cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Investigation on inkjet printing for electromagnetic compatibility application
Creators: name: Hartwig, Melinda
name: Polomoshnov, Maxim
name: Zichner, Ralf
name: Baumann, Reinhard R.
Publisher: name: Technologies for Lightweight Structures (TLS)
Year: 2018

description: The research is focused on the development of inkjet-printed silver grids on flexible films to (I) attenuate electromagnetic waves at 2.45 GHz locally by applying them directly on Wi-Fi or Bluetooth transmitter or to (II) protect electromagnetic compatibility (EMC) sensitive devices close to electromagnetic transmitters. The inkjet printing technology leads to resource, time as well as cost efficient manufacturing and simplifies the adjustment of the pattern design regarding different applications. The research contains a fundamental analysis of the behavior of printed silver patterns on flexible polymer substrates regarding line widths, layer morphology and electrical performance. On that basis the grid pattern for a certain frequency range is simulated. The report shows first simulation results on basis of the given material parameters. The results are the fundamentals for further research on realization of the simulated grid patterns by inkjet printing technology.
description: Technologies for Lightweight Structures (TLS), Vol 1, No 2 (2017): Special Issue: 3rd International MERGE Technologies Conference (IMTC), 21st - 22nd September 2017, Chemnitz
Dynamical properties of a large young disk galaxy at z=2.03
Creators: name: van Starkenburg, L.
name: van der Werf, P. P.
name: Franx, M.
name: Labbe, I.
name: Rudnick, G.
name: Wuyts, S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Context. The study of high redshift Tully-Fisher relations (TFRs) is limited by the use of long slit spectrographs, rest frame B band and star formation selected galaxies. Aims. We try to circumvent these issues by using integral field spectroscopy (SINFONI), by studying the rest frame K band and stellar mass TFR, and by selecting targets without a bias to strongly star forming galaxies. In this paper, we demonstrate our methods on our best case. This galaxy, F257, at z=2.03, was selecte from a sample of candidate high redshift large disk galaxies in the Hubble Deep Field South that were selected with photometric and morphological criteria. Methods. We used SINFONI at the VLT to obtain an integral field spectrum of the Halpha line and hence a velocity field and rotation curve. We also use UBVIJHK+IRAC band photometry to determine a stellar photometric mass. Results. We find that F257 is indistinguishable from local late type galaxies in many respects: it has a regular velocity field, increasing velocity disperion towards its center, its rotation curve flattens at 1-2 disk scale lengths, it has the same specific angular momentum as local disks, its properties are consistent with the local K band TFR. Although mainly rotationally supported, its gas component is dynamically heated with respect to local galaxies (V/sigma_z ~ 4) and it is offset from the local stellar mass TFR at the 2sigma level. But, this offset depends on the SED modeling parameters. In particular, for a 2-component star formation history (SFH), F257 is in agreement with the local stellar mass TFR. F257 is then a nearly (~75%) maximum disk. The dynamical properties of F257 are more like those of local galaxies than those of any other galaxy at similar redshift observed to date. However, the gas-to-stellar mass ratio is unusally large: 2.5.
description: Accepted for publication in A&A, 15 pages, 14 figures
Microstructuring of joining areas in aluminum alloy sheets by Jet Electrochemical Machining
Creators: name: Schimmelpfennig, Rene
Publisher: name: Technologies for Lightweight Structures (TLS)
Year: 2018

description: In this work the increase of the tensile shear strength by means of microstructuring of the metallic part for ultrasonic vibration assisted joining of hybrid compounds is presented. The aluminum alloy EN AW-5083 and a carbon fibre-reinforced plastic (CFRP) from Bond Laminates are used as a material combination. A suitable method is electrochemical processing (ECM). The microstructuring is carried out with continuous electrolyte free jet machining (Jet-ECM): Characteristic of this technology is the restriction of the electric current to a limited area of the electrolyte jet. After describing the materials and sample geometry used, the Jet-ECM technology and the ultrasonic vibration assisted joining process are explained. The strength of the joint is assessed by means of a tensile shear test. The determined results of the tensile shear strength for hybrid connections between microstructured aluminum sheets and CFRP are compared with those of unstructured aluminum sheets. Furthermore, the influence of the microstructure on the tensile shear strength achieved is discussed using metallographic cross-sections of the joining area.
description: Technologies for Lightweight Structures (TLS), Vol 1, No 2 (2017): Special Issue: 3rd International MERGE Technologies Conference (IMTC), 21st - 22nd September 2017, Chemnitz
Influence of the cooling behaviour on mechanical properties of carbon fibre-reinforced thermoplastic/metal laminates
Creators: name: Zopp, Camilo
name: Nestler, Daisy
name: Buschner, Nadine
name: Mende, Carola
name: Mauersberger, Sven
name: Tröltzsch, Jürgen
name: Nendel, Sebastian
name: Nendel, Wolfgang
name: Kroll, Lothar
name: Gehde, Michael
Publisher: name: Technologies for Lightweight Structures (TLS)
Year: 2018

description: For several years, thermoplastic hybrid laminates form a new class in the field of material compounds. These laminates consist of fibre-reinforced plastic prepregs and metal layers in alternating order. Compared to conventional thermosetting multilayer composites, these laminates are suitable for large-scale production and can be manufactured with significantly reduced cycle times in the thermoforming process.

