10 research outputs found
Quasi-steady quasi-homogeneous (QSQH) description of the relationship between large-scale and small-scale motions in near-wall turbulence
No full textThe validity of the recently proposed hypothesis that the influence of large-scale motions on the near-wall turbulence is quasisteady is investigated by quantitative comparisons with the data obtained by direct numerical simulations of a turbulent channel flow. Large-scale motions are filtered by a Fourier cut-off filter multi-objectively optimised to increase the correlation between large-scale motions near and away from the wall while decreasing the correlation between small-scale motions. The quasi-steady hypothesis is found to be approximate. It is also found that adding non-linear terms into calculations will improve the accuracy of the prediction
Joule heating in nanowires
No full textWe study the effect of Joule heating from electric currents flowing through ferromagnetic nanowires on the temperature of the nanowires and on the temperature of the substrate on which the nanowires are grown. The spatial current density distribution, the associated heat generation, and diffusion of heat is simulated within the nanowire and the substrate. We study several different nanowire and constriction geometries as well as different substrates: (thin) silicon nitride membranes, (thick) silicon wafers, and (thick) diamond wafers. The spatially resolved increase in temperature as a function of time is computed. For effectively three-dimensional substrates (where the substrate thickness greatly exceeds the nanowire length), we identify three different regimes of heat propagation through the substrate: regime (i), where the nanowire temperature increases approximately logarithmically as a function of time. In this regime, the nanowire temperature is well-described analytically by You et al. [APL89, 222513 (2006)]. We provide an analytical expression for the time tc that marks the upper applicability limit of the You model. After tc, the heat flow enters regime (ii), where the nanowire temperature stays constant while a hemispherical heat front carries the heat away from the wire and into the substrate. As the heat front reaches the boundary of the substrate, regime (iii) is entered where the nanowire and substrate temperature start to increase rapidly. For effectively two-dimensional substrates (where the nanowire length greatly exceeds the substrate thickness), there is only one regime in which the temperature increases logarithmically with time for large times. We provide an analytical expression, valid for all pulse durations, that allows one to accurately compute this temperature increase in the nanowire on thin substrate
Proposal of a micromagnetic standard problem for ferromagnetic resonance simulations
No full textNowadays, micromagnetic simulations are a common tool for studying a wide range of different magnetic phenomena, including the ferromagnetic resonance. A technique for evaluating reliability and validity of different micromagnetic simulation tools is the simulation of proposed standard problems. We propose a new standard problem by providing a detailed specification and analysis of a sufficiently simple problem. By analyzing the magnetization dynamics in a thin permalloy square sample, triggered by a well defined excitation, we obtain the ferromagnetic resonance spectrum and identify the resonance modes via Fourier transform. Simulations are performed using both finite difference and finite element numerical methods, with OOMMF and Nmag simulators, respectively. We report the effects of initial conditions and simulation parameters on the character of the observed resonance modes for this standard problem. We provide detailed instructions and code to assist in using the results for evaluation of new simulator tools, and to help with numerical calculation of ferromagnetic resonance spectra and modes in general
Enhanced spin transfer torque effect for transverse domain walls in cylindrical nanowires
No full textRecent studies have predicted extraordinary properties for transverse domain walls in cylindrical nanowires: zero depinning current, the absence of the Walker breakdown, and applications as domain wall oscillators. In order to reliably control the domain wall motion, it is important to understand how they interact with pinning centers, which may be engineered, for example, through modulations in the nanowire geometry (such as notches or extrusions) or in the magnetic properties of the material. In this paper we study the motion and depinning of transverse domain walls through pinning centers in ferromagnetic cylindrical nanowires. We use (i) magnetic fields and (ii) spin-polarized currents to drive the domain walls along the wire. The pinning centers are modelled as a section of the nanowire which exhibits a uniaxial crystal anisotropy where the anisotropy easy axis and the wire axis enclose a variable angle ?P. Using (i) magnetic fields, we find that the minimum and the maximum fields required to push the domain wall through the pinning center differ by 30%. On the contrary, using (ii) spin-polarized currents, we find variations of a factor 130 between the minimum value of the depinning current density (observed for ?P=0?, i.e., anisotropy axis pointing parallel to the wire axis) and the maximum value (for ?P=90?, i.e., anisotropy axis perpendicular to the wire axis). We study the depinning current density as a function of the height of the energy barrier of the pinning center using numerical and analytical methods. We find that for an industry standard energy barrier of 40 kBT, a depinning current of about 5 ?A (corresponding to a current density of 6×1010 A/m2 in a nanowire of 10 nm diameter) is sufficient to depin the domain wall. We reveal and explain the mechanism that leads to these unusually low depinning currents. One requirement for this depinning mechanism is for the domain wall to be able to rotate around its own axis. With the right barrier design, the spin torque transfer term is acting exactly against the damping in the micromagnetic system, and thus the low current density is sufficient to accumulate enough energy quickly. These key insights may be crucial in furthering the development of novel memory technologies, such as the racetrack memory, that can be controlled through low current densities.<br/
Perspectives from twenty-two countries on the legal environment for selection.
