cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The clustering of merging star-forming haloes: dust emission as high frequency arcminute CMB foreground
Creators: name: Righi, Mattia
name: Hernandez-Monteagudo, Carlos
name: Sunyaev, Rashid
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Future observations of CMB anisotropies will be able to probe high multipole regions of the angular power spectrum, corresponding to a resolution of a few arcminutes. Dust emission from merging haloes is one of the foregrounds that will affect such very small scales. We estimate the contribution to CMB angular fluctuations from objects that are bright in the sub-millimeter band due to intense star formation bursts following merging episodes. We base our approach on the Lacey-Cole merger model and on the Kennicutt relation which connects the star formation rate in galaxies with their infrared luminosity. We set the free parameters of the model in order to not exceed the SCUBA source counts, the Madau plot of star formation rate in the universe and COBE/FIRAS data on the intensity of the sub-millimeter cosmic background radiation. We show that the angular power spectrum arising from the distribution of such star-forming haloes will be one of the most significant foregrounds in the high frequency channels of future CMB experiments, such as PLANCK, ACT and SPT. The correlation term, due to the clustering of multiple haloes at redshift z~2-6, is dominant in the broad range of angular scales 200
description: 18 pages, 16 figures. Accepted by Astronomy & Astrophysics
VP12-14: A Flux Reversal Motor with Halbach Array Magnets Inserted into Stator Teeth
Creators: Han Chen
Feng Xiao
Yi Du
Xiaoyong Zhu
Yi Mao
Publisher: name: IEEE
Year: 2023

Sensors, High Frequency Devices, and Power Devices (Virtual)
Flux reversal motors (FRMs) have the merits of simple structure and easy heat dissipation [1]. In this paper, a novel FRM with Halbach array magnets inserted into the stator teeth is proposed. The topology of the proposed motor as well as its working principle is presented based on flux modulation theory. Meanwhile, the electromagnetic performances are comprehensively compared with the conventional surface-mounted permanent magnet (PM) FRMs. The results reveal that the proposed FRM has superior electromagnetic performances than the conventional one, which attributes to flux focusing effect of Halbach array magnets and the reduced equivalent airgap length. Fig. 1 shows two 12-slot/17-pole FRM topologies, both of which are consisted of doubly-salient laminations and three-phase concentrated windings, but the number, location and magnetized direction of PMs are different. For the conventional FRM (C-FRM), two radial magnetized PMs are surface-mounted on each stator tooth, and two PMs adjacent to a stator slot opening have opposite polarity. However, For the proposed FRM, a Halbach magnets array consisting of three magnets is inserted into each stator tooth, in which the middle PM is radial magnetized and PMs on the two sides are circumferentially magnetized in opposite directions. The proposed FRM is compared with the conventional FRM in terms of back electromotive force (EMF), self-inductance, average torque, overload capability and so on. It should be noted that two motors have been both optimized in conditions of the same stator outer diameter, stack length, airgap length, PMs usage, and copper loss. As shown in Fig. 2, the fundamental amplitude of back EMF (Em1) and average torque (Tav) of the proposed FRM are 2 and 1.6 times those of the conventional FRM, respectively. Although the proposed FRM has a larger torque ripple (Tr) than its conventional counterpart, the difference is generally small. Moreover, other electromagnetic performance comparisons will be presented in the full paper.References: [1] H. Hua, Z. Q. Zhu, IEEE Trans. Energy Convers., vol. 37, no. 3, pp. 1815–1824 (2022).
Biased random walks on combs
Creators: name: Elliott, Tanya M
name: Wheater, John F
Publisher: name: arXiv
Year: 2007
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We develop rigorous, analytic techniques to study the behaviour of biased random walks on combs. This enables us to calculate exactly the spectral dimension of random comb ensembles for any bias scenario in the teeth or spine. Two specific examples of random comb ensembles are discussed; the random comb with nonzero probability of an infinitely long tooth at each vertex on the spine and the random comb with a power law distribution of tooth lengths. We also analyze transport properties along the spine for these probability measures.
description: minor changes in technical definitions
Charged strange star in $f(R,T)$ gravity with linear equation of state
Creators: name: Rej, Pramit
name: Bhar, Piyali
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Our present study involves the strange stars model in the framework of $f(R,T)$ theory of gravitation. We have taken a linear function of the Ricci scalar $R$ and the trace $T$ of the stress-energy tensor $T_{μν}$ for the expression of $f(R,T)$, i.e., $f(R,T)=R+ 2 γT $ to obtain the proposed model, where $γ$ is a coupling constant. Moreover, to solve the hydrostatic equilibrium equations, we consider a linear equation of state between the radial pressure $p_r$ and matter density $ρ$ as $p_r=αρ-β$, where $α$ and $β$ are some positive constants, Both $α,\,β$ depend on coupling constant $γ$ which have been also depicted in this paper. By employing the Krori-Barua {\em ansatz} already reported in the literature [J. Phys. A, Math. Gen. 8:508, 1975] we have found the solutions of the field equations in $f (R, T )$ gravity. The effect of coupling constant $γ$ have been studied on the model parameters like density, pressures, anisotropic factor, compactness, surface redshift, etc. both numerically and graphically. A suitable range for $γ$ is also obtained. The physical acceptability and stability of the stellar system have been tested by different physical tests, e.g., the causality condition, Herrera cracking concept, relativistic adiabatic index, energy conditions, etc. One can regain the solutions in Einstein gravity when $γ\rightarrow 0$
description: 26 Pages, 10 Figures
Schäden durch Mikroorganismen
Creators: name: Eimer, Manfred
name: Hörsten, Dieter
Publisher: name: LANDTECHNIK
Year: 1999