In the framework of this contribution, the influence of the cooling rate of carbon fibre-reinforced thermoplastic composites and hybrid laminates was investigated with regard to crystallinity and the resulting mechanical properties. Polyamide 6 and thermoplastic polyurethane as matrix systems were examined, in particular.
Additionally, the differential scanning calorimetry was used in order to investigate the influence of the cooling rate on the crystallisation behaviour. It could be determined that the cooling rate has a limited influence on the crystallisation of polyamide 6 and this influences the mechanical properties. Furthermore, a reliance of process parameters on the characteristics profile of composite materials and material compounds with thermoplastic polyurethane could be identified. Depending on process conditions, tensile, bending, and interlaminar shear properties fluctuate up to 20 % in fibre-reinforced laminates and up to 32 % in hybrid laminates. Moderate to fast cooling rates result in optimum mechanical characteristics of tensile properties in fibre-plastic-compounds. Fast to very fast cooling rates are advisable for bending and interlaminar shear properties. Highest tensile and bending characteristics are achieved in hybrid laminates by using fast to very fast cooling rates, while interlaminar shear properties tend to be highest in slow to moderate cooling rates.
description: Technologies for Lightweight Structures (TLS), Vol 1, No 2 (2017): Special Issue: 3rd International MERGE Technologies Conference (IMTC), 21st - 22nd September 2017, Chemnitz
Strengthening practical continuous-variable quantum key distribution systems against measurement angular error
Creators: name: Shen, Tao
name: Huang, Yundi
name: Wang, Xiangyu
name: Tian, Huiping
name: Chen, Ziyang
name: Yu, Song
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The optical phase shifter that constantly rotates the local oscillator phase is a necessity in continuous-variable quantum key distribution systems with heterodyne detection. In previous experimental implementations, the optical phase shifter is generally regarded as an ideal passive optical device that perfectly rotates the phase of the electromagnetic wave of $90^\circ$. However, the optical phase shifter in practice introduces imperfections, mainly the measurement angular error, which inevitably deteriorates the security of the practical systems. Here, we will give a concrete interpretation of measurement angular error in practical systems and the corresponding entanglement-based description. Subsequently, from the parameter estimation, we deduce the overestimated excess noise and the underestimated transmittance, which lead to a reduction in the final secret key rate. Simultaneously, we propose an estimation method of the measurement angular error. Next, the practical security analysis is provided in detail, and the effect of the measurement angular error and its corresponding compensation scheme are demonstrated. We conclude that measurement angular error severely degrades the security, but the proposed calibration and compensation method can significantly help improve the performance of the practical CV-QKD systems.
description: 8 pages,6 figures
Technologies for the integration of miniaturised silicon sensor systems in fibre-reinforced composites
Creators: name: Arnold, Benjamin
name: Decker, Ricardo
name: Rost, Florian
name: Bauer, Angelika
name: Mehner, Jan
name: Kroll, Lothar
name: Rzepka, Sven
name: Otto, Thomas
Publisher: name: Technologies for Lightweight Structures (TLS)
Year: 2019

description: Functional integration processes gain more and more importance in lightweight engineering. In this paper we discuss how to improve fibre-reinforced composites with structurally integrated condition monitoring systems, suitable for predicting failure behaviour. Especially commercially available and tested silicon sensors, but also new developments are well-suited for this intention. We present a smart semi-finished textile with integrated silicon sensors for in-situ conditions and process monitoring in fibre-reinforced composites. It consists of a textile substrate tape with integrated electrically conductive fibres and various silicon sensors, applied by micro-injection moulding. A so-called “interposer” is used as an electrical adapter between the microstructures of the sensor system and the mesostructures of the textile. The key technology used for the encapsulation and electrical contacting of the sensor nodes is a two-stage two-component micro injection moulding process, allowing for a cost efficient and application specific mass production. As proof of concept we chose the injection moulding process to investigate the influence of the fabrication process on all electronic components with a silicon stress measurement chip. We performed in-situ measurements of temperature and in-plane mechanical stress for different glass fibre contents of the PA6 melt and tool temperatures and compared the results with a finite element simulation.
description: Technologies for Lightweight Structures (TLS), Vol 1, No 2 (2017): Special Issue: 3rd International MERGE Technologies Conference (IMTC), 21st - 22nd September 2017, Chemnitz
An Information-Theoretic Approach for Automatically Determining the Number of States when Aggregating Markov Chains
Creators: name: Sledge, Isaac J.
name: Principe, Jose C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Theory (cs.IT)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: A fundamental problem when aggregating Markov chains is the specification of the number of state groups. Too few state groups may fail to sufficiently capture the pertinent dynamics of the original, high-order Markov chain. Too many state groups may lead to a non-parsimonious, reduced-order Markov chain whose complexity rivals that of the original. In this paper, we show that an augmented value-of-information-based approach to aggregating Markov chains facilitates the determination of the number of state groups. The optimal state-group count coincides with the case where the complexity of the reduced-order chain is balanced against the mutual dependence between the original- and reduced-order chain dynamics.
description: Submitted to IEEE ICASSP. arXiv admin note: substantial text overlap with arXiv:1903.09266
High-performance machining of fiber-reinforced materials with hybrid ultrasonic-assisted cutting
Creators: name: Stoll, Andrea
name: Rüger, Carlo
name: Busch, Katja
name: Mäder, Thomas
name: Kranz, Burkhard
Publisher: name: Technologies for Lightweight Structures (TLS)
Year: 2018