No full text(from the chapter) To compare and contrast the legal environment for personnel selection in various countries, the senior author prepared a set of questions about the legal environment for selection, prepared model answers describing the legal environment in the United States, and contacted psychologists in various countries, asking them to prepare a document responding to each question and describing the legal environment in their country. They were also invited to suggest additional project participants in other countries. Some invitees declined; some initially agreed, but subsequently did not participate. The goal was to obtain a range of perspectives by sampling about 20 countries, thus, this is by no means a complete catalog of the legal environment around the world. Researchers and practitioners who are experts on the topic of selection participated from 22 countries
Переклад і переспів як форми міжлітературної взаємодії (на матеріалі українськомовного перевтілення балад Р. Бернза)
No full textThe concept of artistic translation, and the criteria for its requirements, are constantly evolving: what used to be considered a translation, now, based on a vastly expanded range of forms of inter-artistic interaction and intertextuality, qualifies translation, as a rehash process, as imitation, motifs’ creation, stylisation, adaptation, transplantation, borrowing, processing, citation, figurative analogy, reminiscence. Mixing them sometimes leads to arbitrary interpretations of the translation freedom degree.
Ideally, the translator should know perfectly, in addition to his native language, the language and culture of the people whose literature they are working on to be congenial to the author of the original to create not only in a rational but also in an emotional register, with complete spiritual dedication. Such was the master of Ukrainian translation Mykola Lukash, who could perfectly harmonise antinomies of spirit/letter, content/form, and more. Entirely original are his transformations of Robert Burn’s ballads.
The author compares the versions of the interpretation of R. Burn’s ballad “My Heart’s in the Highlands” by P. Grabovsky, V. Mysyk, S. Karavanskyi, V. Chernyshenko, M. Lukash, and concludes that the freest and melodic one is the rehash attempt by M. Lukash. This is probably the most related to folk motifs variation on the famous work of Robert Burns.
The ballad “The Lass that Made the Bed for Me” is the most popular in today’s media space. Ever since the Soviet times, the translation of this ballad, made by Samuel Marshak, is still considered a classic one in the trade of translation, where both the substantive and formal parameters of the original are pretty accurately reproduced.
While interpreting this ballad, Mykola Lukash also gives another name – “Adventure” – and chooses not to translate but to rehash it, without distorting the spirit of the original and, at the same time, adapting it to the mental spirit of the target audience. A masterpiece by Robert Burns, retaining the plot twists and psychological nuances Lukash re-chanted it not in the original’s lyrical size, but on the motif of the Ukrainian folk song “Oh, a girl went to pick up mushrooms” [Oѳj divchyѳ na poѳ hrybyѳ khodyѳ la]. This is evidenced not only by the rhythmic-melodic coherence but also by the lexical matches
Erratum to: Observation of the B+ → Jψη′K+ decay
No full textIn the original article, information related to the author list has been corrected. The originally published wrong file has been replaced online
Erratum to: Observation of the B + → Jψη ′ K + decay (Journal of High Energy Physics, (2023), 2023, 8, (174), 10.1007/JHEP08(2023)174)
No full textIn the original article, information related to the author list has been corrected. The originally published wrong fle has been replaced online
Openness to Experience: Its Lower Level Structure, Measurement, and Cross-Cultural Equivalence
No full textOpenness to Experience is an important but relatively poorly understood personality construct. Advances in openness research require further construct clarification as well as establishment of a common framework for conceptualizing and measuring the lower level structure of the construct. In this article, we present data from 3 studies to address this research need. In Study 1, we identify 6 facets of Openness to Experience—intellectual efficiency, ingenuity, curiosity, aesthetics, tolerance, and depth—based on a factor analysis of 36 existing Openness-related scales. In Study 2, we present further validity evidence for the 6-facet structure based on a newly developed measure of Openness. Data from this study also suggest the presence of 2 intermediate-level factors (i.e., aspects) of Openness: intellect and culture. In Study 3, we present a short form of the newly developed measure, retaining items that showed the highest internal consistency and measurement invariance across 3 samples: U.S. undergraduates, Chinese MBA students, and Chinese undergraduates. Together these 3 studies offer a more nuanced understanding of the multifaceted nature of the Openness construct
