cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Matching Social Issues to Technologies for Civic Tech by Association Rule Mining using Weighted Casual Confidence
Creators: name: Kikuchi, Masato
name: Shiramatsu, Shun
name: Kozakai, Ryota
name: Ozono, Tadachika
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: Databases (cs.DB)
subject: FOS: Computer and information sciences

description: More than 80 civic tech communities in Japan are developing information technology (IT) systems to solve their regional issues. Collaboration among such communities across different regions assists in solving their problems because some groups have limited IT knowledge and experience for this purpose. Our objective is to realize a civic tech matchmaking system to assist such communities in finding better partners with IT experience in their issues. In this study, as the first step toward collaboration, we acquire relevant social issues and information technologies by association rule mining. To meet our challenge, we supply a questionnaire to members of civic tech communities and obtain answers on their faced issues and their available technologies. Subsequently, we match the relevant issues and technologies from the answers. However, most of the issues and technologies in this questionnaire data are infrequent, and there is a significant bias in their occurrence. Here, it is difficult to extract truly relevant issues--technologies combinations with existing interestingness measures. Therefore, we introduce a new measure called weighted casual confidence, and show that our measure is effective for mining relevant issues--technologies pairs.
description: The 20th IEEE/WIC/ACM International Conference on Web Intelligence and Intelligent Agent Technology (WI-IAT'21), Special Track on Social Computing
Solar Design and Installation Training � 101-3: Solar Panels (Slides)
Creators: Shuhui Li
Publisher: name: IEEE
Year: 2023

This webinar will provide fundamental knowledge and guideline on how to conduct solar photovoltaic system design and installation process. This tutorial starts with a brief introduction to electric power systems as well as the clean development of modern electric power systems. Then, the webinar turns to one of the fastest-growing clean energy sectors � Solar Photovoltaic (PV). The webinar aims to provide an easy understanding way, with minimum theoretical involvement, to establish with quick understanding and skills on how to design and install a solar PV system. The topics include solar panels, solar inverters, batteries for solar PV systems, racking of solar panels, PV system design guidelines, PV system installation guide, and testing and troubleshooting. A significant number of practical figures, drawings, videos, and presentation animations will be utilized in the webinar series to build fundamental skills that would speed up trainees to get into the solar industry.
This webinar will provide fundamental knowledge and guideline on how to conduct solar photovoltaic system design and installation process. This tutorial starts with a brief introduction to electric power systems as well as the clean development of modern electric power systems. Then, the webinar turns to one of the fastest-growing clean energy sectors � Solar Photovoltaic (PV). The webinar aims to provide an easy understanding way, with minimum theoretical involvement, to establish with quick understanding and skills on how to design and install a solar PV system. The topics include solar panels, solar inverters, batteries for solar PV systems, racking of solar panels, PV system design guidelines, PV system installation guide, and testing and troubleshooting. A significant number of practical figures, drawings, videos, and presentation animations will be utilized in the webinar series to build fundamental skills that would speed up trainees to get into the solar industry.
Power System Advancements Now Require Electromagnetic Transients Programs (Slides)
Creators: Dennis Woodford
Publisher: name: IEEE
Year: 2023

With the commercial operation of high voltage DC transmission (HVDC) systems starting up in the late 1960�s, studying their impact in the power systems they were imbedded in was a major challenge. The digital load flow and transients� stability programs were only being developed when computers were powerful enough to run them. This being in the late 1960�s and early 1970�s. During this same period, HVDC had to be properly assessed on component based transient network analyzers (TNA). This was a laborious process setting up an HVDC system on a TNA and where a duplicate set of actual controls and protections in actual hardware were essential.
With the commercial operation of high voltage DC transmission (HVDC) systems starting up in the late 1960�s, studying their impact in the power systems they were imbedded in was a major challenge. The digital load flow and transients� stability programs were only being developed when computers were powerful enough to run them. This being in the late 1960�s and early 1970�s. During this same period, HVDC had to be properly assessed on component based transient network analyzers (TNA). This was a laborious process setting up an HVDC system on a TNA and where a duplicate set of actual controls and protections in actual hardware were essential.
A k-NN Method to Classify Rare Astronomical Sources: Photometric Search of Brown Dwarfs with Spitzer/IRAC
Creators: name: Marengo, Massimo
name: Sanchez, Mayly C.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present a statistical method for the photometric search of rare astronomical sources based on the weighted k-NN method. A metric is defined in a multi-dimensional color-magnitude space based only on the photometric properties of template sources and the photometric uncertainties of both templates and data, without the need to define ad-hoc color and magnitude cuts which could bias the search. The metric is defined as a function of two parameters, the number of neighbors k and a threshold distance D_th that can be optimized for maximum selection efficiency and completeness. We apply the method to the search of L and T dwarfs in the Spitzer Extragalactic First Look Survey and the Bootes field of the Spitzer Shallow Survey, as well as to the search of sub-stellar mass companions around nearby stars. With high level of completeness, we confirm the absence of late-T dwarfs detected in at least two bands in the First Look Survey, and only one in the Shallow Survey (previously discovered by Stern et al. 2007). This result is in agreement with the expected statistics for late-T dwarfs. One L/early-T candidate is found in the First Look Survey, and 3 in the Shallow Surveys, currently undergoing follow-up spectroscopic verification. Finally, we discuss the potential for brown dwarf searches with this method in the Spitzer warm mission Exploration Science programs.
