cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Constrained mixers for the quantum approximate optimization algorithm
Creators: name: Fuchs, Franz G.
name: Lye, Kjetil Olsen
name: Nilsen, Halvor Møll
name: Stasik, Alexander J.
name: Sartor, Giorgio
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The quantum approximate optimization algorithm/quantum alternating operator ansatz (QAOA) is a heuristic to find approximate solutions of combinatorial optimization problems. Most literature is limited to quadratic problems without constraints. However, many practically relevant optimization problems do have (hard) constraints that need to be fulfilled. In this article, we present a framework for constructing mixing operators that restrict the evolution to a subspace of the full Hilbert space given by these constraints; We generalize the "XY"-mixer designed to preserve the subspace of "one-hot" states to the general case of subspaces given by a number of computational basis states. We expose the underlying mathematical structure which reveals more of how mixers work and how one can minimize their cost in terms of number of CX gates, particularly when Trotterization is taken into account. Our analysis also leads to valid Trotterizations for "XY"-mixer with fewer CX gates than is known to date. In view of practical implementations, we also describe algorithms for efficient decomposition into basis gates. Several examples of more general cases are presented and analyzed.
title: Fabrication of biomimetic networks using viscous fingering in flexographic printing
Creators: name: Brumm, Pauline
name: Fritschen, Anna
name: Doß, Lara
name: Dörsam, Edgar
name: Blaeser, Andreas
Publisher: name: IOP Publishing
Year: 2022

