cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Improved action and path synthesis using gradient sampling
Creators: name: Traft, Neil
Publisher: name: University of British Columbia
Year: 2017

description: An autonomous or semi-autonomous powered wheelchair would bring the benefits of increased mobility and independence to a large population of cognitively impaired older adults who are not currently able to operate traditional powered wheelchairs. Algorithms for navigation of such wheelchairs are particularly challenging due to the unstructured, dynamic environments older adults navigate in their daily lives. Another set of challenges is found in the strict requirements for safety and comfort of such platforms. We aim to address the requirements of safe, smooth, and fast control with a version of the gradient sampling optimization algorithm of [Burke, Lewis & Overton, 2005]. We suggest that the uncertainty arising from such complex environments be tracked using a particle filter, and we propose the Gradient Sampling with Particle Filter (GSPF) algorithm, which uses the particles as the locations in which to sample the gradient. At each step, the GSPF efficiently finds a consensus direction suitable for all particles or identifies the type of stationary point on which it is stuck. If the stationary point is a minimum, the system has reached its goal (to within the limits of the state uncertainty) and the algorithm naturally terminates; otherwise, we propose two approaches to find a suitable descent direction. We illustrate the effectiveness of the GSPF on several examples with a holonomic robot, using the Robot Operating System (ROS) and Gazebo robot simulation environment, and also briefly demonstrate its extension to use a version of the RRT* planner instead of a value function.
Positioning in a flat two-dimensional space-time: the delay master equation
Creators: name: Coll, Bartolomé
name: Ferrando, Joan Josep
name: Morales-Lladosa, Juan Antonio
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The basic theory on relativistic positioning systems in a two-dimensional space-time has been presented in two previous papers [Phys. Rev. D {\bf 73}, 084017 (2006); {\bf 74}, 104003 (2006)], where the possibility of making relativistic gravimetry with these systems has been analyzed by considering specific examples. Here we study generic relativistic positioning systems in the Minkowski plane. We analyze the information that can be obtained from the data received by a user of the positioning system. We show that the accelerations of the emitters and of the user along their trajectories are determined by the sole knowledge of the emitter positioning data and of the acceleration of only one of the emitters. Moreover, as a consequence of the so called master delay equation, the knowledge of this acceleration is only required during an echo interval, i.e., the interval between the emission time of a signal by an emitter and its reception time after being reflected by the other emitter. We illustrate these results with the obtention of the dynamics of the emitters and of the user from specific sets of data received by the user.
description: 15 pages, 6 figures
Synthese und strukturelle Charakterisierung von bcpm-Metallcarbonyl-Dimeren (bcpm = Biscyclopentadienylmethan) mit Metallen der 6. Nebengruppe ( = SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF BCPM-METAL-CARBONYL DIMERS WITH GROUP-VIB METALS (BCPM + BISCYCLOPENTADIENYLMETHANE))
Creators: name: Brunner, Henri
name: Grassl, R.
name: Wachter, Joachim
name: Nuber, B.
name: Ziegler, M. L.
Publisher: name: Universität Regensburg
Year: 1992
Subjects: subject: 540 Chemie

description: The reaction of methylendicyclopentadiene (bcpmH2) with (CH3CN)3M(CO)3 (M = Cr, Mo, W) gives the complexes bcpmM2(CO)6 (1-3) in good yields (47-78%). The synthesis of bCPmMO2(CO)6Cl2 (4) starts from bcpmLi2 and Mo(CO)6. In a one-pot procedure, acidification with CH3CO2H and reaction with CCl4 give 4 in 43% yield. Low temperature H-1 NMR investigations of 1 and 2 reveal a dynamic process analogous to that already observed for the silylbridged homologues. The X-ray analysis of 1 proves the chiral structure of the molecule, which is the consequence of the distortion of the bcpm-ligand. The Cr-Cr distance is 3.211(2) angstrom.
Metallocene sulfide chemistry of niobium and tantalum: new insights into the formation of niobium-polysulfido complexes and synthesis, structure, and reactivity of Cp2'Ta(.eta.2-S2)H (Cp' = tert-BuC5H4)
Creators: name: Bach, H. J.
name: Brunner, Henri
name: Wachter, Joachim
name: Kubicki, Marek M.
name: Leblanc, J. C.
name: Moise, C.
name: Volpato, F.
name: Nuber, B.
name: Ziegler, M. L.
Publisher: name: Universität Regensburg
Year: 1992
Subjects: subject: 540 Chemie