description: To Appear on The Astronomical Journal
Curie temperature versus hole concentration in field-effect structures of Ga1-xMnxAs
Creators: name: Nishitani, Y.
name: Chiba, D.
name: Endo, M.
name: Sawicki, M.
name: Matsukura, F.
name: Dietl, T.
name: Ohno, H.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The Curie temperature TC is investigated as a function of the hole concentration p in thin films of ferromagnetic semiconductor (Ga,Mn)As. The magnetic properties are probed by transport measurements and p is varied by the application of an external electric field in a field-effect transistor configuration. It is found that TC is proportional to p^γ, where the exponent γ= 0.19 \pm 0.02 over a wide range of Mn compositions and channel thicknesses. The magnitude of gamma is reproduced by a p-d Zener model taking into account nonuniform hole distribution along the growth direction, determined by interface states and the applied gate electric fields.
description: 8 pages, 7 figures
Topotactic Transition: A Promising Opportunity for Creating New Oxides
Creators: name: Meng, Ziang
name: Yan, Han
name: Qin, Peixin
name: Zhou, Xiaorong
name: Wang, Xiaoning
name: Chen, Hongyu
name: Liu, Li
name: Liu, Zhiqi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Topotactic transition is a structural phase change in a matrix crystal lattice mediated by the ordered loss/gain and rearrangement of atoms, leading to unusual coordination environments and metal atoms with rare valent states. As early as in 1990s, low temperature hydride reduction was utilized to realize the topotactic transition. Since then, topological transformations have been developed via multiple approaches. Especially, the recent discovery of the Ni-based superconductivity in infinite-layer nickelates has greatly boosted the topotactic transition mean to synthesizing new oxides for exploring exotic functional properties. In this review, we have provided a detailed and generalized introduction to oxygen-related topotactic transition. The main body of our review include four parts: the structure-facilitated effects, the mechanism of the topotactic transition, some examples of topotactic transition methods adopted in different metal oxides (V, Mn, Fe, Co, Ni) and the related applications. This work is to provide timely and thorough strategies to successfully realize topotactic transitions for researchers who are eager to create new oxide phases or new oxide materials with desired functions.
description: 48 pages, 23 figures. A review paper in press at Advanced Functional Materials
Solar Design and Installation Training � 101-4: Solar Inverters (Slides)
Creators: Shuhui Li
Publisher: name: IEEE
Year: 2023

This webinar will provide fundamental knowledge and guideline on how to conduct solar photovoltaic system design and installation process. This tutorial starts with a brief introduction to electric power systems as well as the clean development of modern electric power systems. Then, the webinar turns to one of the fastest-growing clean energy sectors � Solar Photovoltaic (PV). The webinar aims to provide an easy understanding way, with minimum theoretical involvement, to establish with quick understanding and skills on how to design and install a solar PV system. The topics include solar panels, solar inverters, batteries for solar PV systems, racking of solar panels, PV system design guidelines, PV system installation guide, and testing and troubleshooting. A significant number of practical figures, drawings, videos, and presentation animations will be utilized in the webinar series to build fundamental skills that would speed up trainees to get into the solar industry.
This webinar will provide fundamental knowledge and guideline on how to conduct solar photovoltaic system design and installation process. This tutorial starts with a brief introduction to electric power systems as well as the clean development of modern electric power systems. Then, the webinar turns to one of the fastest-growing clean energy sectors � Solar Photovoltaic (PV). The webinar aims to provide an easy understanding way, with minimum theoretical involvement, to establish with quick understanding and skills on how to design and install a solar PV system. The topics include solar panels, solar inverters, batteries for solar PV systems, racking of solar panels, PV system design guidelines, PV system installation guide, and testing and troubleshooting. A significant number of practical figures, drawings, videos, and presentation animations will be utilized in the webinar series to build fundamental skills that would speed up trainees to get into the solar industry.