description: A main approach for sustainable and efficient products is the application of innovative materials like fiber-reinforced plastics. Despite the excellent properties, the machining requirements, especially the hard cutting conditions, restrain the wide application of these materials. Thus a major task is the realization of the required part qualities combined with efficient machining strategies. The project ULTRASPAN, a joint venture of partners from industry and research institutes funded by the BMBF, attends to this challenge. The goal is the development of new hybrid machining concepts and process technologies for enhanced cutting of composite materials with ultrasonic-assistance. Prior condition is the development of novel robust actuators. Therefore, prototypic actuators for longitudinal and torsional vibration systems are developed in the project. Besides the novel actuator concepts, the results of ultrasonic-assisted drilling (UAD) on composite parts are presented in this paper. Machining tests in drilling of fiber-reinforced plastics with the novel prototype actuator systems were performed. Focus of the investigation was the influence of the ultrasonic vibration support on the bore quality. The superimposition of drilling with ultrasonic vibrations influences the process characteristics and engagement of the cutting edge. Machining tests showed the potential to enhance the bore quality with UAD in a certain parameter field.
description: Technologies for Lightweight Structures (TLS), Vol 1, No 2 (2017): Special Issue: 3rd International MERGE Technologies Conference (IMTC), 21st - 22nd September 2017, Chemnitz
Matching gauge theory and string theory in a decoupling limit of AdS/CFT
Creators: name: Harmark, Troels
name: Kristjansson, Kristjan R.
name: Orselli, Marta
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We identify a regime of the AdS/CFT correspondence in which we can quantitatively match N=4 super Yang-Mills (SYM) for small 't Hooft coupling with weakly coupled type IIB string theory on AdS_5 x S^5. We approach this regime by taking the same decoupling limit on both sides of the correspondence. On the gauge theory side only the states in the SU(2) sector survive, and in the planar limit the Hamiltonian is given by the XXX_{1/2} Heisenberg spin chain. On the string theory side we show that the decoupling limit corresponds to a non-relativistic limit. In this limit some of the bosonic modes and all of the fermionic modes of the string become infinitely heavy and decouple. We first take the decoupling limit of the string sigma-model classically. This enables us to identify a semi-classical regime with semi-classical string states even though we are in a regime corresponding to small 't Hooft coupling. We furthermore analyze the quantum corrections that enter in taking the limit. From this we infer that gauge theory and string theory match, both in terms of the action and the spectrum, for the leading part and the first correction away from the semi-classical regime. Finally we consider the implications for the hitherto unexplained matching of the one-loop contribution to the energy of certain gauge theory and string theory states, and we explain how our results give a firm basis for the matching of the Hagedorn temperature in hep-th/0608115.
description: 29 pages, 1 figure. v2: Version published in JHEP, section 4 improved
Laser Beam Melting of Complexly Shaped Honeycomb Structures
Creators: name: Illgner, Matthias
name: Binder, Maximilian
name: Schlick, Georg
name: Seidel, Christian
name: Reinhart, Gunther
Publisher: name: Technologies for Lightweight Structures (TLS)
Year: 2019

description: Laser beam melting (LBM) offers the opportunity to manufacture highly complex structures and geometries and thus provides a big potential to produce lightweight parts. In previous research projects, a software tool has been developed that achieves the placement of hexagonal honeycombs (of any size and wall thickness) on free formed surfaces in a load-oriented manner and thus offers entirely new possibilities for designing lightweight components in CAD (e.g. [1–2]).