description: Mammalian tissue comprises a plethora of hierarchically organized channel networks that serve as routes for the exchange of liquids, nutrients, bio-chemical cues or electrical signals, such as blood vessels, nerve fibers, or lymphatic conduits. Despite differences in function and size, the networks exhibit a similar, highly branched morphology with dendritic extensions. Mimicking such hierarchical networks represents a milestone in the biofabrication of tissues and organs. Work to date has focused primarily on the replication of the vasculature. Despite initial progress, reproducing such structures across scales and increasing biofabrication efficiency remain a challenge. In this work, we present a new biofabrication method that takes advantage of the viscous fingering phenomenon. Using flexographic printing, highly branched, inter-connective channel structures with stochastic, biomimetic distribution and dendritic extensions can be fabricated with unprecedented efficiency. Using gelatin (5%–35%) as resolvable sacrificial material, the feasability of the proposed method is demonstrated on the example of a vascular network. By selectively adjusting the printing velocity (0.2–1.5 m s⁻¹), the anilox roller dip volume (4.5–24 ml m⁻²) as well as the shear viscosity of the printing material used (10–900 mPas), the width of the structures produced (30–400 µm) as well as their distance (200–600 µm) can be specifically determined. In addition to the flexible morphology, the high scalability (2500–25 000 mm²) and speed (1.5 m s⁻¹) of the biofabrication process represents an important unique selling point. Printing parameters and hydrogel formulations are investigated and tuned towards a process window for controlled fabrication of channels that mimic the morphology of small blood vessels and capillaries. Subsequently, the resolvable structures were casted in a hydrogel matrix enabling bulk environments with integrated channels. The perfusability of the branched, inter-connective structures was successfully demonstrated. The fabricated networks hold great potential to enable nutrient supply in thick vascularized tissues or perfused organ-on-a-chip systems. In the future, the concept can be further optimized and expanded towards large-scale and cost-efficient biofabrication of vascular, lymphatic or neural networks for tissue engineering and regenerative medicine.
Sonnenfleckenzeichnung unnummeriert, einen Zürcher Lückentag ergänzend.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 06.11.1942, erstellt von Enrique Gullon an der Sternwarte Madrid
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Zeichnung mit Tinte, erstellt auf einem eigenen Vordruck in Madrid. Instrument: Grubb Refraktor Teleskop (Öffnung: 20 cm, f = 3 m, projiziertes Sonnenbild D = 6,5 cm).
Instrumentennachweis gemäss Aparicio (u.a.): Sunspot, in: Solar Physics, Vol. 289, S. 4335-49, DOI: 10.1007/s11207-014-0567-x
Mixed dispersion nonlinear Schrödinger equation in higher dimensions: theoretical analysis and numerical computations
Creators: name: Stefanov, A.
name: Tsolias, G. A.
name: Cuevas-Maraver, J.
name: Kevrekidis, P. G.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: In the present work we provide a characterization of the ground states of a higher-dimensional quadratic-quartic model of the nonlinear Schr{ö}dinger class with a combination of a focusing biharmonic operator with either an isotropic or an anisotropic defocusing Laplacian operator (at the linear level) and power-law nonlinearity. Examining principally the prototypical example of dimension $d=2$, we find that instability arises beyond a certain threshold coefficient of the Laplacian between the cubic and quintic cases, while all solutions are stable for powers below the cubic. Above the quintic, and up to a critical nonlinearity exponent $p$, there exists a progressively narrowing range of stable frequencies. Finally, above the critical $p$ all solutions are unstable. The picture is rather similar in the anisotropic case, with the difference that even before the cubic case, the numerical computations suggest an interval of unstable frequencies. Our analysis generalizes the relevant observations for arbitrary combinations of Laplacian prefactor $b$ and nonlinearity power $p$.
Sonnenfleckenzeichnung Nr. 15222.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 09.10.1942, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt
Ca II Triplet Spectroscopy of Small Magellanic Cloud Red Giants. V. Abundances and Velocities for 12 Massive Clusters
Creators: name: Parisi, M. C.
name: Gramajo, L. V.
name: Geisler, D.
name: Dias, B.
name: Clariá, J. J.
name: Da Costa, G.