Captured at Millimeter Wavelengths: a Flare from the Classical T Tauri Star DQ Tau
Creators: name: Salter, D. M.
name: Hogerheijde, M. R.
name: Blake, G. A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: For several hours on 2008 April 19 the T Tauri spectroscopic binary DQ Tau was observed to brighten, reaching a maximum detected flux of 468 mJy and likely making it (briefly) the brightest object at 3 mm in the Taurus star-forming region. We present the light curve of a rarely before observed millimeter flare originating in the region around a pre-main-sequence star, and the first from a classical T Tauri star. We discuss the properties and nature of the flaring behavior in the context of pulsed accretion flows (the current picture based largely on studies of this object's optically variable spectrum), as well as magnetospheric re-connection models (a separate theory that predicts millimeter flares for close binaries of high orbital eccentricity). We believe that the flare mechanism is linked to the binary orbit, and therefore periodic. DQ Tau makes a strong case for multi-wavelength follow-up studies, performed in parallel, of future flares to help determine whether magnetospheric and dynamical interactions in a proto-binary system are independent.
description: 4 pages, Accepted for publication in A&A Letters
Geometric limits to geometric optical imaging with infinite, planar, non-absorbing sheets
Creators: name: Courtial, Johannes
Publisher: name: arXiv
Year: 2009
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: New ray-optical elements allow generalized refraction of light rays, but geometry imposes limitations on possible mappings between the positions of an object and its geometric image. Here I study the case of an infinite, planar, non-absorbing sheet that images the entire three-dimensional space. The most general case of such a sheet is equivalent to a thin lens with different object- and image-sided focal lengths. Special cases include ordinary thin lenses, confocal lenslet arrays, and negative refraction with n_2 = -n_1.
description: 10 pages, 1 figure
Microscopic origin of Einstein's field equations and the raison d'être for a positive cosmological constant
Creators: name: Padmanabhan, T.
name: Chakraborty, Sumanta
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In the paradigm of effective field theory, one hierarchically obtains the effective action $\mathcal{A}_{\rm eff}[q, \cdots]$ for some low(er) energy degrees of freedom $q$, by integrating out the high(er) energy degrees of freedom $ξ$, in a path integral, based on an action $\mathcal{A}[q,ξ, \cdots]$. We show how one can integrate out a vector field $v^a$ in an action $\mathcal{A}[Γ,v,\cdots ]$ and obtain an effective action $\mathcal{A}_{\rm eff}[Γ, \cdots]$ which, on variation with respect to the connection $Γ$, leads to the Einstein's field equations and a metric compatible with the connection. The derivation \textit{predicts} a non-zero, positive, \cc, which arises as an integration constant. The Euclidean action $\mathcal{A}[Γ,v, \cdots]$, has an interpretation as the heat density of null surfaces, when translated into the Lorentzian spacetime. The vector field $v^a$ can be interpreted as the Euclidean analogue of the microscopic degrees of freedom hosted by any null surface. Several implications of this approach are discussed.
description: Published Version; 12 pages; Prof. T. Padmanabhan has passed away on 17th September, 2021, while this paper was under review in a journal
RESTAVRATSIYA SAN'ATINI QAYTA TIKLASH: MADANIY ME'ROS VA MADANIY BOYLIKLARNI ASRASHNING DOLZARB MASALALARI
Creators: name: Bo'ronova Oybarchin Habibullo qizi  "Termiz" davlat muzey-qo'riqxonasining rassom-ta'mirlovchisi
Publisher: name: Zenodo
Year: 2025

description: Madaniy me’ros insoniyat tarixining bebaho boyligi bo‘lib, uni asrab-avaylash va kelajak avlodlarga yetkazish har bir jamiyatning muhim vazifalaridan biridir. Restavratsiya sanʼati esa ushbu me'rosning asl holatini saqlab qolish va tiklashda asosiy rol o‘ynaydi. Bugungi kunda restavratsiya jarayonida bir qator dolzarb masalalar mavjud bo‘lib, ularni hal etish madaniy boyliklarni muvaffaqiyatli asrashga xizmat qiladi. Ushbu maqolada, restavratsiya san’atining bugungi kundagi ahamiyati, madaniy me’roslarni, shuningdek madaniy boyliklarni asrashning dolzarb masalalari haqida fikr va mulohazalar qilinadi.

Kalit so‘zlar: restavratsiya san’ati, qayta tiklash jarayoni, madaniy me’ros, tarixiy eksponatlar, milliy qadriyat
AudioDec: An Open-source Streaming High-fidelity Neural Audio Codec
Creators: name: Wu, Yi-Chiao
name: Gebru, Israel D.
name: Marković, Dejan
name: Richard, Alexander
Publisher: name: arXiv
Year: 2023
Subjects: subject: Audio and Speech Processing (eess.AS)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: A good audio codec for live applications such as telecommunication is characterized by three key properties: (1) compression, i.e.\ the bitrate that is required to transmit the signal should be as low as possible; (2) latency, i.e.\ encoding and decoding the signal needs to be fast enough to enable communication without or with only minimal noticeable delay; and (3) reconstruction quality of the signal. In this work, we propose an open-source, streamable, and real-time neural audio codec that achieves strong performance along all three axes: it can reconstruct highly natural sounding 48~kHz speech signals while operating at only 12~kbps and running with less than 6~ms (GPU)/10~ms (CPU) latency. An efficient training paradigm is also demonstrated for developing such neural audio codecs for real-world scenarios. Both objective and subjective evaluations using the VCTK corpus are provided. To sum up, AudioDec is a well-developed plug-and-play benchmark for audio codec applications.