This work examines the production of metal hexagonal honeycombs from the material AlSi10Mg with the LBM-process. By adapting the exposure and process parameters, it was possible to manufacture overhanging structures with an overhang angel < 30° (relative to build platform) without support structures, while still achieving an acceptable surface roughness (in the context of this study: Ra = 45 µm). Conventional complex and time consuming post-processing steps can thus be avoided and a higher utilization of building space can be achieved. Furthermore, since the critical size for a lightweight structure is the minimum possible density, it was investigated to which minimum values the wall thicknesses of the hexagonal structures can be reduced using LBM. Apart from that, the stability of the manufactured honeycombs was analyzed in as-built condition and heat treated by pressure test and related to the honeycomb density. This has been used to compare additively manufactured honeycombs with conventionally manufactured ones.
description: Technologies for Lightweight Structures (TLS), Vol 1 No 2 (2017): Special Issue: 3rd International MERGE Technologies Conference (IMTC), 21st - 22nd September 2017, Chemnitz
Transient Optoplasmonic Detection of Single Proteins with Sub-Microsecond Resolution
Creators: name: Baaske, M. D.
name: Asgari, N.
name: Punj, D.
name: Orrit, M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Optoplasmonic methods capable of single protein detection so far rely on analyte immobilization in order to facilitate detection [1-6]. These detection schemes, even if they facilitate transient single-molecule detection [7,8] via consequent formation and cleavage of chemical bonds, typically exhibit time resolutions on the order of milliseconds. The need for analyte immobilisation is a direct consequence of the minuscule dimensions of plasmonic near fields typically providing sub-attolitre-sized detection volumes which in turn demand sub-microsecond temporal resolution for the direct detection of proteins in motion. Here we show that such temporal resolution can indeed be achieved. We demonstrate the observation of single proteins as small as Hemoglobin (molecular weight: 64 kDa) as they traverse plasmonic near fields of gold nanorods and interact with their surface, all while maintaining signal-to-noise ratios larger than 5 and an unprecedented temporal resolution well below microseconds. This method enables the label-free observation of single-molecule dynamics on previously unaccessible timescales.
description: 15 pages, 7 figures
Spinning down newborn neutron stars: nonlinear development of the r-mode instability
Creators: name: Bondarescu, Ruxandra
name: Teukolsky, Saul A.
name: Wasserman, Ira
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We model the nonlinear saturation of the r-mode instability via three-mode couplings and the effects of the instability on the spin evolution of young neutron stars. We include one mode triplet consisting of the r-mode and two near resonant inertial modes that couple to it. We find that the spectrum of evolutions is more diverse than previously thought. The evolution of the star is dynamic and initially dominated by fast neutrino cooling. Nonlinear effects become important when the r-mode amplitude grows above its first parametric instability threshold. The balance between neutrino cooling and viscous heating plays an important role in the evolution. Depending on the initial r-mode amplitude, and on the strength of the viscosity and of the cooling this balance can occur at different temperatures. If thermal equilibrium occurs on the r-mode stability curve, where gravitational driving equals viscous damping, the evolution may be adequately described by a one-mode model. Otherwise, nonlinear effects are important and lead to various more complicated scenarios. Once thermal balance occurs, the star spins-down oscillating between thermal equilibrium states until the instability is no longer active. For lower viscosity we observe runaway behavior in which the r-mode amplitude passes several parametric instability thresholds. In this case more modes need to be included to model the evolution accurately. In the most optimistic case, we find that gravitational radiation from the r-mode instability in a very young, fast spinning neutron star within about 1 Mpc of Earth may be detectable by advanced LIGO for years, and perhaps decades, after formation. Details regarding the amplitude and duration of the emission depend on the internal dissipation of the modes of the star, which would be probed by such detections.
description: 23 pages, 13 figures, 1 table. Submitted to Phys. Rev. D. Detectability discussion expanded. Includes referee input
MPEC 2024-S188 : 2024 SX5
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 SX5