name: Grebel, E. K.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We aim to analyze the chemical evolution of the Small Magellanic Cloud adding 12 additional clusters to our existing sample having accurate and homogeneously derived metallicities. We are particularly interested in seeing if there is any correlation between age and metallicity for the different structural components to which the clusters belong. Spectroscopic metallicities of red giant stars are derived from the measurement of the equivalent width of the near-IR calcium triplet lines. Cluster membership analysis was carried out using criteria that include radial velocities, metallicities, proper motions and distance from the cluster center. The mean cluster radial velocity and metallicity were determined with a typical error of 2.1 km/s and 0.03 dex, respectively. We added this information to that available in the literature for other clusters studied with the same method, compiling a final sample of 48 clusters with metallicities homogeneously determined. Clusters of the final sample are distributed in an area of ~ 70 deg^2 and cover an age range from 0.4 Gyr to 10.5 Gyr. The metallicity distribution of our new cluster sample shows a lower probability of being bimodal than suggested in previous studies. The separate chemical analysis of clusters in the six components (Main Body, Counter-Bridge, West Halo, Wing/Bridge, Northern Bridge and Southern Bridge) shows that only clusters belonging to the Northern Bridge appear to trace a V-Shape, showing a clear inversion of the metallicity gradient in the outer regions. There is a suggestion of a metallicity gradient in the West Halo, similar to that previously found for field stars. It presents, however, a very large uncertainty. Also, clusters belonging to the West Halo, Wing/Bridge and Southern Bridge exhibit a well-defined age-metallicity relation with relatively little scatter in abundance at fixed age compared to other regions.
description: 16 pages, 18 figures,Accepted for publication in A&A
Sonnenfleckenzeichnung unnummeriert, einen Zürcher Lückentag ergänzend.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 30.11.1942, erstellt von Enrique Gullon an der Sternwarte Madrid
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Zeichnung mit Tinte, erstellt auf einem eigenen Vordruck in Madrid. Instrument: Grubb Refraktor Teleskop (Öffnung: 20 cm, f = 3 m, projiziertes Sonnenbild D = 6,5 cm).
Instrumentennachweis gemäss Aparicio (u.a.): Sunspot, in: Solar Physics, Vol. 289, S. 4335-49, DOI: 10.1007/s11207-014-0567-x
Monte Carlo Simulation of Sugar Synthesis on Icy Dust Particles Intermittently Irradiated by UV in a Protoplanetary Disk
Creators: name: Takehara, Hitoshi
name: Shoji, Daigo
name: Ida, Shigeru
Publisher: name: arXiv
Year: 2022
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Context. While synthesis of organic molecules in molecular clouds or protoplanetary disks is complex, observations of interstellar grains, analyses of carbonaceous chondrites, and UV photochemistry experiments are rapidly developing and providing constraints on and clues to the complex organic molecule synthesis in space. It motivates us to construct a theoretical synthesis model. Aims. We develop a new code to simulate global reaction sequences of organic molecules to apply it for sugar synthesis by intermittent UV irradiation on the surface of icy particles in a protoplanetary disk. Here we show the first results of our new simulation. Methods. We apply a Monte Carlo method to select reaction sequences from all possible reactions, using the graph-theoretic matrix model for chemical reactions and modeling reactions on the icy particles during UV irradiation. Results. We here obtain the results consistent with the organic molecules in carbonaceous chondrites and obtained by the experiments, however, through a different pathway from the conventional formose reactions previously suggested. During UV irradiation, loosely-bonded O-rich large molecules are continuously created and destroyed. After UV irradiation is turned off, the ribose abundance rapidly increases, through the decomposition of the large molecules with break-ups of O-O bonds and replacements of C-OH by C-H to reach O/C = 1 for sugars. The sugar abundance is regulated mostly by the total atomic ratio H/O of starting materials, but not by their specific molecule forms. Deoxyribose is simultaneously synthesized, and most of the molecules end up with complex C-rich molecules.
description: 14 pages, accepted for publication in Astronomy and Astrophysics
O'ZBEKISTON RESPUBLIKASI IQTISODIYoTINI RAQAMLASHTIRISH  SHAROITIDA ELEKTRON TIJORATNI DAVLAT BOSHQARUV MEXANIZMLARINI TAKOMILLASHTIRISH
Creators: name: Axmedova, Y.
Publisher: name: Zenodo
Year: 2024