description: 5 pages, 1 figure, 5 tables. Proc. ICASSP, 2023
Comment: Citation Statistics
Creators: name: Hall, Peter Gavin
Publisher: name: arXiv
Year: 2009
Subjects: subject: Methodology (stat.ME)
subject: Digital Libraries (cs.DL)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Comment on "Citation Statistics" [arXiv:0910.3529]
description: Published in at http://dx.doi.org/10.1214/09-STS285D the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Appunti sui brevia di XI e XII secolo
Creators: name: Ansani, Michele
Publisher: name: Scrineum Rivista
Year: 2013
Subjects: diplomatics; medieval documentary sources; brevia; Northern Italy

description: Among the early middle ages documentary heritage, really poor is the quantity of brevia we can examine; but it doesn't mean this kind of record was unusual, as is shown by some formulae of Chartularium langobardicum (10th century). Nevertheless, they begun to frequently appear since mid 11th Century, in order to resolve new claims that changes in politics and social relations brought out (feudal relations as well as, later, legal activity of cities government, and overall extra-judicial settlement of disputes). This survey has the purpose to analyze summarily the phase, between XIth and XIIth Century, in wich recording per breve became a normal option in these circumstances, when a clean pattern was developed by notarial culture - also provided of courts experience - giving breve a form that remind, in some respects, the previous pleas writing schemes.
description: Scrineum Rivista, 4 (2006-2007)
AIBugHunter: A Practical Tool for Predicting, Classifying and Repairing Software Vulnerabilities
Creators: name: Fu, Michael
name: Tantithamthavorn, Chakkrit
name: Le, Trung
name: Kume, Yuki
name: Nguyen, Van
name: Phung, Dinh
name: Grundy, John
Publisher: name: arXiv
Year: 2023
Subjects: subject: Software Engineering (cs.SE)
subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Many ML-based approaches have been proposed to automatically detect, localize, and repair software vulnerabilities. While ML-based methods are more effective than program analysis-based vulnerability analysis tools, few have been integrated into modern IDEs, hindering practical adoption. To bridge this critical gap, we propose AIBugHunter, a novel ML-based software vulnerability analysis tool for C/C++ languages that is integrated into Visual Studio Code. AIBugHunter helps software developers to achieve real-time vulnerability detection, explanation, and repairs during programming. In particular, AIBugHunter scans through developers' source code to (1) locate vulnerabilities, (2) identify vulnerability types, (3) estimate vulnerability severity, and (4) suggest vulnerability repairs. In this article, we propose a novel multi-objective optimization (MOO)-based vulnerability classification approach and a transformer-based estimation approach to help AIBugHunter accurately identify vulnerability types and estimate severity. Our empirical experiments on a large dataset consisting of 188K+ C/C++ functions confirm that our proposed approaches are more accurate than other state-of-the-art baseline methods for vulnerability classification and estimation. Furthermore, we conduct qualitative evaluations including a survey study and a user study to obtain software practitioners' perceptions of our AIBugHunter tool and assess the impact that AIBugHunter may have on developers' productivity in security aspects. Our survey study shows that our AIBugHunter is perceived as useful where 90% of the participants consider adopting our AIBugHunter. Last but not least, our user study shows that our AIBugHunter could possibly enhance developers' productivity in combating cybersecurity issues during software development.
description: 34 pages, Accepted at Empirical Software Engineering Journal
Hot Giant Loop Holography
Creators: name: Grignani, Gianluca
name: Karczmarek, Joanna L.
name: Semenoff, Gordon W.
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We argue that there is a phase transition in the expectation value of the Polyakov loop operator in the large N limit of the high temperature deconfined phase of N=4 Yang-Mills theory on a spatial S^3. It occurs for large completely symmetric representation of the SU(N) symmetry group. We speculate that this transition is reflected in the string theory dual as a critical behavior of the D3-brane duals of large representation loops.
description: 4 pages, 1 figure, final section updated
Quasistationary states in a quantum dot formed at the edge of a topological insulator by magnetic barriers with finite transparency
Creators: name: Khomitsky, D. V.
name: Lavrukhina, E. A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A model of quasistationary states is constructed for the one-dimensional edge states propagating along the edge of a two-dimensional topological insulator based on HgTe/CdTe quantum well in the presence of magnetic barriers with finite transparency. The lifetimes of these quasistationary states are found analytically and numerically via different approaches including the solution of the stationary Schroedinger equation with complex energy and the solution of the transmission problem for a double barrier structure. The results can serve as a guide for determining the parameters of magnetic barriers creating the quantum dots where the lifetimes for the broadened discrete levels are long enough for manipulation with their occupation numbers by external fields.
description: 6 pages, 2 figures, presented at the International Conference PhysicA.SPb/2021, 18-22 October 2021, St Petersburg, Russian Federation (http://physica.spb.ru/)
Develop and evaluate a smart film Tablet from tissue paper that is capable enough to increase the dissolution profile of BCS class-II drug Cilnidipine
Creators: name: Rajeshree M.