description: The previously described reaction of Cp'2NbH3 (Cp' = t-BuC5H4) with S8 was investigated with regard to the kinetic stabilization of as yet elusive intermediates during the formation of the polysulfide complex Cp'4Nb2S9 (1). Therefore, the permethylated complex Cp*2NbS3H (2; Cp* = C5Me5) and the Ta complex Cp'2TaS2H (3) were synthesized in a related reaction and structurally investigated. Despite the problematic localization of the hydride atom during X-ray crystallographic studies, the molecules can be described in a proper manner: Characteristic of 2 and 3 are M(eta(2)-S2) cores to which either an SH (2) or a H (3) ligand is attached. Complex 3 is the first known tantalocene sulfide. It readily loses sulfur upon reaction with PR3 (R = C6H5, OCH3) and CH3I to form compounds 4 and 5, which both contain the Ta = S moiety. Attempts to prepare `'classical'' metallocene sulfides by metathesis reaction of Cp'2NbCl2 and Li2S5 gave the polynuclear compounds Cp'3Nb3S10O (6) and Cp'4Nb4S13 (7).
The Hercules satellite: a stellar stream in the Milky Way halo?
Creators: name: Martin, Nicolas F.
name: Jin, Shoko
Publisher: name: arXiv
Year: 2010
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We investigate the possibility that the recently discovered Hercules Milky Way satellite is in fact a stellar stream in formation, thereby explaining its very elongated shape with an axis ratio of 3 to 1. Under the assumption that Hercules is a stellar stream and that its stars are flowing along the orbit of its progenitor, we find an orbit that would have recently brought the system close enough to the Milky Way to induce its disruption and transformation from a bound dwarf galaxy into a stellar stream. The application of simple analytical techniques to the tentative radial velocity gradient observed in the satellite provides tight constraints on the tangential velocity of the system (v_t = -16^{+6}_{-22} km/s in the Galactic Standard of Rest). Combined with its large receding velocity, the determined tangential velocity yields an orbit with a small pericentric distance (R_peri = 6^{+9}_{-2} kpc). Tidal disruption is therefore a valid scenario for explaining the extreme shape of Hercules. The increase in the mean flattening of dwarf galaxies as one considers fainter systems could therefore be the impact of a few of these satellites not being bound stellar systems dominated by dark matter but, in fact, stellar streams in formation, shedding their stars in the Milky Way's stellar halo.
description: 8 pages, 4 figures, accepted for publication in ApJ
Von Cp+2Nb(η2-S2)H zu CP+3Nb3S12: Reaktivitätsstudien an Niobocensulfiden ( = FROM CP+2NB(ETA-2-S2)H TO CP+3NB3S12 - REACTIVITY STUDIES ON NIOBOCENE SULFIDES)
Creators: name: Brunner, H.
name: Gehart, G.
name: Meier, W.
name: Wachter, Joachim
name: Nuber, B.
Publisher: name: Universität Regensburg
Year: 1993
Subjects: subject: 540 Chemie

description: The reaction of Cp+2bBH4 with sulfur gives two isomers of composition Cp+2NbS2H (3, 4) and Cp+2NbS3H (5). The structures of 3-5 have been investigated by IR and H-1 NMR spectroscopic means. X-Ray diffraction analyses have been performed on 3 and 4. These investigations demonstrate that 3 and 4 are niobocene derivatives, in which either a eta2-S-2(2)--ligand and a hydride (3) or a S2- and a SH- ligand (4) are attached to the Nb center. Complex 3 can be transformed thermally into 4 by a S-S bond rupture, followed by the insertion of sulfur into the Nb-H bond. The polynuclear compounds Cp+3Nb3S7 (6) and Cp+3Nb3S12 (7) can be formed by the reaction of 3 with S8. The role of polysulfide intermediates is discussed.
Inertial forces and dissipation on accelerated boundaries
Creators: name: Fosco, C. D.
name: Lombardo, F. C.
name: Mazzitelli, F. D.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study dissipative effects due to inertial forces acting on matter fields confined to accelerated boundaries in $1+1$, $2+1$, and $3+1$ dimensions. These matter fields describe the internal degrees of freedom of `mirrors' and impose, on the surfaces where they are defined, boundary conditions on a fluctuating `vacuum' field. We construct different models, involving either scalar or Dirac matter fields coupled to a vacuum scalar field, and use effective action techniques to calculate the strength of dissipation. In the case of massless Dirac fields, the results could be used to describe the inertial forces on an accelerated graphene sheet.
description: 7 pages, no figures
Cause or Trigger? From Philosophy to Causal Modeling
Creators: name: Wöß, Rainer
Publisher: name: Zenodo
Year: 2025
Subjects: Cause
Triggering Variable
Moderation
Physical Process
Cyclone