description: Raqamli texnologiyalar hayotimizga o'zini tanitib, raqamli platformalarni va keyinchalik raqamli ekotizimlarni yaratadi, o'zaro ta'sirning yangi shartlarini belgilaydi, yangi biznes jarayonlarini shakllantiradi. Strategiyaga ko'ra “Raqamli O‘zbekiston 2030” hukumati raqamli iqtisodiyot, jumladan, elektron tijoratni rivojlantirish uchun qulay shart-sharoitlar yaratishga intilmoqda. Raqamli platformalar va ekotizimlardan foydalangan holda o‘zaro hamkorlikning yangi shartlarini hisobga olgan holda xo‘jalik yurituvchi subyektlar o‘rtasidagi munosabatlarni huquqiy tartibga solish zarur.
Sonnenfleckenzeichnung Nr. 15197.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 11.09.1942, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt
Sonnenfleckenzeichnung Nr. 15180.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 24.08.1942, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt
Sonnenfleckenzeichnung Nr. 15208.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 23.09.1942, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt
Spin-chain-star systems: entangling multiple chains of spin qubits
Creators: name: Grimaudo, R.
name: de Castro, A. S. M.
name: Messina, A.
name: Valenti, D.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We consider spin-chain-star systems characterized by N-wise many-body interactions between the spins in each chain and the central one. We show that such systems can be exactly mapped into standard spin-star systems through unitary transformations. Such an approach allows the solution of the dynamic problem of an XX spin-chain-star model and transparently shows the emergence of quantum correlations in the system, based on the idea of entanglement between chains.
Sonnenfleckenzeichnung unnummeriert, einen Zürcher Lückentag ergänzend.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 08.11.1942, erstellt von Enrique Gullon an der Sternwarte Madrid
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Zeichnung mit Tinte, erstellt auf einem eigenen Vordruck in Madrid. Instrument: Grubb Refraktor Teleskop (Öffnung: 20 cm, f = 3 m, projiziertes Sonnenbild D = 6,5 cm).
Instrumentennachweis gemäss Aparicio (u.a.): Sunspot, in: Solar Physics, Vol. 289, S. 4335-49, DOI: 10.1007/s11207-014-0567-x
Two-photon Annihilation of Positrons with K-shell Electrons of H-like ions
Creators: name: Mandrykina, Z. A.
name: Zaytsev, V. A.
name: Yerokhin, V. A.
name: Shabaev, V. M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The two-photon annihilation of a positron with an electron bound in the 1s state of a H-like ion is calculated within the fully relativistic QED framework. The interaction with the nucleus is treated nonperturbatively, thus allowing the calculations to be carried out for the annihilation with strongly-bound inner shells of heavy ions. Infrared divergences, appearing when one of the emitted photons approaches the low-frequency limit, are accurately eliminated from final expressions. The total cross section of the two-photon and one-photon annihilation processes are compared for a wide range of collision energies and nuclear charge numbers. It is demonstrated that the two-photon annihilation channel dominates over the one-photon channel for the low and medium-Z ions, whereas for the high-Z ions the situation reverses.
description: 18 pages, 5 figures
The multipolar structure of rotating boson stars
Creators: name: Vaglio, Massimo
name: Pacilio, Costantino
name: Maselli, Andrea
name: Pani, Paolo
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The relativistic multipole moments provide a key ingredient to characterize the gravitational field around compact astrophysical objects. They play a crucial role in the description of the orbital evolution of coalescing binary systems and encode valuable information on the nature of the binary's components, which leaves a measurable imprint in their gravitational-wave emission. We present a new study on the multipolar structure of a class of arbitrarily spinning boson stars with quartic self-interactions in the large coupling limit, where these solutions are expected to be stable. Our results strengthen and extend previous numerical analyses, showing that even for the most compact configurations the multipolar structure deviates significantly from that of a Kerr black hole. We provide accurate data for the multipole moments as functions of the object's mass and spin, which can be directly used to construct inspiral waveform approximants and to perform parameter estimations and searches for boson star binaries.
description: 11+3 pages, 11 figures, data for the quadrupole and octupole moments available at https://web.uniroma1.it/gmunu
A spectroscopic survey of infrared 1-4μm spectra in regions of prominent solar coronal emission lines of Fe XIII, Si X, and Si IX
Creators: name: Ali, Aatiya
name: Paraschiv, Alin
name: Reardon, Kevin
name: Judge, Philip
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The infrared solar spectrum contains a wealth of physical data about the Sun and is being explored using modern detectors and technology with new ground-based solar telescopes. One such instrument will be the ground-based Cryogenic Near-IR Spectro-Polarimeter of the Daniel K. Inouye Solar Telescope that will be capable of sensitive imaging of the faint infrared solar coronal spectra with full Stokes I, Q, U, and V polarization states. Highly ionized magnetic dipole emission lines have been observed in galaxies and the solar corona. Quantifying the accuracy of spectral inversion procedures requires a precise spectroscopic calibration of observations. A careful interpretation of the spectra around prominent magnetic dipole lines is essential for deriving physical parameters, and particularly, for quantifying the off-limb solar coronal observations from DKIST. In this work, we aim to provide an analysis of the spectral regions around the infrared coronal emission lines of Fe XIII 1074.68 nm, Fe XIII 1079.79 nm, Si X 1430.10 nm, and Si IX 3934.34 nm, aligning with the goal of identifying solar photospheric and telluric lines that will help facilitate production of reliable inversions and data products from four sets of solar coronal observations. The outputs will be integrated in the processing pipeline to produce Level-2 science-ready data that will be made available to DKIST observers.
Sonnenfleckenzeichnung unnummeriert, einen Zürcher Lückentag ergänzend.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 21.10.1942, erstellt von Gaston Coutrez, Observatoire Royal de Belgique in Uccle
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift, erstellt als Zeichnung nach eigener Vorlage in Uccle, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E).
Instrument: Merz-Grubb Refraktor Teleskop (Öffnung 160 mm, f = 2450 mm, projiziertes Sonnenbild D = 25 cm)
Sonnenfleckenzeichnung Nr. 15203.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 17.09.1942, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Später wurden ergänzende Angaben aufgrund auswärtiger Beobachtungen direkt auf der Fleckenzeichnung hinzugefügt. Unter Umständen sind Angaben zu Protuberanzen vermerkt
Sonnenfleckenzeichnung Nr. 15156.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 30.07.1942, erstellt von William Brunner, Assistent.
Die Nummer 15156, bereits benutzt für die Zeichnung vom 09.06.1942, wurde für den 30.07.1942 ein zweites Mal vergeben. Die duplizierende Nummer entstand aufgrund mangelhafter Nummernvergabe bereits bei der vorhergehenden Zeichnung
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt
Phonon renormalization and Pomeranchuk instability in the Holstein model
Creators: name: Cichutek, Niklas
name: Hansen, Max
name: Kopietz, Peter
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The Holstein model with dispersionless Einstein phonons is one of the simplest models describing electron-phonon interactions in condensed matter. A naive extrapolation of perturbation theory in powers of the relevant dimensionless electron-phonon coupling $λ_0$ suggests that at zero temperature the model exhibits a Pomeranchuk instability characterized by a divergent uniform compressibility at a critical value of $λ_0$ of order unity. In this work, we re-examine this problem using modern functional renormalization group (RG) methods. For dimensions $d > 3$ we find that the RG flow of the Holstein model indeed exhibits a tricritical fixed point associated with a Pomeranchuk instability. This non-Gaussian fixed point is ultraviolet stable and is closely related to the well-known ultraviolet stable fixed point of $ϕ^3$-theory above six dimensions. To realize the Pomeranchuk critical point in the Holstein model at fixed density both the electron-phonon coupling $λ_0$ and the adiabatic ratio $ω_0 / ε_F$ have to be fine-tuned to assume critical values of order unity, where $ω_0$ is the phonon frequency and $ε_F$ is the Fermi energy. On the other hand, for dimensions $d \leq 3$ we find that the RG flow of the Holstein model does not have any critical fixed points. This rules out a quantum critical point associated with a Pomeranchuk instability in $d \leq 3$.
description: 17 pages, 7 figures
title: Cooling energy saving mechanisms for Data Centers
Creators: name: Nazurmetov, Ahadulla
Publisher: name: TU Wien
Year: 2022
Subjects: subject: datacenter cooling
subject: datacenter efficiency
subject: power usage efficiency
subject: datacenter cooling optimisation