description: Pflanzliches Erntegut bietet Mikroorganismen zumeist gute Wachstumsbedingungen, die schnell zu Verlusten und Verderb führen können. Grundlage für technisches Handeln sind Kenntnisse über mikrobielle Entwicklungen und Umsetzungen. Sie ermöglichen Vorgaben für eine zielgerichtete Konservierung und Lagerung.
description: LANDTECHNIK, Bd. 54 Nr. 2 (1999)
Neutrino Mass Hierarchy and Stepwise Spectral Swapping of Supernova Neutrino Flavors
Creators: name: Duan, Huaiyu
name: Fuller, George M.
name: Carlson, J.
name: Qian, Yong-Zhong
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We examine a phenomenon recently predicted by numerical simulations of supernova neutrino flavor evolution: the swapping of supernova $ν_e$ and $ν_{μ,τ}$ energy spectra below (above) energy $\EC$ for the normal (inverted) neutrino mass hierarchy. We present the results of large-scale numerical calculations which show that in the normal neutrino mass hierarchy case, $\EC$ decreases as the assumed $ν_e\rightleftharpoonsν_{μ,τ}$ effective $2\times 2$ vacuum mixing angle ($\simeq θ_{1 3}$) is decreased. However, these calculations also indicate that $\EC$ is essentially independent of the vacuum mixing angle in the inverted neutrino mass hierarchy case. With a good neutrino signal from a future Galactic supernova, the above results could be used to determine the neutrino mass hierarchy even if $θ_{13}$ is too small to be detected in terrestrial neutrino oscillation experiments.
description: 4 pages, 2 figures. Version accepted by PRL
Kreisplattentest
Creators: name: Beckmann, Andreas
Publisher: name: LANDTECHNIK
Year: 1999

description: Ein Ziel der Lein-Forschung ist die Produktion einer qualitativ hochwertigen Faser für die Industrie. Für eine möglichst hohe Wertschöpfung ist die Wiederfindung der Faserqualität im Endprodukt von besonderem Interesse. Demzufolge besteht auch ein Bedarf an Prüfmethoden für leinfaserverstärkte Kunststoff, einem der zukunftsträchtigsten Anwendungsgebiete von technisch nutzbaren Naturfasern. Es wird ein neues Prüfverfahren vorgestellt, bei dem eine frei aufliegende Kreisplatte mit einer zentralsymmetrischen Kraft belastet wird. Dieser quasistatische Kreisplattentest wurde sowohl mit der DIN-Zugprüfung als auch mit der DIN-3-Punkt-Biegeprüfung verglichen.
description: LANDTECHNIK, Bd. 54 Nr. 2 (1999)
Intricate Knots in Proteins: Function and Evolution
Creators: name: Virnau, Peter
name: Mirny, Leonid A.
name: Kardar, Mehran
Publisher: name: arXiv
Year: 2007
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Biomolecules (q-bio.BM)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: A number of recently discovered protein structures incorporate a rather unexpected structural feature: a knot in the polypeptide backbone. These knots are extremely rare, but their occurrence is likely connected to protein function in as yet unexplored fashion. Our analysis of the complete Protein Data Bank reveals several new knots which, along with previously discovered ones, can shed light on such connections. In particular, we identify the most complex knot discovered to date in human ubiquitin hydrolase, and suggest that its entangled topology protects it against unfolding and degradation by the proteasome. Knots in proteins are typically preserved across species and sometimes even across kingdoms. However, we also identify a knot which only appears in some transcarbamylases while being absent in homologous proteins of similar structure. The emergence of the knot is accompanied by a shift in the enzymatic function of the protein. We suggest that the simple insertion of a short DNA fragment into the gene may suffice to turn an unknotted into a knotted structure in this protein.
description: 6 pages, 2 figures, 1 table
Domestic Water Displays in the Late Roman West
Creators: name: Wheeler, Ginny
Publisher: name: University of Bern
publisherIdentifier: https://ror.org/02k7v4d05
publisherIdentifierScheme: ROR
Year: 2022
Subjects: late antiquity
Roman fountains
late antique urbanism
late antique villas
water features
Italy
Hispania

