Reaktion auf VV-Delay Änderungen bei Sinusrhythmus und Vorhofflimmern (2010)

Ismer, Bruno ; Heinke, Matthias ; Kroll, Katharina

Left ventricular tip versus superior vena cava coil electrogram – a new approach for automatic AV delay optmization in cardiac resynchronization (2010)

Ismer, Bruno ; Rösch, Lena ; Kroll, Katharina ; Heinke, Matthias ; Körber, Thomas ; Weber, Frank ; Peters, Ralf ; Nienaber, Christoph A.

AV delay (AVD) optimization can improve hemodynamics and avoid nonresponding to cardiac resynchronization therapy (CRT). AVD can be approximated by the sum of the individual implant-related interatrial conduction interval and a mean electromechanical interval of about 50ms. We searched for methods to facilitate automatic, implant-based AV delay optimization. In 25 patients (19m, 6f, age: 65±8yrs.) with Medtronic Insync III Marquis CRT-D series systems and left ventricular electrode at lateral or posterolateral wall, we determined interatrial conduction intervals by telemetric left ventricular tip versus superior vena cava coil electrogram (LVCE). Compared with esophageal measurements, the duration of optimal AV delay by LVCE showed good correlation (k=0.98, p=0.01) with a difference of 1.5±4.9ms, only. Therefore, LVCE is feasible to determine interatrial conduction intervals in order to automate AV delay optimization in CRT-D pacing promising increased accuracy compared to other algorithms.

Programmer based interatrial conduction interval measurement simplifies AV delay programming in cardiac resynchronization therapy (2010)

Kleimenhagen, Frank ; Ismer, Bruno ; Heinke, Matthias ; Hoppert, Thomas ; Körber, Thomas ; Weber, Frank ; Peters, Ralf ; Nienaber, Christoph A.

AV delay (AVD) optimization is mandatory in cardiac resynchronization (CRT) for heart failure. Several time consuming methods exist. We initialized development of left-atrial electrogram (LAE) feature for Biotronik ICS3000 programmer. It can be utilized to approximate optimal AV delay in CRT patients with pacing systems irrespective of make and model. Using this feature, we studied the share of interatrial conduction intervals (IACT) on individual echo AVD in 45 CRT patients (34m, 11f, mean age 69±6yrs.). The percentage of IACT on optimal echo AVD resulted in44.5±22.1% for VDD and 70.7±10.9% for DDD operation. In all patients, optimal echo AVDs exceeded the individual IACT by a duration of 52.5±33.3ms (p<0.001), at mean. Therefore, if AV delay optimization is not possible or not practicable in CRT patients, AVD should be approximated by individually measuring IACT and adding about 50ms.

Semi-invasive Charakterisierung der interventrikulären und intra-linksventrikulären Leitungsverzögerung bei Herzinsuffizienz-Patienten (2010)

Rotter, Kirsten-Maria ; Ismer, Bruno ; Heinke, Matthias

Exhaust Gas Aftertreatment by Micro Waves (2010)

Reith, Jürgen ; Zahoransky, Richard A.

Konzeption und Entwicklung eines Delta-Sigma-Wandlers in VHDL (2010)

Riske, Alexander ; Jansen, Dirk ; Volk, Tobias

Discussing the Potential of Hybrids for on and off Road Emissions Reduction Diesel Emissions (2010)

Zahoransky, Richard A. ; Ruhkamp, Ludger ; Akikawa, Fumio

Active Noise Control Using the TMS320C6713 DSP (2010)

Reich, Werner ; Hilterhaus, Ralf ; Backes Hertz, Andrei Luiz

This paper gives an overview of the implementation of an Active Noise Control system on the TMS320C6713 Digital Signal Processor from Texas Instruments in the Digital Signal Processing Lab at Hochschule Offenburg, Germany. This system is implemented considering some non-ideal environmental conditions on a real system instead of being limited to computer simulations. Changes over time on the physical acoustical path as well as reverberation and variation on the power of the reference signal can strongly degrade the performance of the system or even lead to instability. In order to try to minimize these effects, the Active Noise Control system was designed to support a fast and easy implementation and evaluation of different algorithms on the DSP in real-time. In Section 1 a brief introduction about active noise control system is given and in section 2 the basic algorithm is described. In section 3 the implementation of the system is described and in section 4 some final considerations are given.

