@article{RiglingBiglerEilmannetal.2012, author = {Rigling, Andreas and Bigler, Christof and Eilmann, Britta and Feldmeyer-Christe, Elisabeth and Gimmi, Urs and Ginzler, Christian and Graf, Ulrich and Mayer, Phillip and Vacchiano, Giorgio and Weber, Pascal and Wohlgemuth, Thomas and zweifel, Roman and Dobbertin, Matthias}, title = {Driving factors of a vegetation shift from Scots pine to pubescent oak in dry Alpine forests}, series = {Global Change Biology}, volume = {19}, journal = {Global Change Biology}, number = {1}, publisher = {Wiley-Blackwell}, address = {Oxford}, issn = {1354-1013 (Print)}, doi = {10.1111/gcb.12038}, pages = {229 -- 240}, year = {2012}, abstract = {An increasing number of studies have reported on forest declines and vegetation shifts triggered by drought. In the Swiss Rhone valley (Valais), one of the driest inner-Alpine regions, the species composition in low elevation forests is changing: The sub-boreal Scots pine (Pinus sylvestris L.) dominating the dry forests is showing high mortality rates. Concurrently the sub-Mediterranean pubescent oak (Quercus pubescens Willd.) has locally increased in abundance. However, it remains unclear whether this local change in species composition is part of a larger-scale vegetation shift. To study variability in mortality and regeneration in these dry forests we analysed data from the Swiss national forest inventory (NFI) on a regular grid between 1983 and 2003, and combined it with annual mortality data from a monitoring site. Pine mortality was found to be highest at low elevation (below 1000 m a.s.l.). Annual variation in pine mortality was correlated with a drought index computed for the summer months prior to observed tree death. A generalized linear mixed-effects model indicated for the NFI data increased pine mortality on dryer sites with high stand competition, particularly for small-diameter trees. Pine regeneration was low in comparison to its occurrence in the overstorey, whereas oak regeneration was comparably abundant. Although both species regenerated well at dry sites, pine regeneration was favoured at cooler sites at higher altitude and oak regeneration was more frequent at warmer sites, indicating a higher adaptation potential of oaks under future warming. Our results thus suggest that an extended shift in species composition is actually occurring in the pine forests in the Valais. The main driving factors are found to be climatic variability, particularly drought, and variability in stand structure and topography. Thus, pine forests at low elevations are developing into oak forests with unknown consequences for these ecosystems and their goods and services.}, language = {en} } @inproceedings{KoetterDeckerDetzleretal.2012, author = {K{\"o}tter, Jens and Decker, Stefan and Detzler, Raphael and Sch{\"a}fer, Jochen and Schmitz, Mark and Herrmann, Ulf}, title = {Cost Reduction of Solar Fields with HelioTrough Collector}, publisher = {FLAGSOL}, address = {K{\"o}ln}, pages = {9 S. : Ill., graph. Darst.}, year = {2012}, language = {en} } @incollection{NiendorfWinterFrauenrath2012, author = {Niendorf, Thoralf and Winter, Lukas and Frauenrath, Tobias}, title = {Electrocardiogram in an MRI environment: Clinical needs, practical considerations, safety implications, technical solutions and fFuture directions}, series = {Advances in Electrocardiograms - Methods and Analysis}, booktitle = {Advances in Electrocardiograms - Methods and Analysis}, editor = {Millis, Richard}, publisher = {IntechOpen}, address = {London}, isbn = {978-953-307-923-3 (print)}, doi = {10.5772/24340}, pages = {309 -- 324}, year = {2012}, language = {en} } @article{AbouzarPoghossianCherstvyetal.2012, author = {Abouzar, Maryam H. and Poghossian, Arshak and Cherstvy, Andrey G. and Pedraza, Angela M. and Ingebrandt, Sven and Sch{\"o}ning, Michael Josef}, title = {Label-free electrical detection of DNA by means of field-effect nanoplate capacitors: Experiments and modeling}, series = {Physica Status Solidi (a)}, volume = {209}, journal = {Physica Status Solidi (a)}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201100710}, pages = {925 -- 934}, year = {2012}, abstract = {Label-free electrical detection of consecutive deoxyribonucleic acid (DNA) hybridization/denaturation by means of an array of individually addressable field-effect-based nanoplate silicon-on-insulator (SOI) capacitors modified with gold nanoparticles (Au-NP) is investigated. The proposed device detects charge changes