Publisher: name: gjrpublication
Year: 2024

description: Newly developed API cilnidipine from BCS class-II which has high permeability and low solubility hence increased solubility by smart film tablet. The main objective of the work was to improve the drug dissolution rate using smart film technology. The smart film technique is a novel approach to overcome poor solubility. The technique uses commercial paper in which cilnidipine drug can be loaded onto the paper, it can be a creative and innovative way to increase the dissolution rate of cilnidipine drug. The tablets appear shiny and with a smooth surface. The pharmaceutical quality was acceptable, i.e. all tablets fulfilled the requirements for tablets. Drug-loaded tablets were produced by compression of drug-loaded paper. Drug loading did not alter the pharmaceutical quality. However, the uncoated tablets possessed an extremely fast disintegration, i.e. intense swelling upon contact with water, which might hamper the swallowing after oral administration. In fact, tablets made from paper are a novel and promising strategy for improved oral drug delivery. They can be easily produced without any further excipients and possess pharmaceutical quantity. These are the different papers like Kitchen roll, disposable handkerchief, coffee filter paper, and envelope paper which are used in preparation of smart film tablet. Tablets were subjected to characterization such as thickness, hardness, friability, weight uniformity, drug content, disintegration time, and In-vitro drug release. The In vitro drug release in optimized formulation T1 was found to be 99.21 % in 5 min and disintegration time was found to be 14 sec.In vitro dissolution results are subjected to statistical analysis and found that the formulation (T1) has shown an increased dissolution rate (99.21% at 5 min), compared to the marketed formulation (36.71%in 5min ).
De la risa a carcajadas al mal ejemplo quijotesco en la novela del XVIII. Don Quijote de la Manchuela
Creators: name: Jurado Santos, Agapita
Publisher: name: Firenze University Press
Year: 2013
Subjects: festive; controversy; mockery; reappraise; bad example

description: Don Quixote rapidly became a huge success. It was translated into several languages and reworked into genres with a festive and theatrical nature. In Spain, during the seventeenth century, its comic side was exploited, which provoked liberating laughter that, in France, led to its association with the satire genre. In the eighteenth century, the novel was considered a minor genre, of no educational value. The century began with a fierce controversy over the meaning of Cervantes’ work, since according to Rapin, some readers would have seen a mockery of the Spanish nobility in the insane gentleman. However, during the eighteenth century the first steps were taken to reappraise Don Quixote due to its acceptance as a classic by the Spanish Royal Academy in 1780. The Academy considered Don Quixote a mocking and didactic hero, a bad example to be avoided. Yet, the work was an important step in the construction of a new genre, the novel. Don Quijote de la Manchuela, by Donato de Arenzana (1767), reflects an attentive reading of Cervantes’ Don Quixote, and special attention to the neoclassical cannon. Therefore it can provide useful information about writers’ interests, in the preromantic eighteenth century.
description: LEA - Lingue e Letterature d'Oriente e d'Occidente, Vol 1 (2012)
Beyond Johnny. un osservatorio per il giardino botanico di Auroville, India, marzo 2007
Creators: name: Barthel, Elena
Publisher: name: Macramè
Year: 2008

description: Diploma 9, from the Architectural Association of London, was invited to finance and build a watch tower for the Botanical Garden of the international city of Auroville, on the east coast of southern India.
Since 1968, groups of people from all around the world, have been building the experimental township. Today the latest challenge is to transfer all the innovation onto an urban scale to create a sustainable development able to answer the global challenge of the new century.
description: Macramè, macramè 2–2008
Intergrain current flow in a randomly oriented polycrystalline SmFeAsO0.85 oxypnictide
Creators: name: Kametani, F.
name: Li, P.
name: Abraimov, D.
name: Polyanskii, A. A.
name: Yamamoto, A.
name: Jiang, J.
name: Hellstrom, E. E.
name: Gurevich, A.
name: Larbalestier, D. C.
name: Ren, Z. A.
name: Yang, J.
name: Dong, X. L.
name: Lu, W.
name: Zhao, Z. X.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We report a direct current transport study of the local intergrain connections in a polycrystalline SmFeAsO0.85 (Sm1111) bulk, for which we earlier estimated significant intergranular critical current density Jc. Our combined low temperature laser scanning microscopy (LTLSM) and scanning electron microscopy observations revealed only few grain-to-grain transport current paths, most of which switched off when a magnetic field was applied. These regions typically occur where current crosses Fe-As, which is a normal-metal wetting-phase that surrounds Sm1111 grains, producing a dense array of superconducting-normal-superconducting contacts. Our study points out the need to reduce the amount of grain boundary-wetting Fe-As phase, as well as the crack density within pnictide grains, as these defects produce a multiply connected current-blocking network.