Von Peers, Pop und Porn: Neue Medien und Formen der Öffentlichkeit (2010)

Lankau, Ralf

Gehören Sie zur „generation upload“? Laden Sie ihre privaten Bilder auf Flickr hoch und stellen Videos bei YouTube ein? Downloaden Sie MPEG-Files auf ihr Handheld oder spielen Sie ständig neue, echt witzige Apps auf ihr SmartPhone? Klicken Sie sich ihre Freunde in Facebook, MySpace oder StudiVZ zusammen, um rund um die Uhr zu chatten und zu bloggen? Oder twittern Sie eher und haben für Ihren Tweed schon Follower? Gruscheln Sie Menschen, deren Foto ihnen gefällt und sperren den Kontakt per Mausklick, wenn er oder sie doch nicht so nett ist? Software und Filme besorgen Sie sich von ihren Peers über Bit-Torrent-Tracker wie Pirate Bay? Lustig finden Sie „flash mobs“, weniger witzig „cyber mobs“? Oder sind Sie der eher rabiate Typ, der fremde Rechner hackt, spammt und „Google bombs“ platziert? Oder fragen Sie sich gerade, von was ich hier überhaupt rede? Willkommen in der „brave new world – of media”.

Pairwise Testing - Unentdeckten Fehlern auf der Spur (2010)

Fischer, Daniel ; Seitel, D.

Ermüdungsfestigkeit von Zahnwellenverbindungen mit freiem und gebundenem Auslauf (2010)

Daryusi, Ali ; Schlecht, Berthold ; Lohrengel, Armin

Design for Testability (DFT) Strukturen für ASIC-Design und ihre Emulation auf FPGA (2010)

Dusch, Benjamin

[...]Bezug genommen wird hauptsächlich auf die Einführung der DFT-Strukturen in das ASIC-Design des „Rolling Dice“. Ein Vergleich von Aufwand gegenüber Nutzen bei Implementierung von DFT-Strukturen in „kleine“ gegenüber „große“ ASIC-Design bildet ein wichtiges Fazit.

Can the accuracy of intracardiac electrogram based CRT optimization be improved? (2011)

Rösch, Lena ; Heinke, Matthias ; Kleimenhagen, Frank ; Melzer, Christoph ; Fink, Rudiger ; Weber, Frank ; Ismer, Bruno

Introduction: To simplify AV delay (AVD) optimization in cardiac resynchronization therapy (CRT), we reported that the hemodynamically optimal AVD for VDD and DDD mode CRT pacing can be approximated by individually measuring implant-related interatrial conduction intervals (IACT) in oesophageal electrogram (LAE) and adding about 50ms. The programmer-based St Jude QuickOpt algorithm is utilizing this finding. By automatically measuring IACT in VDD operation, it predicts the sensed AVD by adding either 30ms or 60ms. Paced AVD is strictly 50ms longer than sensed AVD. As consequence of those variations, several studies identified distinct inaccuracies of QuickOpt. Therefore, we aimed to seek for better approaches to automate AVD optimization. Methods: In a study of 35 heart failure patients (27m, 8f, age: 67±8y) with Insync III Marquis CRT-D systems we recorded telemetric electrograms between left ventricular electrode and superior vena cava shock coil (LVtip/SVC = LVCE) simultaneously with LAE. By LVCE we measured intervals As-Pe in VDD and Ap-Pe in DDD operation between right atrial sense-event (As) or atrial stimulus (Ap), resp., and end of the atrial activity (Pe). As-Pe and Ap-Pe were compared with As-LA an Ap-LA in LAE, respectively. Results: End of the left atrial activity in LVCE could clearly be recognized in 35/35 patients in VDD and 29/35 patients in DDD operation. We found mean intervals As-LA of 40.2±24.5ms and Ap-LA of 124.3±20.6ms. As-Pe was 94.8±24.1ms and Ap-Pe was 181.1±17.8ms. Analyzing the sums of As-LA + 50ms with duration of As-Pe and Ap-LA + 50ms with duration of Ap-Pe, the differences were 4.7±9.2ms and 4.2±8.6ms, resp., only. Thus, hemodynamically optimal timing of the ventricular stimulus can be triggered by automatically detecting Pe in LVCE. Conclusion: Based on minimal deviations between LAE and LVCE approach, we proposed companies to utilize the LVCE in order to automate individual AVD optimization in CRT pacing.