on Au-NP/DNA hybrids induced by the hybridization or denaturation event. DNA hybridization was performed in a high ionic-strength solution to provide a high hybridization efficiency. On the other hand, to reduce the screening of the DNA charge by counter ions and to achieve a high sensitivity, the sensor signal induced by the hybridization and denaturation events was measured in a low ionic-strength solution. High sensor signals of about 120, 90, and 80 mV were registered after the DNA hybridization, denaturation, and re-hybridization events, respectively. Fluorescence microscopy has been applied as reference method to verify the DNA immobilization, hybridization, and denaturation processes. An electrostatic charge-plane model for potential changes at the gate surface of a nanoplate field-effect sensor induced by the DNA hybridization has been developed taking into account both the Debye length and the distance of the DNA charge from the gate surface.}, language = {en} } @inproceedings{NixFrotscherStaat2012, author = {Nix, Yvonne and Frotscher, Ralf and Staat, Manfred}, title = {Implementation of the edge-based smoothed extended finite element method}, series = {Proceedings 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012}, booktitle = {Proceedings 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012}, editor = {Eberhardsteiner, J.}, year = {2012}, language = {en} } @inproceedings{SchoppNachtrodtHeuermannetal.2012, author = {Schopp, Christoph and Nachtrodt, Frederik and Heuermann, Holger and Scherer, Ulrich W. and Mostacci, Domiziano and Finger, Torsten and Tietsch, Wolfgang}, title = {A novel 2.45 GHz/200 W Microwave Plasma Jet for High Temperature Applications above 3600 K}, series = {Journal of Physics : Conference Series}, volume = {406}, booktitle = {Journal of Physics : Conference Series}, number = {012029}, issn = {1742-6596}, pages = {5}, year = {2012}, language = {en} } @inproceedings{PhamNguyenStaat2012, author = {Pham, Phu Tinh and Nguyen, Thanh Ngoc and Staat, Manfred}, title = {FEM based shakedown analysis of hardening structures}, series = {Proceedings International Conference on Advances in Computational Mechanics (ACOME)}, booktitle = {Proceedings International Conference on Advances in Computational Mechanics (ACOME)}, pages = {870 -- 882}, year = {2012}, language = {en} } @article{Staat2012, author = {Staat, Manfred}, title = {Limit and shakedown analysis under uncertainty}, series = {Tap chi Khoa hoc \& ung dung - Dai hoc Ton Duc Thang}, volume = {19}, journal = {Tap chi Khoa hoc \& ung dung - Dai hoc Ton Duc Thang}, pages = {45 -- 47}, year = {2012}, language = {en} } @article{HuckPoghossianWagneretal.2012, author = {Huck, Christina and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Combined amperometric/field-effect sensor for the detection of dissolved hydrogen}, series = {Sensors and actuators B: Chemical}, volume = {187}, journal = {Sensors and actuators B: Chemical}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0925-4005}, doi = {10.1016/j.snb.2012.10.050}, pages = {168 -- 173}, year = {2012}, abstract = {Real-time and reliable monitoring of the biogas process is crucial for a stable and efficient operation of biogas production in order to avoid digester breakdowns. The concentration of dissolved hydrogen (H₂) represents one of the key parameters for biogas process control. In this work, a one-chip integrated combined amperometric/field-effect sensor for monitoring the dissolved H₂ concentration has been developed for biogas applications. The combination of two different transducer principles might allow a more accurate and reliable measurement of dissolved H₂ as an early warning indicator of digester failures. The feasibility of the approach has been demonstrated by simultaneous amperometric/field-effect measurements of dissolved H₂ concentrations in electrolyte solutions. Both, the amperometric and the field-effect transducer show a linear response behaviour in the H₂ concentration range from 0.1 to 3\% (v/v) with a slope of 198.4 ± 13.7 nA/\% (v/v) and 14.9 ± 0.5 mV/\% (v/v), respectively.