description: Catalog of domestic water features that were newly built or renovated in the western Roman Empire between the 3rd and 6th centuries AD.
The 10 parsec sample in the Gaia era
Creators: name: Reylé, Céline
name: Jardine, Kevin
name: Fouqué, Pascal
name: Caballero, Jose A.
name: Smart, Richard L.
name: Sozzetti, Alessandro
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The nearest stars provide a fundamental constraint for our understanding of stellar physics and the Galaxy. The nearby sample serves as an anchor where all objects can be seen and understood with precise data. This work is triggered by the most recent data release of the astrometric space mission Gaia and uses its unprecedented high precision parallax measurements to review the census of objects within 10 pc. The first aim of this work was to compile all stars and brown dwarfs within 10 pc observable by Gaia, and compare it with the Gaia Catalogue of Nearby Stars as a quality assurance test. We complement the list to get a full 10 pc census, including bright stars, brown dwarfs, and exoplanets. We started our compilation from a query on all objects with a parallax larger than 100 mas using SIMBAD. We completed the census by adding companions, brown dwarfs with recent parallax measurements not in SIMBAD yet, and vetted exoplanets. The compilation combines astrometry and photometry from the recent Gaia Early Data Release 3 with literature magnitudes, spectral types and line-of-sight velocities. We give a description of the astrophysical content of the 10 pc sample. We find a multiplicity frequency of around 28%. Among the stars and brown dwarfs, we estimate that around 61% are M stars and more than half of the M stars are within the range M3.0 V to M5.0 V. We give an overview of the brown dwarfs and exoplanets that should be detected in the next Gaia data releases along with future developments. We provide a catalogue of 540 stars, brown dwarfs, and exoplanets in 339 systems, within 10 pc from the Sun. This list is as volume-complete as possible from current knowledge and provides benchmark stars that can be used, for instance, to define calibration samples and to test the quality of the forthcoming Gaia releases. It also has a strong outreach potential.
description: Revised version. Accepted for publication in A&A. 15 pages, 3 figures. The catalogue will be only available in electronic form at https://gruze.org/10pc/, at https://gucds.inaf.it/, and at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/
VP12-13: A Pole-changing Double-side Flux Modulation Permanent Magnet Motor
Creators: Zhuofan He
Feng Xiao
Yi Du
Xiaoyong Zhu
Yi Mao
Publisher: name: IEEE
Year: 2023

Sensors, High Frequency Devices, and Power Devices (Virtual)
Permanent magnet (PM) flux modulation motors are well-known for high torque density compared with conventional PM motors. In this paper, a novel pole-changing double-side flux modulation permanent magnet motor (PC-DSFMM) is proposed based on a PC-PMVM adopting unevenly split modulation tooth structure [1]. The proposed PC-DSFMM is proven to own a considerably higher torque density than the PC-PMVM before and after PC operation due to the double-side flux modulation effect. The motor configuration of the PC-DSFMM is shown in Fig. 1. A PC-winding is installed in 12 stator slots, on which 18 modulation teeth are equipped, and the numbers of modulation teeth on adjacent stator teeth are 1 and 2, forming an unevenly split modulation tooth structure. 6 pieces of PMs are installed on the stator with the same magnetizing direction. Meanwhile, 17 PMs with the same direction of magnetization as rotor PM are half-embedded in the rotor. The original PC-PMVM and its prototype are also shown in Fig. 1 with surface-mounted PM of 17 pole-pairs equipped on the rotor. The two motors are both optimized and have the same assumption of PM. According to the air-gap field modulation theory [2], a fundamental air-gap PM harmonic component with 17 pole-pairs is generated by the PMs on the rotor in the PC-PMVM, which is modulated by the 18 modulation teeth to generate an air-gap PM harmonic of one pole-pair, working as the main source of torque. In the PC-DSFMM, a static air-gap PM harmonic with 18 pole-pairs can be generated by the 6 stator PMs, which interacts with the 17 rotor teeth to increase the amplitudes of the one pole-pair of flux density harmonic. Hence, the torque before and after the PC operation can be increased. The motor performances of the two motors are shown in Table I, where the Mode I and II refer to the motor operation modes before and after PC, respectively. The average torques of PC-DSFMM in Mode I and II are 16.8 and 7.0 Nm, respectively, which are 15.9% and 24.9% higher than those of the PC-PMVM benefitting from the double-side flux modulation effect. Meanwhile, the maximum efficiency, proportion and maximum speed of the high efficiency region (>80%) of PC-DSFMM are slightly smaller than the PC-PMVM.References: [1] Y. Du, Z. He, X. Zhu, etc., A novel pole-changing permanent magnet vernier motor, IEEE Trans. Ind. Electron., vol. 70, no. 6, pp. 6110-6120, (2023). [2] M. Cheng, P. Han, and W. Hua, General airgap field modulation theory for electrical machines, IEEE Trans. Ind. Electron., vol. 64, no. 8, pp. 6063-6073, (2017).
Separation of Liquid Pig Manure
Creators: name: Matzen, Ricard
Publisher: name: LANDTECHNIK
Year: 1999