description: Submitted to Applied Physics Letters
Trame e situazioni
Creators: name: Radicchi, Antonella
Publisher: name: Macramè
Year: 2008

description: Tiny villages, ancient parishes, forgotten churches, working farms, archaeological ruins, old and new paths, neglected public spaces. As a backdrop to these images, are the physical surroundings of the Arno River and the Albano Mountain, which are so beautiful that they take your breath away, grab hold of your eyes, and slow your steps down. So, the project becomes a patchwork quilt sewing together the fabric of the land to create a new system of paths, public spaces and accesses to connect all the villages to the landscape, to highlight the historical importance and to improve the self-sustenance of the land.
description: Macramè, macramè 2–2008
Multi-Instantons and Exact Results III: Unified Description of the Resonances of Even and Odd Anharmonic Oscillators
Creators: name: Jentschura, U. D.
name: Surzhykov, A.
name: Zinn-Justin, J.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: This is the third article in a series of three papers on the resonance energy levels of anharmonic oscillators. Whereas the first two papers mainly dealt with double-well potentials and modifications thereof [see J. Zinn-Justin and U. D. Jentschura, Ann. Phys. (N.Y.) 313 (2004), pp. 197 and 269], we here focus on simple even and odd anharmonic oscillators for arbitrary magnitude and complex phase of the coupling parameter. A unification is achieved by the use of PT-symmetry inspired dispersion relations and generalized quantization conditions that include instanton configurations. Higher-order formulas are provided for the oscillators of degrees 3 to 8, which lead to subleading corrections to the leading factorial growth of the perturbative coefficients describing the resonance energies. Numerical results are provided, and higher-order terms are found to be numerically significant. The resonances are described by generalized expansions involving intertwined non-analytic exponentials, logarithmic terms and power series. Finally, we summarize spectral properties and dispersion relations of anharmonic oscillators, and their interconnections. The purpose is to look at one of the classic problems of quantum theory from a new perspective, through which we gain systematic access to the phenomenologically significant higher-order terms.
description: 51 pages, LaTeX, Latin2 fonts
Design aspects of Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ THz sources: optimization of thermal and radiative properties
Creators: name: Krasnov, Mikhail M.
name: Novikova, Natalia D.
name: Cattaneo, Roger
name: Kalenyuk, Alexey A.
name: Krasnov, Vladimir M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Impedance matching and heat management are important factors influencing performance of THz sources. In this work we analyze thermal and radiative properties of such devices based on mesa structures of a layered high-temperature superconductor Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$. Two types of devices are considered, containing either a conventional large single crystal, or a whisker. We perform numerical simulations for various geometrical configurations and parameters and make a comparison with experimental data for the two types of devices. It is demonstrated that the structure and the geometry of both the superconductor and the electrodes are playing important roles. In crystal-based devices an overlap between the crystal and the electrode leads to appearance of a large parasitic capacitance, which shunts THz emission and prevents impedance matching with open space. The overlap is avoided in whisker-based devices. Furthermore, the whisker and the electrodes form a turnstile (crossed-dipole) antenna facilitating good impedance matching. This leads to more than an order of magnitude enhancement of the radiation power efficiency in whisker-based, compared to crystal-based devices. These results are in good agreement with presented experimental data.
description: Presented at the 12 International Conference on Intrinsic Josephson Effect and Horizons of Superconducting Spintronics (22-25 Sept. 2021, Chisinau, Moldova)
Dispersion relation and spectral function of an impurity in a one-dimensional quantum liquid
Creators: name: Lamacraft, Austen
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We consider the motion of an impurity particle in a general one-dimensional quantum fluid at zero temperature. The dispersion relation $Ω(P)$ of the impurity is strongly affected by interactions with the fluid as the momentum approaches $\pmπ\hbar n, \pm 3π\hbar n, ...$, where $n$ is the density. This behavior is caused by singular $\pm 2π\hbar n$ scattering processes and can be understood by analogy to the Kondo effect, both at strong and weak coupling, with the possibility of a quantum phase transition where $Ω'(\pm πn)$ jumps to zero with increasing coupling. The low energy singularities in the impurity spectral function can be understood on the same footing.
description: Published version
Comparing the Photometric Calibration of DESI Imaging and Gaia Synthetic Photometry
Creators: name: Zhou, Rongpu
name: Dey, Arjun
name: Lang, Dustin
name: Moustakas, John
name: Schlafly, Edward F.