In-vivo and in-vitro comparison of implant-based CRT optimization - What provide new algorithms? (2011)

Riedel, Björn ; Heinke, Matthias ; Weber, Frank ; Nienaber, Christoph A. ; Ismer, Bruno

Introduction: In cardiac resynchronization therapy (CRT), individual AV delay (AVD) optimization can effectively increase hemodynamics and reduce non-responder rate. Accurate, automatic and easily comprehensible algorithms for the follow-up are desirable. QuickOpt is the first attempt of a semi-automatic intracardiac electrogram (IEGM) based AVD algorithm. We aimed to compare its accuracy and usefulness by in-vitro and in-vivo studies. Methods: Using the programmable ARSI-4 four-chamber heart rhythm and IEGM simulator (HKP, Germany), the QuickOpt feature of an Epic HF system (St. Jude, USA) was tested in-vitro by simulated atrial IEGM amplitudes between 0.3 and 3.5mV during both, manual and automatic atrial sensing between 0.2 and 1.0mV. Subsequently, in 21 heart failure patients with implanted biventricular defibrillators, QuickOpt was performed in-vivo. Results of the algorithm for VDD and DDD stimulation were compared with echo AV delay optimization. Results: In-vitro simulations demonstrated a QuickOpt measuring accuracy of ± 8ms. Depending on atrial IEGM amplitude, the algorithm proposed optimal AVD between 90 and 150ms for VDD and between 140 and 200ms for DDD operation, respectively. In-vivo, QuickOpt difference between individual AVD in DDD and VDD mode was either 50ms (20pts) or 40ms (1pt). QuickOpt and echo AVD differed by 41 ± 25ms (7 – 90ms) in VDD and by 18 ± 24ms (17-50ms) in DDD operation. Individual echo AVD difference between both modes was 73 ± 20ms (30-100ms). Conclusion: The study demonstrates the value of in-vitro studies. It predicted QuickOpt deficiencies regarding IEGM amplitude dependent AVD proposals constrained to fixed individual differences between DDD and VDD mode. Consequently, in-vivo, the algorithm provided AVD of predominantly longer duration than echo in both modes. Accepting echo individualization as gold standard, QuickOpt should not be used alone to optimize AVD in CRT patients.

Programmer feature to quantify interventricular desynchronization and interatrial conduction intervals (2011)

Rotter, Kirsten-Maria ; Rösch, Lena ; Heinke, Matthias ; Kleimenhagen, Frank ; Weber, Frank ; Peters, Ralf ; Nienaber, Christoph A. ; Ismer, Bruno