description: Globally, data centers' energy requirements are expanding at a fast pace, asare their environmental and economic impacts. Typically, data centers are quite anenergy hungry. The annual cost of powering a big data center, including computers and cooling equipment, may be approximately $4 million. Energy prices may account for up to 60% of operational costs. According to recent research from the Department of Energy's Lawrence Berkeley National Laboratory, data centers in the United States use a significant amount of energy – around 70 billion kilowatt-hours each year. The electrical energy consumption for data centers in Germany is 16 billion kilowatt-hours per year – up 8% over the previous year in 2020. This increase is mostly attributable to the rapid rise of cloud computing capability. The energy used directly by servers is just one aspect of the picture. Almost every unit of energy used by a server is converted to heat in the building in which it is located, requiring air-conditioning systems to work harder than they would otherwise. Because ITsystems often emit large amounts of heat and have a high need for temperature and humidity management in data centers, a cooling and air conditioning system is required. According to a recent study, refrigeration, and air conditioning systems account for around 40% of overall data center power use. As a result, decreasing the energy consumption of the air conditioning system is critical for overall datacenter energy efficiency.This thesis describes in detail the cooling systems used in the data center’s industry, as well as the modern immersion cooling system. A comparative analysis of the effectiveness of immersion cooling in comparison with the traditional aircooled system is conducted. On the example of a real data center, metrics analyzes in detail, showing how effectively the data center is optimized. The last chapter provides in detail the waste heat recuperation technology.This thesis provides practical information to the data center engineers regarding the cooling system design and supports them to achieve better cooling energy efficiency.
Improved short-segment detection statistic for continuous gravitational waves
Creators: name: Covas, P. B.
name: Prix, R.
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Continuous gravitational waves represent one of the long-sought types of signals that have yet to be detected. Due to their small amplitude, long observational datasets (months-years) have to be analyzed together, thereby vastly increasing the computational cost of these searches. All-sky searches face the most severe computational obstacles, especially searches for sources in unknown binary systems, which need to break the data into very short segments in order to be computationally feasible. In this paper, we present a new detection statistic that improves sensitivity by up to 19% compared to the standard $\mathcal{F}$-statistic for segments shorter than a few hours.
description: 11 pages
Sonnenfleckenzeichnung Nr. 15499.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 27.08.1943, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1943