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Nonparametric adaptive estimation for pure jump Lévy processes
Creators: name: Comte, Fabienne
name: Genon-Catalot, Valentine
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: This paper is concerned with nonparametric estimation of the Lévy density of a pure jump Lévy process. The sample path is observed at $n$ discrete instants with fixed sampling interval. We construct a collection of estimators obtained by deconvolution methods and deduced from appropriate estimators of the characteristic function and its first derivative. We obtain a bound for the ${\mathbb L}^2$-risk, under general assumptions on the model. Then we propose a penalty function that allows to build an adaptive estimator. The risk bound for the adaptive estimator is obtained under additional assumptions on the Lévy density. Examples of models fitting in our framework are described and rates of convergence of the estimator are discussed.
Downfolded Self-Energy of Many-Electron Systems
Creators: name: Aryasetiawan, F.
name: Tomczak, J. M.
name: Miyake, T.
name: Sakuma, R.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Starting from the full many-body Hamiltonian of interacting electrons the effective self-energy acting on electrons residing in a subspace of the full Hilbert space is derived. This subspace may correspond to, for example, partially filled narrow bands, which often characterize strongly correlated materials. The formalism delivers naturally the frequency-dependent effective interaction (the Hubbard U) and provides a general framework for constructing theoretical models based on the Green function language. It also furnishes a general scheme for first-principles calculations of complex systems in which the main correlation effects are concentrated on a small subspace of the full Hilbert space.
description: 5 pages
Growth and Dissipation of Be Star Discs in Misaligned Binary Systems
Creators: name: Suffak, M.
name: Jones, C. E.
name: Carciofi, A. C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We use a three-dimensional smoothed particle hydrodynamics code to simulate growth and dissipation of Be star discs in systems where the binary orbit is misaligned with respect to the spin axis of the primary star. We investigate six different scenarios of varying orbital period and misalignment angle, feeding the disc at a constant rate for 100 orbital periods, and then letting the disc dissipate for 100 orbital periods. During the disc growth phase, we find that the binary companion tilts the disc away from its initial plane at the equator of the primary star before settling to a constant orientation after 40 to 50 orbital periods. While the mass-injection into the disc is ongoing, the tilting of the disc can cause material to reaccrete onto the primary star prematurely. Once disc dissipation begins, usually the disc precesses about the binary companion's orbital axis with precession periods ranging from 20 to 50 orbital periods. In special cases we detect phenomena of disc tearing, as well as Kozai-Lidov oscillations of the disc. These oscillations reach a maximum eccentricity of about 0.6, and a minimum inclination of about \ang{20} with respect to the binary's orbit. We also find the disc material to have highly eccentric orbits beyond the transition radius, where the disc changes from being dominated by viscous forces, to heavily controlled by the companion star, in contrast to its nearly circular motion inward of the transition radius. Finally, we offer predictions to how these changes will affect Be star observables.
description: 14 pages, 14 figures
Subleading contributions to the width of the D_{s0}*(2317)
Creators: name: Guo, Feng-Kun
name: Hanhart, Christoph
name: Krewald, Siegfried
name: Meißner, Ulf-G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We construct the effective chiral Lagrangian involving the D--mesons and Goldstone bosons at next-to-leading order taking into account strong as well as electromagnetic interactions. This allows us to disentangle -- to leading order in isospin violation -- the electromagnetic and the strong contribution to the D--meson mass differences. In addition, we also apply the interaction to the decay D_{s0}^*(2317)-> D_s pi0 under the assumption that the D_{s0}^*(2317) is a hadronic molecule. We find (180+-110) keV for the decay width $Γ(D_{s0}^*(2317)-> D_s pi0) -- consistent with currently existing experimental constraints as well as previous theoretical investigations. The result provides further evidence that this decay width can serve as a criterion for testing the nature of the D_{s0}^*(2317).
description: 11 pages, 2 figures
Field exposed water in a nanopore: liquid or vapour?
Creators: name: Bratko, Dusan
name: Daub, Christopher D.
name: Luzar, Alenka
Publisher: name: arXiv
Year: 2008
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We study the behavior of ambient temperature water under the combined effects of nanoscale confinement and applied electric field. Using molecular simulations we analyze the thermodynamic causes of field-induced expansion at some, and contraction at other conditions. Repulsion among parallel water dipoles and mild weakening of interactions between partially aligned water molecules prove sufficient to destabilize the aqueous liquid phase in isobaric systems in which all water molecules are permanently exposed to a uniform electric field. At the same time, simulations reveal comparatively weak field-induced perturbations of water structure upheld by flexible hydrogen bonding. In open systems with fixed chemical potential, these perturbations do not suffice to offset attraction of water into the field; additional water is typically driven from unperturbed bulk phase to the field-exposed region. In contrast to recent theoretical predictions in the literature, our analysis and simulations confirm that classical electrostriction characterizes usual electrowetting behavior in nanoscale channels and nanoporous materials.
description: 20 pages, 6 figures + T.O.C. figure, in press in PCCP
The most filigree structure made by remote laser cutting
Creators: name: Baumann, Robert
name: Herwig, Patrick
name: Beyer, Eckhard
Publisher: name: Technologies for Lightweight Structures (TLS)
Year: 2018