}, language = {en} } @inproceedings{PoghossianAbouzarSchoening2012, author = {Poghossian, Arshak and Abouzar, Maryam H. and Sch{\"o}ning, Michael Josef}, title = {(Bio-­)chemical sensor array based on nanoplate SOI capacitors}, series = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012}, booktitle = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012}, editor = {Abdelghani, Adnane and Sch{\"o}ning, Michael Josef}, pages = {31 -- 31}, year = {2012}, language = {en} } @inproceedings{SchusserLeinhosPoghossianetal.2012, author = {Schusser, Sebastian and Leinhos, Marcel and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Biopolymer-degradation monitoring by chip-­based impedance spectroscopy technique}, series = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012}, booktitle = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012}, editor = {Abdelghani, Adnane and Sch{\"o}ning, Michael Josef}, pages = {47 -- 47}, year = {2012}, language = {en} } @book{DigelZhubanovaAkimbekov2012, author = {Digel, Ilya and Zhubanova, Azhar Ahmetovna and Akimbekov, Nuraly S.}, title = {Visual Virology}, address = {Almaty}, isbn = {978-601-247-298-1}, pages = {144 S. : zahlr. Ill.}, year = {2012}, language = {en} } @inproceedings{FrotscherRaatschenStaat2012, author = {Frotscher, Ralf and Raatschen, Hans-J{\"u}rgen and Staat, Manfred}, title = {Application of an edge-based smoothed finite element method on geometrically non-linear plates of non-linear material}, series = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)}, booktitle = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)}, editor = {Eberhardsteiner, J.}, year = {2012}, language = {en} } @inproceedings{AlexopoulosHoffschmidtRauetal.2012, author = {Alexopoulos, Spiros and Hoffschmidt, Bernhard and Rau, Christoph and Sattler, Johannes Christoph}, title = {Simulation of hybrid solar tower power plants}, series = {30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, booktitle = {30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, publisher = {Curran}, address = {Red Hook, NY}, organization = {International Solar Energy Society}, pages = {4044 -- 4050}, year = {2012}, language = {en} } @article{StaatVu2012, author = {Staat, Manfred and Vu, Duc Khoi}, title = {Limit analysis of flaws in pressurized pipes and cylindrical vessels Part II: Circumferential defects}, series = {Engineering Fracture Mechanics ; 97(2013), H. 1}, volume = {97}, journal = {Engineering Fracture Mechanics ; 97(2013), H. 1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0013-7944}, doi = {10.1016/j.engfracmech.2012.05.017}, pages = {314 -- 333}, year = {2012}, abstract = {Upper and lower bound theorems of limit analyses have been presented in part I of the paper. Part II starts with the finite element discretization of these theorems and demonstrates how both can be combined in a primal-dual optimization problem. This recently proposed numerical method is used to guide the development of a new class of closed-form limit loads for circumferential defects, which show that only large defects contribute to plastic collapse with a rapid loss of strength with increasing crack sizes. The formulae are compared with primal-dual FEM limit analyses and with burst tests. Even closer predictions are obtained with iterative limit load solutions for the von Mises yield function and for the Tresca yield function. Pressure loading of the faces of interior cracks in thick pipes reduces the collapse load of circumferential defects more than for axial flaws. Axial defects have been treated in part I of the paper.}, language = {en} } @article{GrandeMeffertSchoenbergeretal.2012, author = {Grande, Marion and Meffert, Elisabeth and Schoenberger, Eva and Jung, Stefanie and Frauenrath, Tobias and Huber, Walter and Hussmann, Katja and Moormann, Mareike and Heim, Stefan}, title = {From a concept to a word in a syntactically complete sentence: An fMRI study on spontaneous language production in an overt picture description task}, series = {NeuroImage}, volume = {61}, journal = {NeuroImage}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1522-2586}, doi = {10.1016/j.neuroimage.2012.03.087}, pages = {702 -- 714}, year = {2012}, abstract = {Spontaneous language has rarely been subjected to neuroimaging studies. This study therefore introduces a newly developed method for the analysis of linguistic phenomena observed in continuous language production during fMRI. Most neuroimaging studies investigating language have so far focussed on single word or — to a smaller extent — sentence processing, mostly due to methodological considerations. Natural language production, however, is far more than the mere combination of words to larger units. Therefore, the present study aimed at relating brain activation to linguistic phenomena like word-finding difficulties or syntactic completeness in a continuous