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt
The UV 2175Å Attenuation Bump and its Correlation with PAH Emission at z~2
Creators: name: Shivaei, Irene
name: Boogaard, Leindert
name: Díaz-Santos, Tanio
name: Battisti, Andrew
name: Brinchmann, Jarle
name: da Cunha, Elisabete
name: Maseda, Michael
name: Matthee, Jorryt
name: Monreal-Ibero, Ana
name: Nanayakkara, Themiya
name: Popping, Gergö
name: Vidal-García, Alba
name: Weilbacher, Peter M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The UV bump is a broad absorption feature centered at 2175Å that is seen in the attenuation/extinction curve of some galaxies, but its origin is not well known. Here, we use a sample of 86 star-forming galaxies at z=1.7-2.7 with deep rest-frame UV spectroscopy from the MUSE HUDF Survey to study the connection between the strength of the observed UV 2175Å bump and the Spitzer/MIPS 24 micron photometry, which at the redshift range of our sample probes mid-IR polycyclic aromatic hydrocarbon (PAH) emission at ~6-8 micron. The sample has robust spectroscopic redshifts and consists of typical main-sequence galaxies with a wide range in stellar mass (log(Mstar/Msun) ~ 8.5-10.7) and star formation rates (SFRs; SFR ~ 1-100 Msun/yr). Galaxies with MIPS detections have strong UV bumps, except for those with mass-weighted ages younger than ~150 Myr. We find that the UV bump amplitude does not change with SFR at fixed stellar mass but increases with mass at fixed SFR. The UV bump amplitude and the PAH strength (defined as mid-IR emission normalized by SFR) are highly correlated and both also correlate strongly with stellar mass. We interpret these correlations as the result of the mass-metallicity relationship, such that at low metallicities PAH emission is weak due to a lower abundance of PAH molecules. The weak or complete absence of the 2175Å bump feature on top of the underlying smooth attenuation curve at low mass/metallicities is then expected if the PAH carriers are the main source of the additional UV absorption.
description: 9 pages, 7 figures, accepted for publication in mnras
Sonnenfleckenzeichnung unnummeriert, einen Zürcher Lückentag ergänzend.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 13.10.1942, erstellt von Gaston Coutrez, Observatoire Royal de Belgique in Uccle
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift, erstellt als Zeichnung nach eigener Vorlage in Uccle.
Instrument: Merz-Grubb Refraktor Teleskop (Öffnung 160 mm, f = 2450 mm, projiziertes Sonnenbild D = 25 cm)
title: Data Spotlight #4
Creators: name: Jedinger, Alexander
name: Feldhausen, Miriam
Publisher: name: GESIS - Leibniz Institute for the Social Sciences
publisherIdentifier: https://ror.org/018afyw53
Year: 2024
Subjects: subject: Curated Data
subject: Data Collection
subject: Climate Change
subject: ISSP
subject: Survey Data
subject: GLES
subject: GESIS Panel
subject: German Internet Panel
subject: Climate Crisis