Publisher Erratum: Long-lived particle reconstruction downstream of the LHCb magnet (Eur. Phys. J. C, (2025), 85, (7), 10.1140/epjc/s10052-024-13686-6)
No full textThe original HTML-version of this article was revised. A number of typographical and editorial details were incorrectly implemented, and the Data and Code Availability Statements were wrongly given. In the abstract, line 11, the Λ symbol was boldfaced while it should have been. In page 1 there were two instances of the symbol “PP”, towards the end of the left column and the beginning of the right column, which should have been “pp”, without capitalization. At the beginning of Section 3, end of page 2 and beginning of page 3, the paragraph starting as “First, Long tracks..” and finishing with “muon chambers” was with indentation, and should not have been. In addition, it was starting as a new paragraph while it should have been started right after “in Fig. 1.”. Moreover, all sentences in this paragraph were starting with a line break while should not be. Overall, the paragraph should read as follows: “..as illustrated in Fig. 1. Long tracks traverse the full tracking system. They include hits in both the VELO and the T1–T3 stations, and optionally in TT (UT in the upgraded detector). Upstream tracks traverse only the VELO and the TT (UT) stations. They are typically produced by low momentum particles, which are bent away by the magnetic field, thus failing to reach the T1–T3 stations. Downstream tracks traverse both the TT (UT) and T1–T3 stations, but do not leave any hit in the VELO. They typically belong to decay products of long-lived particles decaying beyond the VELO, such as Λ or KS0 hadrons. VELO tracks have hits only in the VELO. They include large-angle or backward tracks, useful for the determination of the PV, as well as very low momentum tracks. T tracks have hits only in the T1–T3 stations. Similarly to Downstream tracks, they include the decay products of long-lived particles decaying far away from the PV, up to several metres. A significant fraction of tracks reconstructed in this category comes from secondary interactions with the material of the mechanical structures and back-scattering particles coming from the calorimeters and hadron shield behind the muon chambers.” In page 3, right column, line 13, “layer” should have been “layers”. In page 4, left column, lines 5–6, the J/ψ→μ+μ- decay descriptor was broken in two lines and should have been in a single line. In several places in the HTML-version the Λ and Λb0 particles were written using incorrect fonts, with the Λ symbol boldfaced and the b subscript slanted, while they both should have not been. The text justification in the caption of Figs. 13 and 22 was left and should have been full. Several figure captions used incorrect fonts for denoting the particles, inconsistently with the fonts in the main text. For example, in Fig. 2: π+π- and ψ in J/ψ were slanted and should not be; the subscripts S for KS0 and b for Λb were also slanted and should not be; the Λ symbol denoting the Λ and Λb particles were boldfaced and should not be. Captions of Figs. 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 and 27 are also affected. The Data Availability Statement in page 19 was “Data will be made available on reasonable request. [Author’s comment: The datasets generated during the current study are available from the corresponding author on reasonable request.].” and should have been “The LHCb experiment has agreed to the CERN open data policy summarised in https://opendata.cern.ch/docs/about. In particular, Level 1 data associated with this publication are made available on the CERN document server at http://cds.cern.ch/record/2908392/files/. These data contain material related to the paper that allows a reinterpretation of the results in the context of new theoretical models.” The Code Availability Statement in page 19 was “Code/software cannot be made available for reasons disclosed in the code availability statement. [Author’s comment: The code/software generated during the current study is not publicly available but is available from the corresponding author on reasonable request.].” and should have been “Specific analysis software/code used to produce the results shown in the publication is preserved within the LHCb collaboration internally and can be provided on reasonable request, provided it does not contain information that can be associated with unpublished results.” The original article has been corrected and the publisher apologizes for the inconvenience caused
