Homotopy Lie Superalgebra in Yang-Mills Theory

The Yang-Mills equations are formulated in the form of generalized Maurer-Cartan equations, such that the corresponding algebraic operations are shown to satisfy the defining relations of homotopy Lie superalgebra.Comment: LaTeX2e, 10 page

A quality integrated spectral minutiae fingerprint recognition system

Many fingerprint recognition systems are based on minutiae matching. However, the recognition accuracy of minutiae-based matching algorithms is highly dependent on the fingerprint minutiae quality. Therefore, in this paper, we introduce a quality integrated spectral minutiae algorithm, in which the minutiae quality information is incorporated to enhance the performance of the spectral minutiae fingerprint recognition system. In our algorithm, two types of quality data are used. The first is the minutiae reliability, expressing the probability that a given point is indeed a minutia; the second is the minutiae location accuracy, quantifying the error on the minutiae location. We integrate these two types of quality information into the spectral minutiae representation algorithm and achieve a decrease of 1% in equal error rate in the experiment

Spectral representation of fingerprints

Most fingerprint recognition systems are based on the use of a minutiae set, which is an unordered collection of minutiae locations and directions suffering from various deformations such as translation, rotation and scaling. The spectral minutiae representation introduced in this paper is a novel method to represent a minutiae set as a fixed-length feature vector, which is invariant to translation, and in which rotation and scaling become translations, so that they can be easily compensated for. These characteristics enable the combination of fingerprint recognition systems with a template protection scheme, which requires a fixed-length feature vector. This paper introduces the idea and algorithm of spectral minutiae representation. A correlation based spectral minutiae\ud matching algorithm is presented and evaluated. The scheme shows a promising result, with an equal error rate of 0.2% on manually extracted minutiae

Theoretische Informatica

Deze notitie beschrijft in het kort wat theoretische informatica is en hoe dit door de groep Theoretische Invormatica van de Universiteit Twente wordt bedreven in onderwijs en onderzoek

Hydrogen bonding and charge transport in a protic polymerized ionic liquid

Hydrogen bonding and charge transport in the protic polymerized ionic liquid poly[tris(2-(2-methoxyethoxy)ethyl)ammoniumacryloxypropyl sulfonate] (PAAPS) are studied by combining Fourier transform infrared (FTIR) and broadband dielectric spectroscopy (BDS) in a wide temperature range from 170 to 300 K. While the former enables to determine precisely the formation of hydrogen bonds and other moiety-specific quantized vibrational states, the latter allows for recording the complex conductivity in a spectral range from 10−2 to 10+9  Hz. A pronounced thermal hysteresis is observed for the H-bond network formation in distinct contrast to the reversibility of the effective conductivity measured by BDS. On the basis of this finding and the fact that the conductivity changes with temperature by orders of magnitude, whereas the integrated absorbance of the N–H stretching vibration (being proportional to the number density of protons in the hydrogen bond network) changes only by a factor of 4, it is concluded that charge transport takes place predominantly due to hopping conduction assisted by glassy dynamics (dynamic glass transition assisted hopping) and is not significantly affected by the establishment of H-bonds

Fingerprints of homogeneous nucleation and crystal growth in polyamide 66 as studied by combined infrared spectroscopy and fast scanning chip calorimetry

Homogenous crystal nucleation and growth in polyamide 66 (PA66) are followed in situ by means of a combination of FTIR spectroscopy and fast scanning chip calorimetry (FSC). Therefore, a novel setup with a calorimetry chip equipped with an IR-transparent SiN membrane was developed, which enables to examine IR spectroscopic and FSC experiments on the identical specimen. Because of the small amount of sample material (~ 100 ng), it is possible to achieve heating and cooling rates up to 5000 Ks−1, and hence to quench the sample into a fully amorphous state without quenched-in homogeneous crystal nuclei. Annealing the film then allows to determine the onset of homogenous nucleation and crystal growth by means of FSC, whereas molecular interactions are unraveled by FTIR spectroscopy. It is demonstrated that different moieties of PA66 respond distinctly during crystallization; far-reaching interactions such as hydrogen bonding are established prior to onset of short-range steric hindrance