name: Schlegel, David J.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The relative photometric calibration errors in the DESI Legacy Imaging Surveys (LS), which are used for DESI target selection, can leave imprints on the DESI target densities and bias the resulting cosmological measurements. We characterize the LS calibration systematics by comparing the LS stellar photometry with Gaia DR3 synthetic photometry. We find the stellar photometry of LS DR9 and Gaia has an \textsc{rms} difference of 4.7, 3.7, 4.4 mmag in DECam $grz$ bands, respectively, when averaged over an angular scale of 27 arcmin. There are distinct spatial patterns in the photometric offset resembling the Gaia scan patterns (most notably in the synthesized $g$-band) which indicate systematics in the Gaia spectrophotometry, as well as honeycomb patterns due to LS calibration systematics. We also find large and smoothly varying photometric offsets at $\mathrm{Dec}<-29.25^{\circ}$ in LS DR9 which are fixed in DR10.
description: 4 pages, 1 figure; published in Res. Notes AAS. Data and additional figures are available on Zenodo: https://doi.org/10.5281/zenodo.7884447
Multiplicity fluctuations and temperature fluctuations
Creators: name: Wilk, Grzegorz
name: Wlodarczyk, Zbigniew
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We argue that specific fluctuations observed in high-energy nuclear collisions can be attributed to intrinsic fluctuations of temperature of the hadronizing system formed in such processes and therefore can be described by the same nonextensivity parameter $q$ characterizing Tsallis statistics describing such systems (for $q \to 1$ one recovers the usual Boltzmann-Gibbs approach). It means that $|q-1|$, which is a direct measure of temperature fluctuations, can also be expressed by the observed mean multiplicity, $$, and by its variance, $Var(N)$. This allows to deduce from the experimental data the system size dependence of parameter $q$ with $q = 1$ corresponding to an infinite, thermalized source with a fixed temperature, and with the observed $q > 1$ corresponding to a finite source in which both the temperature and energy fluctuate.
description: Presented at XXX ISMD 2009, to be published in the Int. J. Nonlinear Phenomena in Complex Systems
Causality between investor sentiment and the shares return on the Moroccan and Tunisian financial markets
Creators: name: Mounira, Chniguir
name: Eddine, Henchiri Jamel
Publisher: name: arXiv
Year: 2023
Subjects: subject: Portfolio Management (q-fin.PM)
subject: General Finance (q-fin.GN)
subject: Statistical Finance (q-fin.ST)
subject: FOS: Economics and business

description: This paper aims to test the relationship between investor sentiment and the profitability of stocks listed on two emergent financial markets, the Moroccan and Tunisian ones. Two indirect measures of investor sentiment are used, SENT and ARMS. These sentiment indicators show that there is an important relationship between the stocks returns and investor sentiment. Indeed, the results of modeling investor sentiment by past observations show that sentiment has weak memory; on the other hand, series of changes in sentiment have significant memory. The results of the Granger causality test between stock return and investor sentiment show us that profitability causes investor sentiment and not the other way around for the two financial markets studied.Thanks to four autoregressive relationships estimated between investor sentiment, change in sentiment, stock return and change in stock return, we find firstly that the returns predict the changes in sentiments which confirms with our hypothesis and secondly, the variation in profitability negatively affects investor sentiment.We conclude that whatever sentiment measure is used there is a positive and significant relationship between investor sentiment and profitability, but sentiment cannot be predicted from our various variables.
description: 15 pages, 16 tables
Interpolating fields of carbon monoxide data using a hybrid statistical-physical model
Creators: name: Malmberg, Anders
name: Arellano, Avelino
name: Edwards, David P.
name: Flyer, Natasha
name: Nychka, Doug
name: Wikle, Christopher
Publisher: name: arXiv
Year: 2009
Subjects: subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: Atmospheric Carbon Monoxide (CO) provides a window on the chemistry of the atmosphere since it is one of few chemical constituents that can be remotely sensed, and it can be used to determine budgets of other greenhouse gases such as ozone and OH radicals. Remote sensing platforms in geostationary Earth orbit will soon provide regional observations of CO at several vertical layers with high spatial and temporal resolution. However, cloudy locations cannot be observed and estimates of the complete CO concentration fields have to be estimated based on the cloud-free observations. The current state-of-the-art solution of this interpolation problem is to combine cloud-free observations with prior information, computed by a deterministic physical model, which might introduce uncertainties that do not derive from data. While sharing features with the physical model, this paper suggests a Bayesian hierarchical model to estimate the complete CO concentration fields. The paper also provides a direct comparison to state-of-the-art methods. To our knowledge, such a model and comparison have not been considered before.
description: Published in at http://dx.doi.org/10.1214/08-AOAS168 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Quantum fields on curved spacetimes and a new look at the Unruh effect
Creators: name: Moschella, Ugo
name: Schaeffer, Richard
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We describe a new viewpoint on canonical quantization of linear fields on a general curved background that encompasses and generalizes the standard treatment of canonical QFT given in textbooks. Our method permits the construction of pure states and mixed stated with the same technique. We apply our scheme to the study of Rindler QFT and we present a new derivation of the Unruh effect based on invariance arguments.
