TY  - CHAP
A1  - Burgeth, Bernhard
A1  - Kleefeld, Andreas
A1  - Zhang, Eugene
A1  - Zhang, Yue
ED  - Baudrier, Étienne
ED  - Naegel, Benoît
ED  - Krähenbühl, Adrien
ED  - Tajine, Mohamed
T1  - Towards Topological Analysis of Non-symmetric Tensor Fields via Complexification
T2  - Discrete Geometry and Mathematical Morphology
N2  - Fields of asymmetric tensors play an important role in many applications such as medical imaging (diffusion tensor magnetic resonance imaging), physics, and civil engineering (for example Cauchy-Green-deformation tensor, strain tensor with local rotations, etc.). However, such asymmetric tensors are usually symmetrized and then further processed. Using this procedure results in a loss of information. A new method for the processing of asymmetric tensor fields is proposed restricting our attention to tensors of second-order given by a 2x2 array or matrix with real entries. This is achieved by a transformation resulting in Hermitian matrices that have an eigendecomposition similar to symmetric matrices. With this new idea numerical results for real-world data arising from a deformation of an object by external forces are given. It is shown that the asymmetric part indeed contains valuable information.
Y1  - 2022
SN  - 978-3-031-19897-7
U6  - https://doi.org/10.1007/978-3-031-19897-7_5
N1  - Second International Joint Conference, DGMM 2022, Strasbourg, France, October 24–27, 2022
N1  - Corresponding author: Andreas Kleefeld
SP  - 48
EP  - 59
PB  - Springer
CY  - Cham
ER  - 
TY  - GEN
A1  - Burgeth, Bernhard
A1  - Kleefeld, Andreas
A1  - Naegel, Benoît
A1  - Perret, Benjamin
T1  - Editorial — Special Issue: ISMM 2019
T2  - Mathematical Morphology - Theory and Applications
N2  - This editorial presents the Special Issue dedicated to the conference ISMM 2019 and summarizes the articles published in this Special Issue.
Y1  - 2020
U6  - https://doi.org/10.1515/mathm-2020-0200
SN  - 2353-3390
VL  - 4
IS  - 1
SP  - 159
EP  - 161
PB  - De Gruyter
CY  - Warschau
ER  - 
TY  - CHAP
A1  - Burger, Ulrich
A1  - Kirsch, Ansgar
A1  - Marcher, Thomas
A1  - Höser, Sebastian
T1  - Geologisch-geotechnischer Planungsprozess von Tunnelbauten mit Schwerpunkt tiefliegender Tunnel
T2  - Beton-Kalender ; Bd. 103: Unterirdisches Bauen, Grundbau, Eurocode 7
Y1  - 2014
SN  - 978-3-433-03051-6 ; 978-3-433-60335-2 ; 978-3-433-60508-0 ; 3-433-60508-4
SP  - 37
EP  - 62
PB  - Ernst
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Burger, René
A1  - Rumpf, Jessica
A1  - Do, Xuan Tung
A1  - Monakhova, Yulia
A1  - Diehl, Bernd W. K.
A1  - Rehahn, Matthias
A1  - Schulze, Margit
T1  - Is NMR combined with multivariate regression applicable for the molecular weight determination of randomly cross-linked polymers such as lignin?
JF  - ACS Omega
N2  - The molecular weight properties of lignins are one of the key elements that need to be analyzed for a successful industrial application of these promising biopolymers. In this study, the use of 1H NMR as well as diffusion-ordered spectroscopy (DOSY NMR), combined with multivariate regression methods, was investigated for the determination of the molecular weight (Mw and Mn) and the polydispersity of organosolv lignins (n = 53, Miscanthus x giganteus, Paulownia tomentosa, and Silphium perfoliatum). The suitability of the models was demonstrated by cross validation (CV) as well as by an independent validation set of samples from different biomass origins (beech wood and wheat straw). CV errors of ca. 7–9 and 14–16% were achieved for all parameters with the models from the 1H NMR spectra and the DOSY NMR data, respectively. The prediction errors for the validation samples were in a similar range for the partial least squares model from the 1H NMR data and for a multiple linear regression using the DOSY NMR data. The results indicate the usefulness of NMR measurements combined with multivariate regression methods as a potential alternative to more time-consuming methods such as gel permeation chromatography.
Y1  - 2021
U6  - https://doi.org/10.1021/acsomega.1c03574
SN  - 2470-1343
VL  - 6
IS  - 44
SP  - 29516
EP  - 29524
PB  - ACS Publications
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Burger, René
A1  - Lindner, Simon
A1  - Rumpf, Jessica
A1  - Do, Xuan Tung
A1  - Diehl, Bernd W.K.