description: The files contain the experiment code and data for the identically titled paper. It aims to describe trigger and cause in the metaphysical sense and differentiating them algorithmically. This algorithm is validated on ERA5 data correspdonding to two cyclones' locations and expert's knowledge on their triggering variables.
Tomographic reconstruction of the three-dimensional structure of the HH30 jet
Creators: name: De Colle, Fabio
name: del Burgo, Carlos
name: Raga, Alejandro
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The physical parameters of Herbig-Haro jets are usually determined from emission line ratios, obtained from spectroscopy or narrow band imaging, assuming that the emitting region is homogeneous along the line of sight. Under the more general hypothesis of axisymmetry, we apply tomographic reconstruction techniques to the analysis of Herbig-Haro jets. We use data of the HH30 jet taken by Hartigan & Morse (2007) with the Hubble space telescope using the slitless spectroscopy technique. Using a non-parametric Tikhonov regularization technique, we determine the volumetric emission line intensities of the [SII]6716,6731, [OI]6300 and [NII]6583 forbidden emission lines. From our tomographic analysis of the corresponding line ratios, we produce "three-dimensional" images of the physical parameters. The reconstructed density, temperature and ionization fraction present much steeper profiles than those inferred using the assumption of homogeneity. Our technique reveals that the reconstructed jet is much more collimated than the observed one close to the source (a width ~ 5 AU vs. ~ 20 AU at a distance of 10 AU from the star), while they have similar widths at larger distances. In addition, our results show a much more fragmented and irregular jet structure than the classical analysis, suggesting that the the ejection history of the jet from the star-disk system has a shorter timescale component (~ some months) superimposed on a longer, previously observed timescale (of a few years). Finally, we discuss the possible application of the same technique to other stellar jets and planetary nebulae.
description: 13 pages, 9 figures, accepted by ApJ
New Discoveries in the Realm of Metal–Metal Multiple Bonds:[η5-(C5Me5)Co2], the First Organometallic Multiple-Bond Complex without Bridging Ligands
Creators: name: Wachter, Joachim
Publisher: name: Universität Regensburg
Year: 1991
Subjects: subject: 540 Chemie

description: Double bond, yes or no? That is the poignant question in the case of the complex [Cp*CoCoCp*] prepared by J.J. Schneider et al. The Co-Co distance and the number of electrons suggest a double bond, while the H-1-NMR spectrum and the poor reactivity toward C2H4 and CO would suggest the contrary. Nevertheless, with this unbridged complex, the prerequisite for the synthesis of further such compounds and for studying the properties of these multibond systems was realized.
Cerebrovascular and peripheral vascular regulation : role of oxidative stress
Creators: name: Hansen, Alexander Bradley
Publisher: name: University of British Columbia
Year: 2017