description: This paper reports the function and warlangresults from a pilotplant in which liquid pig manure was flocculated with Gekobentonite. The supernatant was irrigated an agriculturall and throughout the year,in wintertime, only after ion exchange of ammonium with Agrolith. Earlier Iabaratory research showed that it is possible to purify the liquid to the concentration wanted, although higher puritycosts more. The thicker slurry fraction was stored and treated as ordinary liquid manure. In order to maintain ability for pumping, the treatment was stopped at approximately 12 % dry matter content and it represents a concentration of the liquid manure to approximately one-quarter or one-third of the original volume.
description: LANDTECHNIK, Bd. 54 Nr. 2 (1999)
Additional file 1 of Transcranial magnetic stimulation therapeutic applications on sleep and insomnia: a review
Creators: name: Oroz, Ricardo
name: Kung, Simon
name: Croarkin, Paul E.
name: Cheung, Joseph
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Neuroscience
subject: Physiology
subject: FOS: Biological sciences
subject: Biotechnology
subject: 69999 Biological Sciences not elsewhere classified
subject: Cancer
subject: Science Policy
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Additional file 1: Tables S1 and S2
Star Formation in Galaxies with Large Lower Surface Brightness Disks
Creators: name: O'Neil, K.
name: Oey, S.
name: Bothun, G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present B, R, and Halpha imaging data of 19 large disk galaxies whose properties are intermediate between classical low surface brightness galaxies and ordinary high surface brightness galaxies. We use data taken from the Lowell 1.8m Perkins telescope to determine the galaxies' overall morphology, color, and star formation properties. Morphologically, the galaxies range from Sb through Irr and include galaxies with and without nuclear bars. The colors of the galaxies vary from B-R = 0.3 - 1.9, and most show at least a slight bluing of the colors with increasing radius. The Halpha images of these galaxies show an average star formation rate lower than is found for similar samples with higher surface brightness disks. Additionally, the galaxies studied have both higher gas mass-to-luminosity and diffuse Halpha emission than is found in higher surface brightness samples.
description: 50 pages; Full paper with all figures available at http://www.gb.nrao.edu/~koneil; Accepted by AJ
VP12-09: Design and Investigation of hybrid-tooth dual-winding vernier permanent magnet motor with improved torque performances
Creators: Wu Shan
Deyang Fan
Xiaoyong Zhu
Zixuan Xiang
Li Quan
Publisher: name: IEEE
Year: 2023

Sensors, High Frequency Devices, and Power Devices (Virtual)
Recently, split-tooth vernier permanent magnet (ST-VPM) motors have attracted considerable attention, due to their inherent advantages of high torque density [1]. In this kind of motors, owing to the split-tooth stator structure, motor end winding is reduced, so decreased motor loss and increased efficiency can be realized [2]. However, the split-tooth structure often results in unavoidable flux leakage and magnetic saturation, which limit further enhancement of torque performances. Thus, it has been a hot but challenging issue on how to further improve torque performances of ST-VPM motors. In this paper, a hybrid-tooth dual-winding vernier permanent magnet (HTDW-VPM) motor structure is proposed. The contribution of the proposed motor is presented as follows. Firstly, design principle of hybrid-tooth, which includes split-tooth and straight-tooth, is introduced, which reduces flux leakage and improves torque. In addition, with the assistance of the dual-winding configuration, flux harmonics of different pole pairs can be utilized to contribute to motor output torque. Furthermore, by the purposeful control of inner and outer windings, HTDW-VPM motor can operate during operation modes, which lays a foundation for multi-mode operation. Fig. 1(a) illustrates the structures of the proposed HTDW-VPM motor and the referenced ST-VPM motor. Fig. 1(b) compares the air gap magnetic density and corresponding harmonics distributions. It is observed that the amplitudes of key airgap flux harmonics of the proposed HTDW-VPM motor are higher than the referenced ST-VPM motor. To improve the torque performances of the HTDW-VPM motor, influences of the pole shoe width of both split-tooth and straight tooth are investigated based on the response surface method, as shown in Fig. 1(c). Fig. 2(a) presents flux density and magnetic density distributions of two motors. Fig. 2(b) demonstrates the electromagnetic performance of the two motors under both no-load and load conditions. It is indicated that motor torque is increased by 14.1% and torque ripple is reduced by 71.8% which verifies the reasonability of the proposed HTDW-VPM motor. More simulation and experimental results will be presented in the full paper.References: [1] H. Qu and Z. Q. Zhu, "Analysis of Split-Tooth Stator Slot PM Machine," IEEE Transactions on Industrial Electronics, vol. 68, no. 11, pp. 10580-10591, Nov. 2021, doi: 10.1109/TIE.2020.3031535. [2] L. Fang, D. Li, X. Ren, and R. Qu, "A Novel Permanent Magnet Vernier Machine With Coding-Shaped Tooth," IEEE Transactions on Industrial Electronics, vol. 69, no. 6, pp. 6058-6068, June 2022, doi: 10.1109/TIE.2021.3088331.
Conformal properties of four-gluon planar amplitudes and Wilson loops
Creators: name: Drummond, J. M.
name: Korchemsky, G. P.
name: Sokatchev, E.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present further evidence for a dual conformal symmetry in the four-gluon planar scattering amplitude in N=4 SYM. We show that all the momentum integrals appearing in the perturbative on-shell calculations up to five loops are dual to true conformal integrals, well defined off shell. Assuming that the complete off-shell amplitude has this dual conformal symmetry and using the basic properties of factorization of infrared divergences, we derive the special form of the finite remainder previously found at weak coupling and recently reproduced at strong coupling by AdS/CFT. We show that the same finite term appears in a weak coupling calculation of a Wilson loop whose contour consists of four light-like segments associated with the gluon momenta. We also demonstrate that, due to the special form of the finite remainder, the asymptotic Regge limit of the four-gluon amplitude coincides with the exact expression evaluated for arbitrary values of the Mandelstam variables.
description: 25 pages, 6 figures; v3: minor corrections, references added
VP9-09: Advanced Hybrid MRAM based Novel GPU Cache System for Graphic Processing with High Efficiency
Creators: Shaopu Han
Yanfeng Jiang
Publisher: name: IEEE
Year: 2023