description: It is well known that the global climate change is the largest challenge for the society of the 21th century. In order for us to manage the resulting consequences, innovative materials for energy efficient applications become more and more important. Open cell metal foam contributes promising solutions to the light weight design, battery applications and renewable energy harvesting. Still, challenges are present concerning the cutting into a defined shape. The remote laser cutting offers a solution for decreasing the production costs as well as the needed component accuracy. Our investigations consider that this technique has a high potential concerning cutting speed which was increased by more than 500 %, compared to state of the art laser separation. Next to that, the contour accuracy was improved as well, resulting in tolerances with less than 30 μm. Together with the forceless process of remote laser cutting, the possibility is given to generate filigree components with a wall thickness less than 0.75 pore sizes. This paper offers insight into the viability of remote laser cutting in overcoming the challenges dealing with mechanical milling or grinding. Investigating the process concerning thermal stress input as well as particle attachments will be the next steps in the future.
description: Technologies for Lightweight Structures (TLS), Vol 1, No 2 (2017): Special Issue: 3rd International MERGE Technologies Conference (IMTC), 21st - 22nd September 2017, Chemnitz
Dephasing versus collapse: Lessons from the tight-binding model with noise
Creators: name: Hofmann, Marco
name: Drossel, Barbara
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Condensed matter physics at room temperature usually assumes that electrons in conductors can be described as spatially narrow wave packets - in contrast to what the Schrödinger equation would predict. How a finite-temperature environment can localize wave functions is still being debated. Here, we represent the environment by a fluctuating potential and investigate different unravellings of the Lindblad equation that describes the one-dimensional tight-binding model in the presence of such a potential. While all unravellings show a fast loss of phase coherence, only part of them lead to narrow wave packets, among them the quantum-state diffusion unravelling. Surprisingly, the decrease of the wave packet width for the quantum state diffusion model with increasing noise strength is slower than that of the phase coherence length. In addition to presenting analytical and numerical results, we also provide phenomenological explanations for them. We conclude that as long as no feedback between the wave function and the environment is taken into account, there will be no unique description of an open quantum system in terms of wave functions. We consider this to be an obstacle to understanding the quantum-classical transition.
description: 21 pages, 5 figures
SPIRIT checklist for 'Efficacy of bach flower remedies in individuals with alcohol withdrawal syndrome: A randomized clinical trial protocol
Creators: name: Araujo Rocha, Mayara
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 420699
subject: Public health not elsewhere classified
classificationCode: 420899
subject: Traditional, complementary and integrative medicine not elsewhere classified

description: Background: This study aimed to compare bach flower remedies to placebo in reducing anxiety and craving in individuals with Alcohol Withdrawal Syndrome (AWS).Methods: This is a randomized, double-blind, controlled clinical trial protocol that will be carried out with users with Alcohol Withdrawal Syndrome in a 24-hour follow-up at a Psychosocial Care Center for Alcohol and Other Drugs.
Controlling crop pest with a farming awareness based integrated approach and optimal control
Creators: name: Abraha, Teklebirhan
name: Basir, Fahad Al
name: Obsu, Legesse Lemecha
name: Torres, Delfim F. M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optimization and Control (math.OC)
subject: Quantitative Methods (q-bio.QM)
subject: FOS: Mathematics
subject: FOS: Biological sciences
subject: 49N90, 92D45

description: We investigate a mathematical model in crop pest controlling, considering plant biomass, pest, and the effect of farming awareness. The pest population is divided into two compartments: susceptible pests and infected pests. We assume that the growth rate of self-aware people is proportional to the density of susceptible pests existing in the crop arena. Impacts of awareness are modeled through the usual mass action term and a saturated term. It is further assumed that self-aware people will adopt chemical and biological control methods, namely integrated pest management. Bio-pesticides are costly and require a long-term process, expensive to impose. However, if chemical pesticides are introduced in the farming system along with bio-pesticides, the process will be faster as well as cost-effective. Also, farming knowledge is equally important. In this article, a mathematical model is derived for controlling crop pests through an awareness-based integrated approach. In order to reduce the negative effects of pesticides, we apply optimal control theory.
description: This is a preprint of a paper whose final and definite form is published in 'Computational and Mathematical Methods' [https://onlinelibrary.wiley.com/journal/25777408]. Submitted 26-Jul-2021; Accepted for publication in Computational and Mathematical Methods 17-Sep-2021. arXiv admin note: text overlap with arXiv:2106.08192
Prefinished Metal Polymer Hybrid Parts
Creators: name: Kuehnert, Ines
name: Gedan-Smolka, Michaela
name: Fischer, Matthieu
name: Scholz, Peter
name: Landgrebe, Dirk
name: Garray, Didier
Publisher: name: Technologies for Lightweight Structures (TLS)
Year: 2018

description: In this study, the shaping and assembly behavior of adhesive polymer-metal-composites was investigated in an international cooperation using two step curable uretdione-polyester-based powder coatings (IPF development) which acts simultaneously as a reactive adhesive agent and as a high quality surface finish. To create the composite, a thermoplastic polyurethane (TPU) layer with good compatibility to the powder coating was over-molded onto a powder coated aluminum substrate. A polyamide (PA6) layer was over-molded on to the TPU layer to create a stiff composite structure with possibilities for further functionalization. The TPU-layer in between the metal substrate and the polymer top layer acts as a stress and strain compensation layer. These loads are caused by thermal expansion (under fluctuating temperatures) and external forces/deformation. Another key feature of the composite is the innovative process chain. The powder coating can resist high deformation and therefore the coating is suitable for a future application on to a metal substrate using a coil coating procedure. In addition, the coil could be easily implemented into a production line as a semi-finished product. The prefinished coated metal substrate could be formed (e.g. incremental forming, deep drawing) and inserted in the over-molding procedure. This overall shortened process chain allows not only an effective fabrication of pre-coated semi-finished materials and polymer-metal-joints in high quantities by saving process steps (e.g. cleaning steps, glue application) but also a higher versatility in the following composite production.
description: Technologies for Lightweight Structures (TLS), Vol 1, No 2 (2017): Special Issue: 3rd International MERGE Technologies Conference (IMTC), 21st - 22nd September 2017, Chemnitz
Material-integrated composite humidity sensors for condition monitoring of fiber-reinforced plastics
Creators: name: Martin, Jörg
name: Shetty, Kuldeep
name: Reimann, Nadine
name: Neukirchner, Stephan
name: Fügmann, Uta
name: Illing-Günther, Heike
name: Nestler, Daisy
name: Hübler, Arved C.
name: Nendel, Klaus
name: Kroll, Lothar
name: Otto, Thomas
Publisher: name: Technologies for Lightweight Structures (TLS)
Year: 2018