Introduction: Patient selection for cardiac resynchronization therapy (CRT) requires quantification of left ventricular conduction delay (LVCD). After implantation of biventricular pacing systems, individual AV delay (AVD) programming is essential to ensure hemodynamic response. To exclude adverse effects, AVD should exceed individual implant-related interatrial conduction times (IACT). As result of a pilot study, we proposed the development of a programmer-based transoesophageal left heart electrogram (LHE) recording to simplify both, LVCD and IACT measurement. This feature was implemented into the Biotronik ICS3000 programmer simultaneously with 3-channel surface ECG. Methods: A 5F oesophageal electrode was perorally applied in 44 heart failure CRT-D patients (34m, 10f, 65±8 yrs., QRS=162±21ms). In position of maximum left ventricular deflection, oesophageal LVCD was measured between onsets of QRS in surface ECG and oesophageal left ventricular deflection. Then, in position of maximum left atrial deflection (LA), IACT in VDD operation (As-LA) was calculated by difference between programmed AV delay and the measured interval from onset of left atrial deflection to ventricular stimulus in the oesophageal electrogram. IACT in DDD operation (Ap-LA) was measured between atrial stimulus and LA.. Results: LVCD of the CRT patients was characterized by a minimum of 47ms with mean of 69±23ms. As-LA and Ap-LA were found to be 41±23ms and 125±25ms, resp., at mean. In 7 patients (15,9%), IACT measurement in DDD operation uncovered adverse AVD if left in factory settings. In this cases, Ap-LA exceeded the factory AVD. In 6 patients (13,6%), IACT in VDD operation was less than or equal 10ms indicating the need for short AVD. Conclusion: Response to CRT requires distinct LVCD and AVD optimization. The ICS3000 oesophageal LHE feature can be utilized to measure LVCD in order to justify selection for CRT. IACT measurement simplifies AV delay optimization in patients with CRT systems irrespective of their make and model.

Instrumente des Dialogmarketing im Maschinenbau (2011)

Greschuchna, Larissa

Analysing-software for impedance and electrocardiography – what is currently possible? (2011)

Haltenberger, Anna ; Eisenträger, Daniela ; Ismer, Bruno ; Solbrig, Olaf ; Querengässer, Jürgen ; Winkler, Andreas ; Allmann, Jakob ; Töpfer, Anja ; Figulla, Hans Reiner ; Heinke, Matthias

Introduction: Cardiac resynchronization therapy (CRT) with biventricular (BV) pacing is an established therapy for heart failure (HF) patients with ventricular desynchronisation and reduced left ventricular (LV) function. The aim of this study was to evaluate preejection period (PEP) and left ventricular ejection time (LVET) with transthoracic signal averaging impedance and electrocardiography in HF patients with and without BV pacing. Methods: 10 HF patients (age 68.9 ± 8 years; 2 females, 9 males) with New York Heart Association (NYHA) class 2,9 ± 0.5, 30.9 ± 10.5 % LV ejection fraction and 159.4 ± 22.9 ms QRS duration were analysed with transthoracic impedance and electrocardiography (Cardioscreen Medis, Ilmenau, Germany) and novel National Intruments LabView 2009 signal averaging software. One day after BV pacing device implantation, AV and VV delays were optimized by transthoracic impedance cardiography and stroke volume (SV) and cardiac output (CO) were gained by Cardioscreen. Results: Transthoracic impedance and electrocardiography AV and VV delay opimization was possible in all HF patients with BV pacing devices (n= 10). PEP was 154 ± 24ms without BV pacing and measured between onset of QRS in the surface electrocardiogram and onset of ventricular deflection in the impedance cardiogram. LVET was 342 ± 65ms without BV pacing and measured between onset and offset of ventricular deflection in the impedance cardiogram. The use of optimal AV and VV delay BV pacing resulted in improvement of SV from 64.1 ± 26.5 ml to 94.1 ± 33.96 ml (P < 0.05) and CO from 4.05 ± 1.36 l/min to 6.44 ± 1.56 l/min (P < 0.05). Conclusion: PEP and LVET may be useful parameters of ventricular Desynchronisation. AV and VV delay optimized BV pacing improve SV and CO. Impedance and electrocardiography with LabView 2009 signal averaging may be a simple and useful technique to optimize CRT.

Transesophageal left cardiac electrocardiography for evaluation of interventricular and interatrial conduction delay before and after premature ventricular contraction in heart failure patients (2011)

Haltenberger, Anna ; Heinke, Matthias ; Ismer, Bruno ; Kühnert, Helmut ; Küthe, Friedhelm ; Eisenträger, Daniela ; Surber, Ralf ; Prochnau, Dirk ; Lorenz, Martin ; Figulla, Hans Reiner