Magnetoresistance and Associated Effects (Virtual)
Magnetic random access memory (MRAM) technology is being vastly explored in recent years as a viable alternative to static random access memory (SRAM) in Last Level Cache (LLC), L2 cache and even L1 cache [1, 2], with the excellent advantages of non-volatility, low leakage power, high security, high density and scalability [3]. The application of MRAM-based CPU cache systems is increasingly reaching maturity at present. The option of applying MRAM cache to more cutting-edge computing and data processing units is being actively considered. With the rapid development of portable computing devices and users’ demand for high-quality graphics rendering, embedded GPU systems for graphics processing are increasingly turning into a key component of computer architecture to enhance computility. The reinforcement of main memory processing speed is far from catching up with the computational power of GPU [4]. In this way, the cache, located between the GPU computing unit and the main memory, serves a crucial role in data transfer. In this paper, spin transfer torque (STT)-MRAM [5] and spin orbit torque (SOT)-MRAM [6] are utilized in L1 and L2 caches to construct a novel GPU system for highly efficient graphics processing. As shown in Fig.1, a novel architecture for GPU cache systems is proposed, including the equipment of prefetching modules in L2 cache assumed by STT-MRAM to raise cache hit rate and hit latency. A controller design scheme for dynamically configuring the cache capacity is adopted in the L1 cache borne by SOT-MRAM. Meanwhile optimized cache coherency protocols are put forward and applied for better productive graphics processing and bandwidth output. Finally the MRAM-based CPU and GPU fusion design scheme is proposed to provide novel ideas for the future design of computer processing units undertaken by non-volatile magnetic memory. Simulation results demonstrated that the GPU cache system proposed in this paper has significant power savings and processing efficiency. As illustrated in Fig.2, the total power consumed by GPU cache system equipped with MRAM (GPU3) can be economized by up to 47.68%.References: [1] R. Saha, Y. P. Pundir, and P. Kumar Pal, Journal of Magnetism and Magnetic Materials, vol. 551, p. 169161 (2022). [2] F. Oboril, R. Bishnoi and M. Ebrahimi et al., IEEE Trans. Comput.-Aided Des. Integr. Circuits Syst., vol. 34, p. 367–380 (2015). [3] R. Rajaei, M. Fazeli, and M. Tabandeh, IEEE Trans. Magn., vol. 51, p. 1–14 (2015). [4] P. Hijma, S. Heldens and A. Sclocco, et al., ACM Comput. Surv., vol. 55, p. 1–81 (2023). [5] A. Khvalkovskiy, D. Apalkov and S. Watts et al., Journal of Physics D: Applied Physics, vol. 46, p. 074001 (2013). [6] G. Prenat, K. Jabeur and P. Vanhauwaert et al., IEEE Transactions on Multi-Scale Computing Systems, vol. 2, p. 49-60 (2015).
VP13-15: Finite size effect on structural and static magnetic properties of CoFe2O4 nanoparticles
Creators: Prashant Kumar
Sandeep Kumar
Saurabh Pathak
Arjun Singh
Komal Jain
James Partridge
R.P. Pant
 
Publisher: name: IEEE
Year: 2023

Soft Magnetic Materials (Virtual)
This study investigates the effect of particle size on the structural and static magnetic properties of CoFe2O4 magnetic nanoparticles (MNPs). A series of four CoFe2O4 MNPs samples with varying particle sizes were synthesized using the wet chemical co-precipitation method, and their structural and magnetic properties were measured. The results reveal a magnetic transition from superparamagnetic to ferromagnetic behavior with increasing particle size. The maximum exchange bias field (HEB) was observed to be 1184 Oe for particles with a size of 17 nm, while the coercivity was found to be significantly higher (~10 kOe) for smaller particles (8 nm), decreasing with increasing particle size. Interestingly, a non-monotonic behavior in HEB with increasing particle size was observed. Additionally, both negative and positive vertical magnetization shifts were observed in the smaller size particles. The dependence of the exchange bias and vertical shifts on particle size exhibited significant differences, which can be attributed to the presence of weakly and strongly pinned spins at the interface. It is proposed that the exchange bias is primarily influenced by the weakly pinned spins, whereas the vertical shift is affected by the strongly pinned spins. The synthesized CoFe2O4 MNPs hold great potential for applications in data storage and biomedical fields [1-2]. Keywords – MNPs, FM, XRD, VSM, Exchange bias.References: [1.] Yuqiu Qu, Haibin Yang, Nan Yang, Materials Letters 60 (2006) 3548-3552. [2.] P. Kumar, S. Pathak, A. Singh, Nanoscale Adv. (2020),2,19389-1948.
Equilibration of the planar modes of ultracold two dimensional ion crystals in a Penning trap
Creators: name: Tang, Chen
name: Shankar, Athreya
name: Meiser, Dominic
name: Dubin, Daniel H. E.
name: Bollinger, John J.
name: Parker, Scott E.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Planar thermal equilibration is studied using direct numerical simulations of ultracold two-dimensional (2D) ion crystals in a Penning trap with a rotating wall. The large magnetic field of the trap splits the modes that describe in-plane motion of the ions into two branches: High frequency cyclotron modes dominated by kinetic energy and low frequency $\mathbf{E \times B}$ modes dominated by potential energy associated with thermal position displacements. Using an eigenmode analysis we extract the equilibration rate between these two branches as a function of the ratio of the frequencies that characterize the two branches and observe this equilibration rate to be exponentially suppressed as the ratio increases. Under experimental conditions relevant for current work at NIST, the predicted equilibration time is orders of magnitude longer than any relevant experimental timescales. We also study the coupling rate dependence on the thermal temperature and the number of ions. Besides, we show how increasing the rotating wall strength improves crystal stability. These details of in-plane mode dynamics help set the stage for developing strategies to efficiently cool the in-plane modes and improve the performance of single-plane ion crystals for quantum information processing.
Vergleich unterschiedlicher Filtermaterialien für Biofilter
Creators: name: Martinec, Milos
name: Hartung, Eberhard
Publisher: name: LANDTECHNIK
Year: 1999