language fMRI paradigm. A picture description task with special constraints was used to provoke hesitation phenomena and speech errors. The transcribed speech sample was segmented into events of one second and each event was assigned to one category of a complex schema especially developed for this purpose. The main results were: conceptual planning engages bilateral activation of the precuneus. Successful lexical retrieval is accompanied - particularly in comparison to unsolved word-finding difficulties - by the left middle and superior temporal gyrus. Syntactic completeness is reflected in activation of the left inferior frontal gyrus (IFG) (area 44). In sum, the method has proven to be useful for investigating the neural correlates of lexical and syntactic phenomena in an overt picture description task. This opens up new prospects for the analysis of spontaneous language production during fMRI.}, language = {en} } @inproceedings{HartmannKallweitFeldusenetal.2012, author = {Hartmann, Axel and Kallweit, Stephan and Feldusen, Antje and Schr{\"o}der, Wolfgang}, title = {Detection of upstream propagating sound waves at buffet flow using high-speed PIV}, pages = {14 S. : graph. Darst.}, year = {2012}, language = {en} } @misc{FrauenrathPfeifferHezeletal.2012, author = {Frauenrath, Tobias and Pfeiffer, Harald and Hezel, Fabian and Dieringer, Matthias A. and Winter, Lukas and Gr{\"a}ßl, Andreas and Santoro, Davide and {\"O}zerdem, Celal and Renz, Wolfgang and Greiser, Andreas and Niendorf, Thoralf}, title = {Lessons learned from cardiac MRI at 7.0 T: LV function assessment at 3.0 T using local multi-channel transceiver coil arrays}, series = {2012 ISMRM Annual Meeting Proceedings}, journal = {2012 ISMRM Annual Meeting Proceedings}, issn = {1545-4428}, year = {2012}, abstract = {Cardiac MR (CMR) is of proven clinical value but also an area of vigorous ongoing research since image quality is not always exclusively defined by signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Recent developments of CMR at 7.0 T have been driven by pioneering explorations into novel multichannel transmit and receive coil array technology to tackle the challenges B1+-field inhomogeneities, to offset specific-absorption rate (SAR) constraints and to reduce banding artifacts in SSFP imaging. For this study, recognition of the benefits and performance of local surface Tx/Rx-array structures recently established at 7.0 T inspired migration to 3.0 T, where RF inhomogeneities and SAR limitations encountered in routine clinical CMR, though somewhat reduced versus the 7.0 T situation, remain significant. For all these reasons, this study was designed to build and examine the feasibility of a local four channel Tx/Rx cardiac coil array for anatomical and functional cardiac imaging at 3.0 T. For comparison, a homebuilt 4 channel Rx cardiac coil array exhibiting the same geometry as the Tx/Rx coil and a Rx surface coil array were used.}, language = {en} } @inproceedings{FerreinKallweitLautermann2012, author = {Ferrein, Alexander and Kallweit, Stephan and Lautermann, Mark}, title = {Towards an autonomous pilot system for a tunnel boring machine}, series = {5th Robotics and Mechatronics Conference of South Africa (ROBMECH) : 26 - 27 November 2012 ; CSIR International Conference Centre Gauteng South Africa}, booktitle = {5th Robotics and Mechatronics Conference of South Africa (ROBMECH) : 26 - 27 November 2012 ; CSIR International Conference Centre Gauteng South Africa}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-5183-6}, year = {2012}, language = {en} } @inproceedings{FuchsRitzStrauch2012, author = {Fuchs, Britta and Ritz, Thomas and Strauch, Jakob}, title = {Usability of mobile applications : dissemination of usability engineering in small and medium enterprises}, series = {Proceedings of the International Conference on Data Communication Networking, e-Business and Optical Communication Systems : Rome, Italy, 24 - 27 July, 2012 ; [integrated in the ICETE (International Conference on e-Business and Telecommunications)]}, booktitle = {Proceedings of the International Conference on Data Communication Networking, e-Business and Optical Communication Systems : Rome, Italy, 24 - 27 July, 2012 ; [integrated in the ICETE (International Conference on e-Business and Telecommunications)]}, editor = {Obaidat, Mohammad S.}, publisher = {SciTePress}, address = {[Lissabon]}, isbn = {978-989-8565-23-5}, pages = {272 -- 277}, year = {2012}, language = {en} }