In-field entanglement distribution over a 96 km-long submarine optical fibre

Techniques for the distribution of quantum-secured cryptographic keys have reached a level of maturity allowing them to be implemented in all kinds of environments, away from any form of laboratory infrastructure. Here, we detail the distribution of entanglement between Malta and Sicily over a 96 km-long submarine telecommunications optical fibre cable. We used this standard telecommunications fibre as a quantum channel to distribute polarisation-entangled photons and were able to observe around 257 photon pairs per second, with a polarisation visibility above 90%. Our experiment demonstrates the feasibility of using deployed submarine telecommunications optical fibres as long-distance quantum channels for polarisation-entangled photons. This opens up a plethora of possibilities for future experiments and technological applications using existing infrastructure.Comment: 6 pages, 4 figure

Kite-Powered Design-to-Robotic-Production for Affordable Building on Demand

<p>Building technologies employed today in 2nd and 3rd world countries are imported, expensive, outdated and unsustainable. Highly developed countries, on the other hand, rapidly advance in developing affordable, numerically controlled and robotically supported material- and energy-efficient methods for building on demand. The research team proposes to close this gap by applying advanced design-to-robotic-production (D2RP) technologies developed at Technical University Delft (TUD) to construction problems in 2nd and 3rd world countries. The provided tool base uses refurbished robotic technology, which is retrofitted with state-ofthe-art open source control software, and by employing local approaches and available materials the dependency on imported materials and processes is drastically reduced. The D2RP unit is coupled with the electricity generating Kite Power (KP) system developed at TUD to create a mobile sustainable autarkic unit that can be deployed everywhere.</p

Association of Altered Plasma Lipidome with Disease Severity in COVID-19 Patients

The severity of COVID-19 is linked to an imbalanced immune response. The dysregulated metabolism of small molecules and bioactive lipids has also been associated with disease severity. To promote understanding of the disease biochemistry and provide targets for intervention, we applied a range of LC-MS platforms to analyze over 100 plasma samples from patients with varying COVID-19 severity and with detailed clinical information on inflammatory responses (&gt;30 immune markers). This is the third publication in a series, and it reports the results of comprehensive lipidome profiling using targeted LC-MS/MS. We identified 1076 lipid features across 25 subclasses, including glycerophospholipids, sterols, glycerolipids, and sphingolipids, among which 531 lipid features were dramatically changed in the plasma of intensive care unit (ICU) patients compared to patients in the ward. Patients in the ICU showed 1.3–57-fold increases in ceramides, (lyso-)glycerophospholipids, diglycerides, triglycerides, and plasmagen phosphoethanolamines, and 1.3–2-fold lower levels of a cyclic lysophosphatidic acid, sphingosine-1-phosphates, sphingomyelins, arachidonic acid-containing phospholipids, lactosylceramide, and cholesterol esters compared to patients in the ward. Specifically, phosphatidylinositols (PIs) showed strong fatty acid saturation-dependent behavior, with saturated fatty acid (SFA)- and monosaturated fatty acid (MUFA)-derived PI decreasing and polystaturated (PUFA)-derived PI increasing. We also found ~4000 significant Spearman correlations between lipids and multiple clinical markers of immune response with |R| ≥ 0.35 and FDR corrected Q &lt; 0.05. Except for lysophosphatidic acid, lysophospholipids were positively associated with the CD4 fraction of T cells, and the cytokines IL-8 and IL-18. In contrast, sphingosine-1-phosphates were negatively correlated with innate immune markers such as CRP and IL-6. Further indications of metabolic changes in moderate COVID-19 disease were demonstrated in recovering ward patients compared to those at the start of hospitalization, where 99 lipid species were altered (6 increased by 30–62%; 93 decreased by 1.3–2.8-fold). Overall, these findings support and expand on early reports that dysregulated lipid metabolism is involved in COVID-19.</p