description: Oxidative stress is ultimately determined by the balance between pro- (e.g. free radicals) and antioxidants (e.g. vitamin C). The purpose of this thesis was to examine the role and effect of a combined mixture of oral antioxidants (vitamin C, E, and alpha-lipoic acid) on peripheral and cerebrovascular regulation at both sea-level (344m; n = 11 participants) and at high altitude (5050m; n=10) where oxidative stress is markedly elevated. In a randomized and double-blinded design, flow-mediated dilation, cardiorespiratory, cerebral blood flow, and CO₂ and hypoxic cerebrovascular reactivity tests were conducted before and 90 mins following antioxidants (vitamin C, E, and alpha-lipoic acid) or a placebo control, previous work has shown antioxidant levels increased in blood plasma after 90 mins of ingestion. Following 10-12 days at 5050m, in a similar design, flow-mediated dilation, cardiorespiratory, and resting cerebral blood flow tests were obtained. The primary findings were: 1) antioxidants did not alter flow-mediated dilation, resting cerebral blood flow, cerebrovascular reactivity to CO₂ or hypoxia at sea-level; 2) similarly, at high-altitude (Nepal, 5050m), antioxidants did not alter flow-mediated dilation or resting cerebral blood flow. In conclusion, this study highlights that at both sea-level and high-altitude, acute oral administration of antioxidants does not alter FMD or cerebrovascular reactivity to CO₂ or hypoxia. Nevertheless, continued exploration of this methodology is recommended, especially in the form of more chronic dosing of antioxidants in various pathologies (e.g., chronic pulmonary obstructed disease, diabetes, coronary artery disease) who present with excessive oxidative stress and reductions in both antioxidant capacity and vascular function. This study received ethical approval from the University of British Columbia Clinical Research Ethics Board (ID: H16-00101). This research was supported by a NSERC Discovery grant and Canadian Research Chair in Cerebrovascular Physiology.
Competition between Ferrimagnetism and Magnetic Frustration in Zinc Substituted YBaFe4O7
Creators: name: Sarkar, Tapati
name: Pralong, V.
name: Caignaert, V.
name: Raveau, B.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The substitution of zinc for iron in YBaFe4O7 has allowed the oxide series YBaFe4-xZnxO7, with 0.40 < x < 1.50, belonging to the "114" structural family to be synthesized. These oxides crystallize in the hexagonal symmetry (P63mc), as opposed to the cubic symmetry (F-43m) of YBaFe4O7. Importantly, the d.c. magnetization shows that the zinc substitution induces ferrimagnetism, in contrast to the spin glass behaviour of YBaFe4O7. Moreover, a.c. susceptibility measurements demonstrate that concomitantly these oxides exhibit a spin glass or a cluster glass behaviour, which increases at the expense of ferrimagnetism, as the zinc content is increased. This competition between ferrimagnetism and magnetic frustration is interpreted in terms of lifting of the geometric frustration, inducing the magnetic ordering, and of cationic disordering, which favours the glassy state.
description: 24 pages, 10 figures
Designations as National Reference Laboratories for pesticide residues
Creators: name: Barbini, Danilo Attard
Publisher: name: Zenodo
Year: 2019

description: Designation as National Reference Laboratory for pesticide residues in fruit and vegetables (NRL-FV), National Reference Laboratory for pesticide residues in products of animal origin (NRL-AO) and National Reference Laboratory for pesticide residues with single residue methods (NRL-SRM)
BASR Poll: Columbus Community Clinic Survey
Creators: name: Bureau Of Applied Social Research, Columbia University
Publisher: name: Roper Center for Public Opinion Research
Year: 2022

description: Doctor visits (1); clinic visits (2); doctor vs. clinic preference (1); knowledge of various diseases (16); feeling sick (1); patient referrals (13); physical symptoms (11); suspected illness (24); venereal disease diagnosis (8); treatment methods (37); checkup (4); feelings about treatment (37); reason for checkup (1); disease publicity (13); discussing diseases (5); state fair (5); knowledge about diseases (6); previous venereal diseases (4); methods of disease transmission (1); syphilis symptoms (7); premarital sex (4); worries about syphilis (2); hospital visitors (2); reading habits (6); radio listening (1); social habits (1); drinking habits (1); peers with syphilis (2); reasons for abstinence (1); vaccinations against venereal diseases (2); movies (1); disease prevention (1).
The Abundance Scatter in M33 from HII Regions: Is There Any Evidence for Azimuthal Metallicity Variations?
Creators: name: Bresolin, Fabio
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Optical spectra of 25 H II regions in the inner two kpc of the M33 disk have been obtained with the GMOS spectrograph at the Gemini North telescope. The oxygen abundance gradient measured from the detection of the [O III]4363 auroral line displays a scatter of approximately 0.06 dex, a much smaller value than recently reported by Rosolowsky & Simon in this galaxy. The analysis of the abundances for a large sample of H II regions derived from the R23 strong-line indicator confirms that the scatter is small over the full disk of M33, consistent with the measuring uncertainties, and comparable to what is observed in other spiral galaxies. No evidence is therefore found for significant azimuthal variations in the present-day metallicity of the interstellar medium in this galaxy on spatial scales from ~100 pc to a few kpc. A considerable fraction of M33 H II regions with auroral line detections show spectral features revealing sources of hard ionizing radiation (such as He II emission and large [Ne III], [O III] line fluxes). Since R23 is shown to severely underestimate the oxygen abundances in such cases, care must be taken in chemical abundance studies of extragalactic H II regions based on this strong-line indicator.
description: 9 pages, accepted for publication in the Astrophysical Journal
An investigation of multi-modal gaze-supported zoom and pan interactions in ultrasound machines
Creators: name: Halwani, Yasmin
Publisher: name: University of British Columbia
Year: 2017