description: Penetrating water in fiber-reinforced plastics can alter the mechanical properties considerably. To avoid potential resulting failure of the component, we propose continuous monitoring of the humidity inside the material by highly-sensitive humidity sensors based on nano- or microcomposites. Here we report on the inline-capable fabrication and integration of humidity sensors in glass fiber-reinforced polyamide (GF-PA6). Mean water concentrations of less than 0.5 wt. % have been clearly determined inside the laminate.
description: Technologies for Lightweight Structures (TLS), Vol 1, No 2 (2017): Special Issue: 3rd International MERGE Technologies Conference (IMTC), 21st - 22nd September 2017, Chemnitz
Shapes, Softness and Non-Yrast Collectivity in 186W
Creators: name: Prasher, V. S.
name: Mitchell, A. J.
name: Lister, C. J.
name: Chowdhury, P.
name: Afanasieva, L.
name: Albers, M.
name: Chiara, C. J.
name: Carpenter, M. P.
name: Cline, D.
name: D'Olympia, N.
name: Guess, C. J.
name: Hayes, A. B.
name: Hoffman, C. R.
name: Janssens, R. V. F.
name: Kay, B. P.
name: Khoo, T. L.
name: Korichi, A.
name: Lauritsen, T.
name: Merchan, E.
name: Qiu, Y.
name: Seweryniak, D.
name: Shearman, R.
name: Tandel, S. K.
name: Verras, A.
name: Wu, C. Y.
name: Zhu, S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Non-yrast, excited states in neutron-rich $^{186}$W were populated via inelastic-scattering reactions using beams of $^{136}$Xe nuclei accelerated to 725 and 800 MeV. Levels populated in the reactions were investigated via particle-$ γ$ coincidence techniques using the Gammasphere array of High-Purity Germanium detectors and the compact heavy-ion counter, CHICO2. The $ K^π = 2 ^{+} $ ($γ$), $ K^π = 0^{+}$ and $ K^π = 2^{-} $ (octupole) rotational side bands were extended to spins $ 14\hbar $, $ 12\hbar $, and $ 13\hbar $, respectively. A staggering pattern observed in the energies of levels in the $ K^π = 2^{+} $ band was found to be consistent with a potential that gets softer to vibration in the $ γ$ degree of freedom with increasing spin. The odd-even staggering of states in the $ K^π = 2^{-}$ band was found to exhibit a phase opposite to that seen in the $ γ$ band; an effect most probably associated with Coriolis coupling to other, unobserved octupole vibrational bands in $^{186}$W.
description: 14 pages, 16 figures
MPEC 2024-S189 : 2024 SY5
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 SY5

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Primitive normalisers in quasipolynomial time
Creators: name: Chang, Mun See
name: Roney-Dougal, Colva M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: F.2.2; G.2.1
subject: 20-08 (Primary) 20B35, 68W30 (Secondary)