description: GESIS has curated a thematic collection on climate change and environmental protection, which includes survey data on topics such as climate change, energy policy, environmental awareness, transportation, and sustainability.
description: GESIS hat eine thematische Daten-Sammlung zu Klimawandel und Umweltschutz zusammengestellt, die Umfragedaten zu Themen wie Klimawandel, Energiepolitik, Umweltbewusstsein, Verkehr und Nachhaltigkeit enthält.
description: GESIS Blog
Sonnenfleckenzeichnung unnummeriert, einen Zürcher Lückentag ergänzend.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 22.10.1942, erstellt  in Zürich aufgrund der eingesandten Zeichnung von Karl Rapp in Locarno-Monti
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf dem Vordruck der Eidgenössischen Sternwarte Zürich. Instrument in Locarno: Spiegelfernrohr, Öffnung von 11 cm, Okular von 88facher Vergrösserung, Beobachtungen mit einem Graukeil.
Blatt mit weiterer Bearbeitung der Werte in Zürich
title: Just revolutionary violence: on the possibility of novelty in political life
Creators: name: Butera, Stephanie
Publisher: name: Memorial University of Newfoundland
Year: 2017

description: This thesis addresses two interrelated issues. The first is how we come to think and enact the possibility of overturning the political order in which we find ourselves. This is of particular issue when we consider that our situations always over-determine our possibilities for thinking and acting. The second issue involves the question of how revolutionary violence can be said to be just, or in other words how the act of violence can avoid reinscribing a state of affairs only superficially different from the violent one it sought to overturn. I address these issues using the works of Frantz Fanon and Alain Badiou, two figures in the existential-phenomenological tradition. Fanon’s phenomenological account of oppression gives us a concrete context for thinking the conditions of revolutionary action as presented by Badiou’s ontology. I argue that Badiou’s ontology can account for the lived experience of political oppression as well as the possibility revolutionary violence, despite its “Platonic” idealism.
An RF Timer of Electrons and Photons with the Potential to reach Picosecond Precision
Creators: name: Margaryan, Amur
name: Kakoyan, Vanik
name: Zhamkochyan, Simon
name: Abrahamyan, Sergey
name: Elbakyan, Hayk
name: Mayilyan, Samvel
name: Vardanyan, Henrik
name: Zohrabyan, Hamlet
name: Gevorgian, Lekdar
name: Ayvazyan, Robert
name: Papyan, Artashes
name: Ayvazyan, Garnik
name: Grigoryan, Bagrat
name: Annand, John
name: Livingston, Kenneth
name: Montgomery, Rachel
name: Achenbach, Patrick
name: Pochodzalla, Josef
name: Balabanski, Dimiter L.
name: Nakamura, Satoshi N.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: This paper describes a new radio frequency timer of keV energy electrons. It is based on a helical deflector, which performs circular or elliptical sweeps of keV electrons, by means of 500 MHz radio frequency field. By converting a time distribution of incident electrons to a hit position distribution on a circle or ellipse, this device achieves extremely precise timing. Streak Cameras, based on similar principles, routinely operate in the ps and sub-ps time domain, but have substantial dead time associated with the readout system. Here, we report a new type of RF timing technique, where the position sensor, consisting of microchannel plates and a delay-line anode, produces ~ns duration pulses with small dead time. Measurements made with sub-ps duration laser pulses, synchronized to the radio frequency power, produced a timing resolution of ~10 ps. This ultra-high precision technique has potential applications in a large variety of scientific devices, and in all cases, electrons are timed and detected simultaneously in the same device.
description: 12 pages, 7 figures
Sonnenfleckenzeichnung Nr. 15187.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 31.08.1942, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt
In-situ probing and stabilizing the power ratio of electro-optic-modulated laser pairs based on VIPA etalon for quantum sensing
Creators: name: Wang, Guochao
name: Yang, Mingyue
name: Wang, Enlong
name: Zhang, Xu
name: Jia, Aiai
name: Zhu, Lingxiao
name: Yan, Shuhua
name: Yang, Jun
Publisher: name: arXiv
Year: 2022
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Monitoring and stabilizing the power ratio of laser pairs is significant to high-precision atom interferometers, especially as the compact electro-optic modulated all-fiber laser system prevails. In this Letter, we demonstrate a novel method to in-situ probe the relative power of laser pairs and to stabilize the power ratio of two Raman lasers using a high-dispersion virtually imaged phased array (VIPA) etalon. Sub-microsecond resolution on probing laser power transformation during atom interferometer sequence is achieved and the power ratio of two Raman lasers (PRTR) is tightly locked with high bandwidth despite of environmental disturbances, showing an Allan deviation of $4.39\times 10^{-5}$ at 1000 s averaging time. This method provides a novel way to stabilize the PRTR and diagnose the multi-frequency laser systems for atom interferometers and could find potential application in broad quantum sensing scenarios.
description: 4 pages, 6 figures
Sonnenfleckenzeichnung Nr. 15460.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 19.07.1943, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1943

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt
Neutron skin systematics from microscopic equations of state
Creators: name: Sammarruca, Francesca
Publisher: name: arXiv
Year: 2022
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: This paper presents an analysis of neutron skins based on fully microscopic equations of state, including chiral two- and three-nucleon forces consistently at N3LO. Other theoretical predictions and recent constraints are also addressed, such as those from the PREX II experiment and the latest parity-violating electron scattering measurement of the 27Al neutron skin.
description: Revised version, to appear in Physical Review C
Sonnenfleckenzeichnung Nr. 15198.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 12.09.1942, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt
Long lifetime supersolid in a two-component dipolar Bose-Einstein condensate
Creators: name: Li, Shaoxiong
name: Le, Uyen Ngoc
name: Saito, Hiroki
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Recent studies on supersolidity in a single-component Bose-Einstein condensate (BEC) have relied on the Lee-Huang-Yang (LHY) correction for stabilization of self-bound droplets, which however involves a high density inside the droplets, limiting the lifetime of the supersolid. Here we propose a two-component mixture of dipolar and nondipolar BECs, such as an $^{166}$Er-$^{87}$Rb mixture, to create and stabilize a supersolid without the LHY correction, which can suppress the atomic loss and may allow observation of the long-time dynamics of the supersolid. In such a system, supersolidity can be controlled by the difference in the trap centers between the two components.
description: 7 pages, 3 figures
Chemins Vers Les Biens Communs De La Connaissance Et La Démocratie Scientifique
Creators: name: Piron, Florence
Publisher: name: Zenodo
Year: 2018
Subjects: démocratie scientifique, biens communs, justice cognitive,

description: Conférence donnée lors de la quatrième session de l'Université du bien commun intitulée : "La technologisation de la vie et ses conséquences. Les technosciences en démocratie".