description: We are investigating the potential and the challenges of integrating eye gaze tracking support into the interface of ultrasound machines used for routine diagnostic scans by sonographers. In this thesis, we follow a user-centred approach by first conducting a field study to understand the context of the end user. As a starting point to a gaze-supported interface, we focus on the zoom functions of ultrasound machines. We study gaze-supported approaches for the often-used zoom function in ultrasound machines and present two alternatives, One-step Zoom (OZ) and Multi-step Zoom (MZ). A state-based analysis on the zoom functions in ultrasound machines is presented followed by a state-based representation of the gaze-supported alternatives. The gaze-supported state representation extends the manual-based interaction by implicitly integrating gaze input to OZ and offering a gaze-supported alternative to moving the zoom box in MZ. Evaluations of the proposed interactions through a series of user studies, seventeen non-sonographers and ten sonographers, suggest an increased cognitive demand and time on task compared to the conventional manual-based interaction. However, participants also reported an increased focus on main tasks using the gaze-supported alternative, which could offer benefit to novice users. They also report a lowered physical interaction as the gaze input replaces some functions of the manual input.
title: Baumgarten, Oswald
title: Catalogus Professorum Halensis
titleType: Subtitle
title: Biografienportal Sachsen-Anhalt
titleType: Other
Creators: name: Catalogus Professorum Halensis
name: Eberle, Henrik
Publisher: name: Historisches Datenzentrum Sachsen-Anhalt,Institut für Landesgeschichte (Sachsen-Anhalt)
Year: 2025
Subjects: subject: History
classificationCode: 4023025-9
subject: Halle (Saale)
valueUri: https://d-nb.info/gnd/4023025-9
classificationCode: 4006804-3
subject: Biografie
valueUri: https://d-nb.info/gnd/4006804-3
classificationCode: 4166546-6
subject: Landesgeschichte
valueUri: https://d-nb.info/gnd/4166546-6
classificationCode: 4051181-9
subject: Sachsen-Anhalt
valueUri: https://d-nb.info/gnd/4051181-9
classificationCode: 1048495779
subject: Universität Halle (Saale) | Halle (Saale)
valueUri: https://d-nb.info/gnd/1048495779
classificationCode: 2024276-1
subject: Martin-Luther-Universität Halle-Wittenberg | Halle (Saale); Wittenberg
valueUri: https://d-nb.info/gnd/2024276-1
classificationCode: 4020517-4
subject: Geschichte
valueUri: https://d-nb.info/gnd/4020517-4
classificationCode: 7504326-9
subject: Universitätsgeschichte
valueUri: https://d-nb.info/gnd/7504326-9
classificationCode: 7504427-4
subject: Wissenschaftsgeschichte
valueUri: https://d-nb.info/gnd/7504427-4
subject: Biografienportal Sachsen-Anhalt
subject: Catalogus Professorum Halensis
classificationCode: 120134756
subject: Eberle, Henrik | 1970– | Historiker
valueUri: https://d-nb.info/gnd/120134756
classificationCode: 1349034509
subject: Baumgarten, Oswald | 1872– | Arzt
valueUri: https://d-nb.info/gnd/1349034509