description: Um den Einfluss des Filtermaterials auf die Höhe des Strömungswiderstandes zu prüfen, wurden Untersuchungen an einem Versuchsbiofilter in halbtechnischem Maßstab durchgeführt. Hierzu wurden vier verschiedene Filtermaterialien bei unterschiedlichen Schütthöhen untersucht. Es zeigten sich deutliche Unterschiede zwischen den Strömungswiderständen der einzelnen Filtermaterialien. Der geringste Strömungswiderstand wurde bei gesiebten Kornpostpellets und der höchste bei Biokompost festgestellt. Durch die Auswahl geeigneter Filtermaterialien sind Biofilter zu optimieren und damit die hohen Betriebskosten zu senken.
description: LANDTECHNIK, Bd. 54 Nr. 2 (1999)
Emissionen aus der Rinderhaltung
Creators: name: Berg, Werner
Publisher: name: LANDTECHNIK
Year: 1999

description: Die ökologischen Auswirkungen landwirtschaftlicher Verfahren sind neben ihren ökonomischen, sozialen und ethologischen Merkmalen ein wesentlicher Aspekt ihrer Bewertung. Eine Charakterisierung der ökologischen Auswirkungen und gezielte Einflussnahme auf sie setzen Kenntnisse über die ursächlich wirkenden Stoffflüsse und Prozesse voraus. Deren Komplexität macht die experimentelle Untersuchung aller potenziellen Konstellationen praktisch unmöglich und verlangt, die realen Vorgänge mithilfe von Modellen abzubilden.
description: LANDTECHNIK, Bd. 54 Nr. 2 (1999)
Digitizing for impact - from pixels to scholarship
Creators: name: Shows, Eric
name: Knutzen, Matt
name: Rubinow, Sara
Publisher: name: Zenodo
Year: 2019

description: To further increase the discoverability, access, and use of the New York Public Library’s collections, digitization offers our patrons manifold possibilities for research and a deep dive into the Library’s encyclopedic holdings. Over the past decade, we have established clear workflows for digitizing research collections at the New York Public Library and are dedicated to building partnerships to explore how transforming collections into a digital form can multiply research impact.

In this presentation, we’ll take a closer look at the digitization life cycle of a single collection, from curatorial request to online publishing and structured data extraction. Along the way, we’ll look at the opportunities for scholarship that arise when research materials have been digitized and become available online through our digital portal.

We’ll discuss recent successes that aid genealogical research and our understanding of the urban landscape and the latent potential in some recently digitized collections and corresponding research implications. We’ll also discuss how feedback from researchers about the rising baseline expectations around collections as data has begun to influence how we think about digitization strategy and how we think about partnering with the scholarly community.
Domain Wall Dynamics near a Quantum Critical Point
Creators: name: Yuan, Shengjun
name: De Raedt, Hans
name: Miyashita, Seiji
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study the real-time domain-wall dynamics near a quantum critical point of the one-dimensional anisotropic ferromagnetic spin 1/2 chain. By numerical simulation, we find the domain wall is dynamically stable in the Heisenberg-Ising model. Near the quantum critical point, the width of the domain wall diverges as $(Δ-1) ^{-1/2}$.
description: to appear in Phys. Rev. B
Electron-beam Floating-zone Refined UCoGe
Creators: name: Avers, K. E.
name: Nguyen, M. D.
name: Scott, J. W.
name: Zimmerman, A. M.
name: Thomas, S. M.
name: Rosa, P. F. S.
name: Bauer, E. D.
name: Thompson, J. D.
name: Halperin, W. P.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The interplay between unconventional superconductivity and quantum critical ferromagnetism in the U-Ge compounds represents an open problem in strongly correlated electron systems. Sample quality can have a strong influence on both of these ordered states in the compound UCoGe, as is true for most unconventional superconductors. We report results of a new approach at UCoGe crystal growth using a floating-zone method with potential for improvements of sample quality and size as compared with traditional means such as Czochralski growth. Single crystals of the ferromagnetic superconductor UCoGe were produced using an ultra-high vacuum electron-beam floating-zone refining technique. Annealed single crystals show well-defined signatures of bulk ferromagnetism and superconductivity at $T_c \sim$2.6 K and $T_s \sim$0.55 K, respectively, in the resistivity and heat capacity. Scanning electron microscopy of samples with different surface treatments shows evidence of an off-stoichiometric uranium rich phase of UCoGe collected in cracks and voids that might be limiting sample quality.
description: 10 pages, 6 figures
The Use of Biomass in Colombia based on experience from CELISE project secondment. The Coffee Case
Creators: name: Wronka, Anita
name: Kowaluk, Grzegorz
Publisher: name: Zenodo
Year: 2025
Subjects: celise
biomass