Nematic Anchoring on Carbon Nanotubes
Creators: name: Basu, Rajratan
name: Iannacchione, Germano S.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: A dilute suspension of carbon nanotubes (CNTs) in a nematic liquid crystal (LC) does not disturb the LC director. Due to a strong LC-CNT anchoring energy and structural symmetry matching, CNT long axis follows the director field, possessing enhanced dielectric anisotropy. This strong anchoring energy stabilizes local pseudo-nematic domains, resulting in non-zero dielectric anisotropy in the isotropic phase. These anisotropic domains respond to external electric fields and show intrinsic frequency response. The presence of these domains makes the isotropic phase field-responsive, giving rise to a large dielectric hysteresis effect.
description: 3 Pages
Self-Energy Correction to the Bound-Electron g Factor of P States
Creators: name: Jentschura, U. D.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: The radiative self-energy correction to the bound-electron g factor of 2P_1/2 and 2P_3/2 states in one-electron ions is evaluated to order alpha (Z alpha)^2. The contribution of high-energy virtual photons is treated by means of an effective Dirac equation, and the result is verified by an approach based on long-wavelength quantum electrodynamics. The contribution of low-energy virtual photons is calculated both in the velocity and in the length gauge and gauge invariance is verified explicitly. The results compare favorably to recently available numerical data for hydrogenlike systems with low nuclear charge numbers.
description: 8 pages, RevTeX
DEFINITION OF FIQH SCIENCE AND ITS BRIEF HISTORY
Creators: name: Ro'zmetov, Muhammad Mustafo
Publisher: name: Zenodo
Year: 2024

description: Undoubtedly, the science of jurisprudence is one of the necessary sciences that a Muslim must learn. Because this knowledge includes rulings on the circumstances of a person from birth to death. This article describes popular definitions of this science and its brief history.
Multi-spacecraft observations of the structure of the sheath of an interplanetary coronal mass ejection and related energetic ion enhancement
Creators: name: Kilpua, E. K. J.
name: Good, S. W.
name: Dresing, N.
name: Vainio, R.
name: Davies, E. E.
name: Forsyth, R. J.
name: Gieseler, J.
name: Lavraud, B.
name: Asvestari, E.
name: Morosan, D. E.
name: Pomoell, J.
name: Price, D. J.
name: Heyner, D.
name: Horbury, T. S.
name: Angelini, V.
name: O'Brien, H.
name: Evans, V.
name: Rodriguez-Pacheco, J.
name: Herrero, R. Gómez
name: Ho, G. C.
name: Wimmer-Schweingruber, R.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Space Physics (physics.space-ph)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Sheaths ahead of coronal mass ejections (CMEs) are large heliospheric structures that form with CME expansion and propagation. Turbulent and compressed sheaths contribute to the acceleration of particles in the corona and in interplanetary space, but the relation of their internal structures to particle energization is still relatively little studied. In particular, the role of sheaths in accelerating particles when the shock Mach number is low is a significant open problem. This work seeks to provide new insights on the internal structure of CME sheaths with regard to energetic particle enhancements. A good opportunity to achieve this aim was provided by observations of a sheath made by radially aligned spacecraft at 0.8 and $\sim$ 1 AU (Solar Orbiter, Wind, ACE and BepiColombo) on 19-21 April 2020. The sheath was preceded by a weak shock. Energetic ion enhancements occurred at different locations within the sheath structure at Solar Orbiter and L1. Magnetic fluctuation amplitudes at inertial-range scales increased in the sheath relative to the upstream wind. However, when normalised to the local mean field, fluctuation amplitudes did not increase significantly; magnetic compressibility of fluctuation also did not increase. Various substructures were embedded within the sheath at the different spacecraft, including multiple heliospheric current sheet (HCS) crossings and a small-scale flux rope. At L1, the ion flux enhancement was associated with the HCS crossings, while at Solar Orbiter, the enhancement occurred within the rope. Substructures that are swept from the upstream solar wind and compressed in the sheath can act as particularly effective acceleration sites. A possible acceleration mechanism is betatron acceleration associated with the small-scale flux rope and the warped HCS in the sheath.
description: 14 pages, 12 figures; published in Astronomy & Astrophysics, Solar Orbiter First Results (Cruise Phase) special issue
Models and van Kampen theorems for directed homotopy theory
Creators: name: Bubenik, Peter
Publisher: name: arXiv
Year: 2008
Subjects: subject: Algebraic Topology (math.AT)
subject: FOS: Mathematics
subject: 55P99, 68Q85, 18A40, 18A30, 55U99

description: We study topological spaces with a distinguished set of paths, called directed paths. Since these directed paths are generally not reversible, the directed homotopy classes of directed paths do not assemble into a groupoid, and there is no direct analog of the fundamental group. However, they do assemble into a category, called the fundamental category. We define models of the fundamental category, such as the fundamental bipartite graph, and minimal extremal models which are shown to generalize the fundamental group. In addition, we prove van Kampen theorems for subcategories, retracts, and models of the fundamental category.
description: 20 pages, 10 figures