Introduction: Cardiac resynchronization therapy (CRT) with biventricular pacing is an established therapy for heart failure (HF) patients with sinus rhythm and ventricular desynchronisation. The aim of this study was to evaluate interventricular conduction delay (IVCD) and interatrial conduction delay (IACD) before and after premature ventricular contractions (PVC) in HF patients. Methods: 13 HF patients (age 68 ± 10 years; 2 females, 11 males) with New York Heart Association functional class 2,8 ± 0.5, left ventricular (LV) ejection fraction 28,6 ± 12,6 %, 154 ± 25 ms QRS duration and PVC were analysed with bipolar transesophageal LV and left atrial electrogram recording and National Instruments LabView 2009 software. The level of significance of the t-test is 0,005. Results: QRS duration increases during PVC (188 ± 32 ms) in comparison to the beat before (154 ± 25 ms, P = ) and after PVC (152 ± 25 ms,). IVCD increases during PVC up to 65 ± 33 ms (51 ± 19 ms in the beat before PVC, P=0.18, 49 ± 19 ms after PVC, P = 0.12). Intra-LV delay of 90 ± 16 ms is not different in the beat before PVC, 90 ± 14 ms during PVC (P = 0.99) and 94 ± 16 ms in the beat after PVC (P = 0.38). IACD is not significantly PVC influenced (67 ± 12 ms before PVC and 65 ± 13 ms after PVC, P = 0.71). Intra-left atrial conduction delay is not significant longer during PVC (57 ± 28 ms) than in the beat before PVC (54 ± 13 ms, P = 0.51) or after PVC (54 ± 8 ms, P = 0.45). PQ duration increases significantly after PVC (224 ± 95 ms) in comparison to the beat before PVC (176± 29 ms, P =...). Conclusion: Transesophageal left cardiac electrocardiography with LabView 2009 software can improve evaluation of IVCD and IACD before, during and after PVC in HF patient selection for CRT.

Usability of transesophageal electrical intra-left ventricular and interventricular conduction delay to improve patient selection for cardiac resynchronization therapy (2011)

Heinke, Matthias ; Ismer, Bruno ; Kühnert, Helmut ; Heinke, Tobias ; Surber, Ralf ; Küthe, Friedhelm ; Haltenberger, Anna ; Lorenz, Martin ; Eisenträger, Daniela ; Prochnau, Dirk ; Figulla, Hans Reiner

Introduction: Cardiac resynchronization therapy (CRT) with biventricular pacing (BV) is an established therapy for heart failure (HF) patients (P) with ventricular desynchronisation, but not all patients improved clinically. Aim of this study was to evaluate electrical intra-left ventricular conduction delay (LVCD) and interventricular conduction delay (IVCD), to better select patients for CRT. Methods: 65 HF patients (age 63.4 ± 10.6 years; 7 females, 58 males) with New York Heart Association (NYHA) class 3 ± 0.2, 24.4 ± 6.7 % left ventricular (LV) ejection fraction and 167.4 ± 35.6 ms QRSD were included. Esophageal TO Osypka focused hemispherical electrodes catheter was perorally applied in position of maximum LV deflection to measure LVCD between onset and offset of LV deflection and IVCD between earliest onset of QRS in the 12-channel surface ECG and onset of LV deflection in the focused bipolar transesophageal LV electrogram. Results: There were 50 responders with LVCD of 76.5 ± 20.4 ms, IVCD of 80.5 ± 26.1 ms (P=0.34) and QRSD of 171 ± 37.7 ms. 15 non-responders had longer LVCD of 90 ± 28.5 ms (P = 0.045), shorter IVCD of 50.1 ± 29.1 ms (P < 0.001) and QRSD of 155.3 ± 25 ms (P=0.14). During 21.3 ± 20.3 month BV pacing follow-up, the responder`s NYHA classes improved from 3 ± 0.2 to 2. ± 0.3 (P < 0.001) whereas the non-responders NYHA classes did not improve from 3 ± 0.2 to 2.9 ± 0.3 (P = 0.43) during 15.7 ± 13.9 month BV pacing follow-up (53 Boston, 10 Medtronic and 2 St. Jude CRT devices). Conclusion: Determination of electrical LVCD and IVCD by focused bipolar transesophageal LV electrogram recording may be an additional useful technique to improve patient selection for CRT.

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