Établissement Culturel Solidaire

100, rue de Charenton, 75012 Paris, le 13 janvier 2017.
Logarithmic convexity and impulsive controllability for the 1-D heat equation with dynamic boundary conditions
Creators: name: Chorfi, S. E.
name: Guermai, G. El
name: Maniar, L.
name: Zouhair, W.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optimization and Control (math.OC)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35R12, 49N25, 93C27

description: In this paper, we prove a logarithmic convexity that reflects an observability estimate at a single point of time for 1-D heat equation with dynamic boundary conditions. Consequently, we establish the impulse approximate controllability for the impulsive heat equation with dynamic boundary conditions. Moreover, we obtain an explicit upper bound of the cost of impulse control. At the end, we give a constructive algorithm for computing the impulsive control of minimal $L^2$-norm. We also present some numerical tests to validate the theoretical results and show the efficiency of the designed algorithm.
description: 22 pages, 4 figures, 1 table
The lost Missal of Alcuin and the Carolingian sacramentaries of Tours
Creators: name: Westwell, Arthur
Publisher: name: Universität Regensburg
Year: 2022
Subjects: subject: 200 Religion, Religionsphilosophie
subject: 230 Theologie, Christentum

description: Letters of Alcuin of York attest that he composed a liturgical book he called a ‘missal’ while he was abbot of St Martin's basilica in Tours. No manuscripts of this missal survive. It has to be recovered from much later sacramentaries copied in Tours, which have been subject to significant subsequent reworking. This article makes a new attempt to draw out the contents of the missal from these later sources, assuming that the later adjustments by others are an equally valid attempt to improve the usability and comprehensiveness of the book as Alcuin's original endeavour. The discovery of fragments of a much earlier sacramentary from Tours in Solothurn Staatsarchiv also makes a significant contribution to the process.
title: Wi4impact #2 – The Potential of Digital Media in Knowledge Transfer
Creators: name: Kuhle, Birte
Publisher: name: GESIS - Leibniz Institute for the Social Sciences
publisherIdentifier: https://ror.org/018afyw53
Year: 2024
Subjects: subject: Blog
subject: Digital Media
subject: Podcast
subject: Research
subject: Science Communication

description: The second part of the Wi4impact blog series explores the potential of digital media in knowledge transfer. Digital transfer media, such as blogs and podcasts, are increasingly used to ensure that research-based knowledge benefits individuals or society. Digital information and communication technologies allow for a simple, fast, and cost-effective dissemination of information and potentially involve various societal groups in scientific discourse. Despite the potential of digital media to enhance the impact of research and science, they can also impede effective knowledge transfer.
description: Der zweite Teil der Wi4impact-Blogreihe diskutiert die Potenziale von digitalen Medien für den Wissenstransfer. Digitale Transfermedien wie Blogs und Podcasts werden zunehmend eingesetzt, um sicherzustellen, dass Individuen und Gesellschaft von forschungsbasiertem Wissen profitieren. Digitale Information- und Kommunikationstechnologien ermöglichen eine einfache, schnelle und kostengünstige Verbreitung von Informationen und beziehen verschiedene gesellschaftliche Gruppen in den wissenschaftlichen Diskurs ein. Trotz des Potenzials digitaler Medien, den Impact von Forschung und Wissenschaft zu stärken, können sie effektiven Wissenstransfer auch hemmen.
description: GESIS Blog
Controllable energy angular spectrum method
Creators: name: Wang, Fan
name: Shimobaba, Tomoyoshi
name: Kakue, Takashi
name: Ito, Tomoyoshi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Image and Video Processing (eess.IV)
subject: Optics (physics.optics)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Physical sciences

description: A controllable energy method, which considers the undersampling issue of the transfer function and valid spectral energy of a source signal, is proposed to implement angular spectrum diffraction calculation in near and far fields. The proposed method provides an optimized frequency boundary $f_{CE}$ within which it always keeps controllable energy to be diffracted. The controllable energy angular spectrum method significantly reduces the number of samples while having the same accuracy as previous angular spectrum methods, implying a higher calculation efficiency. The new perspective of analyzing spectral energy is shown to improve the performance of relevant diffraction calculations.
Sonnenfleckenzeichnung Nr. 15265.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 12.12.1942, erstellt von William Otto Brunner
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1942

description: Bleistiftzeichnung mit Tinte und Farbstift überschrieben, erstellt als Projektionsbildzeichnung in der Eidgenössischen Sternwarte Zürich, später ergänzt mit einer kleinen Tabelle für die Auszählung der Flecken nach ihrer Verteilung auf Abschnitte der sichtbaren Sonnenhälfte, nach Quadrant bzw. nach Halbkugel (N, S, W, E). Instrument: Kern-Merz-Refraktor.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden mit Bleistift auf einem Vordruck eingetragen. Unter Umständen sind Angaben zu Protuberanzen vermerkt