description: Das Biografienportal Sachsen-Anhalt versammelt in Erst- und Zweitveröffentlichung oder zu Zwecken der Langzeitarchivierung Biografien von Menschen aus und in Sachsen-Anhalt. Integriert wurde der Catalogus Professorum Halensis, der durch Mitarbeitende des Instituts für Geschichte der Martin-Luther-Universität Halle-Wittenberg entstand. Dabei handelt es sich um ein bio-bibliografisches Online-Lexikon zu den Professoren der Universität Halle zwischen 1694 und 1968. Die Texte wurden vor allem von Henrik Eberle und anderen Mitarbeitenden zwischen 2005 und 2010 recherchiert und erstellt. Etliche Artikel zum Zeitraum 1694 bis 1817 verfasste Julia Schopferer. Bei der Überführung in das Biografienportal wurden die Lebensangaben neu recherchiert und Metadaten über Verfahren des Named Entity Recogniton erschlossen. Automatisiert erkannt wurden Personennamen, Ortsbezeichnungen und Körperschaften, die in der hier vorhandenen RTF-Datei indexiert vorliegt. Zudem wurden diese mit GND-Einträgen abgeglichen. Weiterhin erfolgte ein Abgleich mit der „Ontologie der historischen, deutschsprachigen Amts- und Berufsbezeichnungen“. Die Texte liegen im Jahr 2024 in zweifacher Ausgabe im Catalogus Professorum Halensis des Universitätsarchivs und des Biografienportals des Historischen Datenzentrums Sachsen-Anhalts vor. Sie werden hier für die Langzeitarchivierung der ursprünglichen Fassung archiviert.
description: https://www.catalogus-professorum-halensis.de/
description: Biografienportal Sachsen-Anhalt: https://www.histdata.uni-halle.de/
Reactivity studies on tantalocene(sulfido)hydride Cp′2Ta(S)H (Cp′= ButC5H4): cycloaddition on and protonation of the Ta=S ligand
Creators: name: Brunner, H.
name: Kubicki, Marek M.
name: Leblanc, J. C.
name: Moise, C.
name: Volpato, F.
name: Wachter, Joachim
Publisher: name: Universität Regensburg
Year: 1993
Subjects: subject: 540 Chemie

description: Reactions of the tantalocene(sulfido)hydride Cp'2Ta(=S)H with PhNCS and HCl exhibit a surprisingly low metal-hydride reactivity; the Ta=S bond being involved either in a [2 + 2] cycloaddition or a protonation.
Spontaneous Lorentz symmetry breaking in nonlinear electrodynamics
Creators: name: Urrutia, L. F.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We review some of the basic features and predictions of a gauge invariant spontaneous Lorentz symmetry breaking model arising from the nonzero vacuum expectation value of the electromagnetic tensor and leading to a nonlinear electrodynamics. The model is stable in the small Lorentz invariance violation approximation. The speed of light is independent of the frequency and one of the propagating modes is highly anisotropic. The bound (Delta c)/c < 10^{-32} is obtained for such anisotropy measured in perpendicular directions.
description: 5 pages, no figures, Invited talk to the Fifth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, June 28-July 2, 2010
Characterizing dynamical heterogeneity in a supercooled glass-forming diatomic liquid
Creators: name: Collins, Collin
name: Matsumura, George
name: Castillo, Horacio
Publisher: name: Zenodo
Year: 2025

description: We use molecular dynamics simulations to investigate a 3D supercooled liquid of diatomic molecules interacting via the Lennard-Jones potential. We simulate the system for temperatures approaching the glass transition and verify that the system does not crystallize by measuring local order parameters and correlation functions. We use the overlap to study the translational dynamics and introduce a rotational overlap measure to examine the orientational dynamics as the system slows down. We investigate the heterogeneous dynamics for both types of degrees of freedom.
utc2nwislocal, UTC date-times to NWIS local time zones using UTC offsets
Creators: name: Asquith, William H
name: Seanor, Ronald C
Publisher: name: U.S. Geological Survey
Year: 2020
Subjects: UTC, Coordinated Universal Time, National Water Information System, NWIS, time zone

description: The utc2nwislocal package in the R language provides a light-weight, dependency-free utility for converting Coordinated Universal Time (UTC) base::as.POSIXct() date-time values into character-string representations for time zones. The UTC offsets for individual time zones are determined from the time-zone codes recognized by the U.S. Geological Survey National Water Information System (NWIS) database. The time zones are tracked in a separate database slot than the UTC date time. Sometimes it can be difficult in the R language to work with its Olson time-zone naming convention (base:OlsonNames()) relative to the time zone codes of NWIS. This package could help users working with some NWIS-derived data sets.
Superlensing effect of an anisotropic metamaterial slab with near-zero dynamic mass
Creators: name: Zhou, Xiaoming
name: Hu, Gengkai
Publisher: name: arXiv
Year: 2011
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A metamaterial slab of anisotropic mass with one diagonal component being infinity and the other being zero is demonstrated to behave as a superlens for acoustic imaging beyond the diffraction limit. The underlying mechanism for extraordinary transmission of evanescent waves is attributed to the zero mass effect. Microstructure design for such anisotropic lens is also presented. In contrast to the anisotropic superlens based on Fabry-Pérot resonant mechanism, the proposed lens operates without the limitation on lens thickness, thus more flexible in practical applications. Numerical modeling is performed to validate the proposed ideas.
description: 4 figures
Mezirinae
Creators: name: Swanson, Daniel R.
name: Taylor, Steven J.
name: Heads, Sam W.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Aradidae