description: The normaliser problem has as input two subgroups $H$ and $K$ of the symmetric group $S_n$, and asks for a generating set for $N_K(H)$: it is not known to have a subexponential time solution. It is proved in [Roney-Dougal & Siccha, 2020] that if $H$ is primitive then the normaliser problem can be solved in quasipolynomial time. We show that for all subgroups $H$ and $K$ of $S_n$, in quasipolynomial time we can decide whether $N_{S_n}(H)$ is primitive, and if so compute $N_K(H)$. Hence we reduce the question of whether one can solve the normaliser problem in quasipolynomial time to the case where the normaliser is known not to be primitive.
Long 48-cm ULE cavities in vertical and horizontal orientations for Sr optical clock
Creators: name: Zhadnov, Nikita
name: Kudeyarov, Konstantin
name: Kryuchkov, Denis
name: Vishnyakova, Gulnara
name: Khabarova, Ksenia
name: Kolachevsky, Nikolay
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The development of an optical clock with ultimate accuracy and stability requires lasers with very narrow linewidth. We present two ultrastable laser systems based on 48 cm long Fabry-Perot cavities made of ULE glass in horizontal and vertical configurations operating at 698 nm. Fractional frequency instability of the beat signal between two lasers reaches 1.6e-15 at the averaging time of 1 s. We experimentally characterized the contribution of the different noise sources (power fluctuations, residual amplitude modulation, the Doppler noise, sensitivity to the shock impact) and found that in our case the laser frequency instability to a large extent is determined by an optoelectronic feedback loop. Although the vertical configuration proved to be easier to manufacture and to transport, it turned out that it is much more sensitive to acoustics and horizontal accelerations compared to the horizontal one. Both laser systems were transported over a 60 km distance from the Lebedev Physical Institute to the Russian National Metrology Institute (VNIIFTRI) where they serve as local oscillators for spectroscopy of the clock transition in the recently developed strontium optical clock.
description: 17 pages, 11 figures
The Transition from Generation-Recombination Noise in Bulk Semiconductors to Discrete Switching in Small-Area Semiconductors
Creators: name: Grueneis, F.
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: The master-equation approach provides generation-recombination (g-r) noise in bulk semiconductors in terms of parameters of conduction electrons. It is shown that the g-r bulk noise can also be described by the random succession of elementary g-r pulses. This enables g-r bulk noise to be interpreted in terms of the numbers of traps. The transition from g-r bulk noise to discrete switching in small-area semiconductors is found by reducing the number of traps to just one single active trap. The resulting g-r noise spectrum is shown to be equivalent to Machlups noise spectrum. The probability of an overlap of succeeding g-r pulses is calculated. Such an overlap is attributed to the occupation of an empty single trap by an electron transferred from a neighboring trap. Simulating a g-r pulse train we find a large variety of patterns similar to those observed in MOSFETs. Excluding overlapping g-r pulses, the up and down distribution of succeeding g-r pulses is estimated.
description: 13 pages, 9 figures and addendum
phlibitis ethical.pdf
Creators: name: Gedefaw, Gezahagn
Publisher: name: figshare
Year: 2025
Subjects: classificationCode: 420501
subject: Acute care

description: Neonates admitted to hospitals require vascular access for various purposes, such as fluid or drug administration, blood transfusion, and diagnostic procedures. The insertion of a peripheral intravascular line is essential for the care of neonates in the neonatal intensive care unit (NICU) and is one of the most common invasive procedures
Visualizing band selective enhancement of quasiparticle lifetime in a metallic ferromagnet
Creators: name: Jo, Na Hyun
name: Wu, Yun
name: Trevisan, Thaís V.
name: Wang, Lin-Lin
name: Lee, Kyungchan
name: Kuthanazhi, Brinda
name: Schrunk, Benjamin
name: Bud'ko, S. L.
name: Canfield, P. C.
name: Orth, P. P.
name: Kaminski, Adam
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Electrons navigate more easily in a background of ordered magnetic moments than around randomly oriented ones. This fundamental quantum mechanical principle is due to their Bloch wave nature and also underlies ballistic electronic motion in a perfect crystal. As a result, a paramagnetic metal that develops ferromagnetic order often experiences a sharp drop in the resistivity. Despite the universality of this phenomenon, a direct observation of the impact of ferromagnetic order on the electronic quasiparticles in a magnetic metal is still lacking. Here we demonstrate that quasiparticles experience a significant enhancement of their lifetime in the ferromagnetic state of the low-density magnetic semimetal EuCd2As2, but this occurs only in selected bands and specific energy ranges. This is a direct consequence of the magnetically induced band splitting and the multi-orbital nature of the material. Our detailed study allows to disentangle different electronic scattering mechanisms due to non-magnetic disorder and magnon exchange. Such high momentum and energy dependence quasiparticle lifetime enhancement can lead to spin selective transport and potential spintronic applications.
description: 15 pages, 4 figures + supplement
Linguistic form: a political epistemology
Creators: name: Riemer, Nick
Publisher: name: Zenodo
Year: 2019

description: This chapter explores ideological dimensions of contemporary mainstream linguistics, especially with reference to the ``unique form hypothesis'': the assumption that each language has a single form, which it is the role of linguistics to characterize. The chapter surveys grounds for scepticism about the hypothesis, reviews some recent ideological critiques of linguistics, and sketches the contours of a speculative ``political epistemology'' of the unique form hypothesis, suggesting how well-known critiques of the other social sciences might apply to structural linguistics research. It pays special attention to the unique form hypothesis' role as a vehicle for the discretionary intellectual authority of the linguistic expert -- in the pedagogical context, the lecturer who serves as the origin and authority of the ideas about language structure transmitted to the linguistics student. This authority is argued to replicate and so to normalize, in the domain of education, the kinds of relations of social domination on which contemporary political orders rest. As a result of this discussion, the theoretical biases of contemporary linguistics are replaced in the broader socio-ideological context to which they belong, and considered with respect to some classic political critiques of ``bourgeois'' social science.\label{q:riemer:domination