A1  - Rehahn, Matthias
A1  - Monakhova, Yulia
A1  - Schulze, Margit
T1  - Benchtop versus high field NMR: Comparable performance found for the molecular weight determination of lignin
JF  - Journal of Pharmaceutical and Biomedical Analysis
N2  - Lignin is a promising renewable biopolymer being investigated worldwide as an environmentally benign substitute of fossil-based aromatic compounds, e.g. for the use as an excipient with antioxidant and antimicrobial properties in drug delivery or even as active compound. For its successful implementation into process streams, a quick, easy, and reliable method is needed for its molecular weight determination. Here we present a method using 1H spectra of benchtop as well as conventional NMR systems in combination with multivariate data analysis, to determine lignin’s molecular weight (Mw and Mn) and polydispersity index (PDI). A set of 36 organosolv lignin samples (from Miscanthus x giganteus, Paulownia tomentosa and Silphium perfoliatum) was used for the calibration and cross validation, and 17 samples were used as external validation set. Validation errors between 5.6% and 12.9% were achieved for all parameters on all NMR devices (43, 60, 500 and 600 MHz). Surprisingly, no significant difference in the performance of the benchtop and high-field devices was found. This facilitates the application of this method for determining lignin’s molecular weight in an industrial environment because of the low maintenance expenditure, small footprint, ruggedness, and low cost of permanent magnet benchtop NMR systems.
KW  - NMR
KW  - PLS-regression
KW  - Molecular weight determination
KW  - Chemometrics
KW  - Biomass
Y1  - 2022
SN  - 0731-7085
U6  - https://doi.org/10.1016/j.jpba.2022.114649
VL  - 212
IS  - Article number: 114649
PB  - Elsevier
CY  - New York, NY
ER  - 
TY  - CHAP
A1  - Burgazzi, L.
A1  - Fiorini, F.
A1  - De Magistris, W. (u.a.)
A1  - Lensa, W. von
A1  - Staat, Manfred
A1  - Altes, J.
T1  - Reliability Assessment of Passive Safety Systems
T2  - Proceedings of the 6th International Conference on Nuclear Engineering : ICONE : May 10 - 14, 1998, San Diego, Calif.
Y1  - 1998
N1  - CD-ROM
PB  - American Society of Mechanical Engineers
CY  - New York
ER  - 
TY  - JOUR
A1  - Buniatyan, Vahe V.
A1  - Matirosyan, N.
A1  - Abouzar, Maryam H.
A1  - Schubert, J.
A1  - Zander, W.
A1  - Gevorgian, S.
A1  - Schöning, Michael Josef
A1  - Poghossian, Arshak
T1  - Capacitive field-effect pH sensor based on an electrolyte-ferroelectric-insulator-semiconductor structure
JF  - SENSOR 2009 : : 14th International Conference on Sensors, Technologies, Electronics and Applications; Nürnberg, Germany, 26 - 28 May 2009; proceedings; [part of] Sensor + Test Conference 2009 / AMA, Fachverband für Sensorik e.V
Y1  - 2009
SN  - 9783981099355
N1  - AMA, Fachverband für Sensorik ; Sensor International Conference ; (14 : ; 2009.05.26-28 : ; Nürnberg)
SP  - 317
EP  - 322
PB  - AMA Service
CY  - Wunstorf
ER  - 
TY  - JOUR
A1  - Buniatyan, Vahe V.
A1  - Abouzar, Maryam H.
A1  - Martirosyan, Norayr W.
A1  - Schubert, Jürgen
A1  - Gevorgian, Spartak
A1  - Schöning, Michael Josef
A1  - Poghossian, Arshak
T1  - pH-sensitive properties of barium strontium titanate (BST) thin films prepared by pulsed laser deposition technique
JF  - Physica Status Solidi (A). 207 (2010), H. 4
Y1  - 2010
SN  - 1862-6300
N1  - Special Issue: Engineering of Functional Interfaces EnFI 2009
SP  - 824
EP  - 830
ER  - 
TY  - JOUR
A1  - Buniatyan, V. V.
A1  - Matirosyan, N. W.
A1  - Abouzar, Maryam H.
A1  - Schöning, Michael Josef
A1  - Poghossian, Arshak
A1  - Schubert, J.
A1  - Khachatryan, V. R.
A1  - Soukiassyan, G. R.
T1  - (Ba,Sr)TiO3 based electrolyte-insulator-semiconductor pHsensors: comparitive study
JF  - Semiconductor micro- and nanoelectronics : Proceedings of the Seventh International Conference , Tsakhcadzor, Armenia July 3-5 2009
Y1  - 2009
SP  - 71
EP  - 74
ER  - 
TY  - CHAP
A1  - Buniatyan, V. V.
A1  - Huck, Christina
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
A1  - Rustamyan, L. G.
A1  - Hovnikyan, H. H.
T1  - Equivalent circuit and optimization of impedance characteristics of an electrolyte conductivity sensor
T2  - Proceedings of State Engineering University Armenia : Series Information technologies, electronics, radio engineering
Y1  - 2014
VL  - Iss. 17
IS  - No. 1
SP  - 69
EP  - 76
ER  -