description: The objective of this elaboration was to summarize the knowledge and experience of Authors (Anita Wronka and Grzegorz Kowaluk) focused on coffee production and the produced biomass conversion gained during the secondment completed in Colombia under the European Union Horizon 2020 research and innovation program Marie Sklodowska-Curie Research and Innovation Staff Exchange specific call project “Sustainable production of cellulose-based products and additives to be used in SMEs and rural areas” CELISE, grant agreement No. 101007733, and to refer that knowledge and experience to the economic, technical and scientific state-of-art background in that field.In the scope of this elaboration, the following issues have been addressed:-    global and local (Colombia) trends regarding coffee harvesting and production-    the authors’ own experience with the coffee plantation in Colombia-    overview of residues generated (e.g., coffee pulp, husk, spent coffee grounds)-    the significance of coffee production in Colombia’s agricultural sector-    the important problem of wastewater from coffee cherry processing-    current practices for coffee biomass residue utilization-    opportunities and future directions
Emergence of the Cotton tensor for describing gravity
Creators: name: Harada, Junpei
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: It is shown that the Cotton tensor can describe the effects of gravity beyond general relativity. Any solution of the Einstein equations with or without the cosmological constant satisfies the field equations described by the Cotton tensor. It implies that the cosmological constant is an integration constant. A vacuum of a theory is represented by the vanishing of the Cotton tensor, rather than the vanishing of the Ricci tensor. An exact Schwarzschild-like solution for a static and spherically symmetric source is discovered. Although the field equations involve the third order of derivative, it is found that they reduce to the second-order differential equations due to a variational principle.
description: 5 pages, 1 figure, accepted for publication as a Letter in PRD, v2: typos corrected
Synergies of THESEUS with the large facilities of the 2030s and guest observer opportunities
Creators: name: Rosati, P.
name: Basa, S.
name: Blain, A. W.
name: Bozzo, E.
name: Branchesi, M.
name: Christensen, L.
name: Ferrara, A.
name: Gomboc, A.
name: O'Brien, P. T.
name: Osborne, J. P.
name: Rossi, A.
name: Schüssler, F.
name: Spurio, M.
name: Stergioulas, N.
name: Stratta, G.
name: Amati, L.
name: Casewell, S.
name: Ciolfi, R.
name: Ghirlanda, G.
name: Grimm, S.
name: Guetta, D.
name: Harms, J.
name: Floc'h, E. Le
name: Longo, F.
name: Maggiore, M.
name: Mereghetti, S.
name: Oganesyan, G.
name: Salvaterra, R.
name: Tanvir, N. R.
name: Turriziani, S.
name: Vergani, S. D.
name: Balman, S.
name: Caruana, J.
name: Erkut, M. H.
name: Guidorzi, G.
name: Frontera, F.
name: Martin-Carrillo, A.
name: Paltani, S.
name: Porquet, D.
name: Sergijenko, O.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The proposed THESEUS mission will vastly expand the capabilities to monitor the high-energy sky, and will exploit large samples of gamma-ray bursts to probe the early Universe back to the first generation of stars, and to advance multi-messenger astrophysics by detecting and localizing the counterparts of gravitational waves and cosmic neutrino sources. The combination and coordination of these activities with multi-wavelength, multi-messenger facilities expected to be operating in the thirties will open new avenues of exploration in many areas of astrophysics, cosmology and fundamental physics, thus adding considerable strength to the overall scientific impact of THESEUS and these facilities. We discuss here a number of these powerful synergies.
description: Revised version after submission to Experimental Astronomy
AD-02: Vision for Unified Micromagnetic Modelling(UMM)
Creators: Hans Fangohr
Martin Lang
Samuel Holt
Swapneel Amit Pathak
Kauser Zulfiqar and Marijan Beg
Publisher: name: IEEE
Year: 2023