description: Key to the Mezirinae of Illinois   1 Fourth, fifth, and sixth abdominal sternites with narrow, sharp, transverse ventral ridge behind anterior margin; third antennomere at most only slightly longer than second (Neuroctenus).................................................. 2
- Ventral ridge absent behind anterior margin of fourth, fifth, and sixth abdominal sternites; third antennomere conspicuously longer than second................................................................................... 3
 2 (1) Seventh connexival segment of male with short, transverse fold; male paratergites reaching four-fifths length of large pygophore; third to seventh connexival segments of female with fold along outer border; female paratergites large, rounded, and reaching tip of tricuspidate ninth segment; abdomen broadly ovate.......................... Neuroctenus pseudonymus
 - Connexiva without folds in both sexes; male paratergites smaller, reaching only three-fourths length of posteriorly rounded pygophore; female paraterites subtriangular, not reaching tip of notched ninth segment; abdomen more-or-less parallel-sided..................................................................................... Neuroctenus simplex
 3 (1') Base of pronotum in front of scutellum trisinuate; ventral spiracles nearer to lateral margins than to anterior or posterior margins of segments; size small, length 4 mm or less (Nannium)....................................... Nannium pusio
 - Base of pronotum in front of scutellum more-or-less straight; ventral spiracles equidistant from lateral, anterior, and posterior margins of segments; size larger, usually 5 mm or more (Mezira)............................................... 4
 4 (3') Larger species, length 7 mm or more; scutellum with median carina distinct; head and pronotum sparsely granulated................................................................................................ Mezira lobata
- Smaller species, length not greater than 6.5 mm; scutellum with median carina obsolete or faint; head and pronotum densely granulated...........................................................................................5
 5 (4') Body with long, thick, erect setae; parameres with caudal margin more-or-less straight between apical lobe and median lobe of hypophysis............................................................................. Mezira granulata
 - Body with short, thin, appressed setae, each seta curving around associated tubercle; parameres with caudal margin more-orless sinuate between apical lobe and median lobe of hypophysis........................................ Mezira sayi
description: Published as part of Swanson, Daniel R., Taylor, Steven J. & Heads, Sam W., 2017, Nine true bugs (Heteroptera) newly-discovered in Illinois, pp. 571-585 in Zootaxa 4269 (4) on page 573, DOI: 10.11646/zootaxa.4269.4.10, http://zenodo.org/record/582799
title: Hole widening drilling penetration mechanism and performance evaluation in hard rock utilizing cutting analysis
Creators: name: Ahmed, A S Daiyan
Publisher: name: Memorial University of Newfoundland
Year: 2020