Magnetization Dynamics I: Micromagnetics and Modeling
There is a growing number of micromagnetic simulation packages available, including OOMMF, mumax3, Boris, magnum.np, Magpar, Nmag, Finmag and others. A scientist or engineer who wants to use one of them, needs to learn how to express the micromagnetic problem of interest in a "language" such as configuration file, script or GUI-clicks that the simulation software understands. This language varies from software to software. If the researchers needs to use another package - perhaps to run the same study on a GPU instead of a CPU - they need to learn a new language to re-express their (unchanged) micromagnetic problem for the next software. We discuss the vision of providing a unified micromagnetic modelling (UMM) interface with which researchers can express the micromagnetic problem once (top third in figure), and from which multiple simulation packages can be instructed automatically to carry out the actual numerical problem solving (middle third in figure). This can be thought of as a compiler that takes a micromagnetic problem description as source and translates the problem description into configuration files for a simulation package (such as mumax3, OOMMF or others) of the users choice. The advantage of such an approach are: (i) As scientists do not need to familiarize themselves with multiple simulation configuration languages, they can more easily use multiple simulation packages. (ii) Being able to easily change the micromagnetic simulator makes it possible to (a) switch from a tool optimized for GPU usage to a CPU-based tool (if, for example, no GPU is present); (b) compare the results computed with different simulation packages; (c) make use of complementary features of the different simulation packages. With recent updates of Ubermag [1,2], we present a prototype of such a framework. Ubermag provides a unified interface (expressed in Python) from which micromagnetic problems can be solved using OOMMF and mumax3. After the simulation has finished, the results are made available to the researcher for analysis within the Python ecosystem of scientific libraries. We discuss the current state of capabilities and possible future developments. We also discuss challenges associated with the proposed approach.References: [1] Marijan Beg, Martin Lang, Hans Fangohr, Ubermag: Towards more effective micromagnetic workflows, IEEE Transactions on Magnetics 58, 7300205 (2021), http://ubermag.github.io/ [2] Marijan Beg, Ryan A. Pepper, Hans Fangohr, User interfaces for computational science: a domain specific language for OOMMF embedded in Python, AIP Advances 7, 056025 (2017)
VP9-06: Improving the Performance of the Magnetic Tunnel Junction by Optimizing the CoFeB/MgO/CoFeB Stack
Creators: Crina Ghemes
Mihai Tibu
Oana-Georgiana Dragos-Pinzaru
Nicoleta Lupu and Horia Chiriac
Publisher: name: IEEE
Year: 2023

Magnetoresistance and Associated Effects (Virtual)
In this work, we focused on improving the magnetoresistance ratio (MR) in the magnetic tunnel junction (MTJ) structure by investigating the influence of the deposition rate, the thickness of the junction layer, i.e., MgO, and the thickness of the ferromagnetic layers in the CoFeB/MgO/CoFeB stack. Among magnetoresistive devices, MTJ structures exhibit higher magnetoresistance at room temperature [1], making them good candidates for a wide range of applications [2,3]. High performance sensors based on the tunnel magnetoresistance (TMR) effect must have defect-free and smooth junction - the biggest challenge in the fabrication process. Except for the MgO layer obtained by electron beam evaporation, all the other component layers of the MTJ structure were deposited by magnetron sputtering on Si/SiO2 wafers as follows: Ta(5 nm)/Ru(20 nm)/Ta(5 nm)/CoFe(2.5 nm)/IrMn(20 nm)/CoFe(2.5 nm)/Ru(0.85 nm)/CoFeB(y nm)/MgO(x nm)/CoFeB(y nm)/Ta(10 nm), where the thicknesses of MgO and CoFeB were varied (x=1, 1.5, 1.8, 2 and y=1.5, 2, 3, 3.5 nm). Transmission electron microscope (TEM) analysis and atomic force microscope (AFM) measurements of the MgO surface deposited at different rates (0.1, 0.2, and 0.3 Å/s) and different thicknesses, showed that the 1.5 nm MgO deposited at a rate of 0.1 Å/s was smoother and had fewer defects as compared to those deposited in other conditions. Of particular importance for the MTJ structure is the thickness of the ferromagnetic CoFeB layers. For different CoFeB thicknesses, the magnetoresistance curves were obtained by measuring the electrical resistance of the samples as a function of the applied magnetic field. A significant difference was found between the MR ratio of the MTJ structure with a CoFeB layer thickness of 3 nm (MR=44%) and the other thicknesses: 10% at 1.5 nm, 15% at 2 nm, and 32% at 3.5 nm. This proves that the optimization of the deposition conditions and the thickness of the thin films in the CoFeB/MgO/CoFeB stack improve the MR ratio of the MTJ structure. Acknowledgements This work was supported by a grant of the Ministry of Research, Innovation and Digitization, CCCDI - UEFISCDI, project number PN-III-P2-2.1-PED-2021-2739, within PNCDI III.References: [1] Y. Nagamine, H. Maehara and K. Tsunekawa, Appl. Phys. Lett. Vol. 89, p.162507 (2006) [2] N. Maciel, E. Marques and L. Naviner, Sensors, Vol. 20(1), p.121 (2020) [3] Z. Q. Lei, L. Li, G. J. Li and C. W. Leung, J. Appl. Phys. Vol. 111, p.07E505 (2012)
Fractional Quantum Hall Effect in the Second Landau Level
Creators: name: Choi, H. C.
name: Kang, W.
name: Sarma, S. Das
name: Pfeiffer, L. N.
name: West, K. W.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present activation gap measurements of the fractional quantum Hall effect (FQHE) in the second Landau level. Signatures for 14 (5) distinct incompressible FQHE states are seen in a high (low) mobility sample with the enigmatic 5/2 even denominator FQHE having a large activation gap of $\sim$600 ($\sim$300mK) in the high (low) mobility sample. Our measured large relative gaps for 5/2, 7/3, and 8/3 FQHE indicate emergence of exotic FQHE correlations in the second Ladau level, possibly quite different from the well-known lowest Landau level Laughlin correlations. Our measured 5/2 gap is found to be in reasonable agreement with the theoretical gap once finite width and disorder broadening corrections are taken into account.
description: 5 pages, 3 figures