description: Mining by drilling technique, a revolutionary breakthrough which has already created a wind of change in the industry of ore excavation. Mineral production form the narrow veins is a matter of great challenge and mining by drilling technique is providing the unique solution for this type of excavation. Large diameter hole drilling is performed for accomplishment of excavation from narrow vein ore bodies. Conventional rotary drill rigs are used to drill a small pilot hole through the center of the vein and then the large diameter hole is drilled on the same hole where pilot bit works as a guide or stabilizer for large diameter bit. Pilot hole are drilled to understand the geology, geometry of the formation and the large diameter hole drilling works as the main production process of the ore. Lab based Drill-Off Tests were conducted to evaluate the pilot hole drilling and hole widening drilling process. Drill cuttings were used as the main source of information and shape, size, volume of the particles were examined carefully for proper assessment of the drilling process. Performance of these two types of drilling process were estimated based on Rate of Penetration (ROP), Revolution Per Minute (RPM), Mechanical Specific Energy (MSE) and Drilling Efficiency (DE). Relationship between drill cuttings particle size parameters and drilling parameters were investigated for proper appraisal of hole widening drilling process. A detailed study was performed to assist field scale hole widening drilling operations that involves intensive analysis of cuttings, drilling parameters, and drilling performance.
Renormalized kinetic theory of classical fluids in and out of equilibrium
Creators: name: Daligault, Jerome
Publisher: name: arXiv
Year: 2011
Subjects: subject: Classical Physics (physics.class-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We present a theory for the construction of renormalized kinetic equations to describe the dynamics of classical systems of particles in or out of equilibrium. A closed, self-consistent set of evolution equations is derived for the single-particle phase-space distribution function $f$, the correlation function $C=$, the retarded and advanced density response functions $χ^{R,A}=δf/δϕ$ to an external potential $ϕ$, and the associated memory functions $Σ^{R,A,C}$. The basis of the theory is an effective action functional $Ω$ of external potentials $ϕ$ that contains all information about the dynamical properties of the system. In particular, its functional derivatives generate successively the single-particle phase-space density $f$ and all the correlation and density response functions, which are coupled through an infinite hierarchy of evolution equations. Traditional renormalization techniques are then used to perform the closure of the hierarchy through memory functions. The latter satisfy functional equations that can be used to devise systematic approximations. The present formulation can be equally regarded as (i) a generalization to dynamical problems of the density functional theory of fluids in equilibrium and (ii) as the classical mechanical counterpart of the theory of non-equilibrium Green's functions in quantum field theory. It unifies and encompasses previous results for classical Hamiltonian systems with any initial conditions. For equilibrium states, the theory reduces to the equilibrium memory function approach. For non-equilibrium fluids, popular closures (e.g. Landau, Boltzmann, Lenard-Balescu) are simply recovered and we discuss the correspondence with the seminal approaches of Martin-Siggia-Rose and of Rose.and we discuss the correspondence with the seminal approaches of Martin-Siggia-Rose and of Rose.
description: 63 pages, 10 figures
Untersuchungen zum Einfluß des Biscyclopentadienylmethanliganden auf die Bildung von Cyclopentadienylchromsulfiden ( = EFFECT OF BISCYCLOPENTADIENYLMETHANE LIGANDS ON CYCLOPENTADIENYLCHROMIUM SULFIDE FORMATION)
Creators: name: Brunner, Henri
name: Grassl, R.
name: Wachter, Joachim
Publisher: name: Universität Regensburg
Year: 1992
Subjects: subject: 540 Chemie

description: The reaction of bcpmCr2(CO)6 (bcpm = biscyclopentadienylmethane) with sulfur gives in a stepwise reaction the complexes bcpmCr2(CO)4S (2) and bcpm2Cr4S4 (3). The products were investigated by IR and low temperature H-1 NMR spectroscopy. The H-1 NMR spectra of 2 show upon cooling a dynamic process similar to that in the starting material. It is ascribed to a topomerization process in the bridging ligand. The cluster 3 which belongs to the heterocubane type exhibits a magnetic behavior which is inbetween that of the antiferromagnetic clusters of type CP4Cr4O4 (CP = any substituted eta-5-C5H5 ring) and the diamagnetic CP4Cr4S4 cubanes.
Einfluß verschiedenartig substituierter Cyclopentadienylliganden auf die Chemie schwefelreicher Organometallkomplexe mit Metallen der 6. Nebengruppe ( = INFLUENCE OF DIFFERENTLY SUBSTITUTED CYCLOPENTADIENYL LIGANDS ON CHEMISTRY OF ORGANOMETAL COMPLEXES WITH SULFUR)
Creators: name: Brunner, Henri
name: Grassl, Roland
name: Meier, Walter
name: Wachter, Joachim
name: Nuber, Bernd
name: Ziegler, M. L.
Publisher: name: Universität Regensburg
Year: 1992
Subjects: subject: 540 Chemie

description: The reaction of the differently substituted cyclopentadienyl complexes L2M2(CO)4 with sulfur is investigated with respect to the ligand L (etmcp = ethyltetramethylcyclopentadienyl, tbcp = t-butylcyclopentadienyl, ipcp = isopropylcyclopentadienyl) and the metal M (Cr, Mo, W). For M = Cr the only isolated product is etmcp2Cr2S5. For M = Mo three isomers A, D, E of composition L2Mo2S4 (L = ipcp, etmcp) are formed whereas only two isomers (A, D) exist for L = tbcp. Only two isomers (D, E) of composition L2W2S4 are formed in the system L2W2(CO)4/S8, a further product is L2W2(CO)2S3 for L = etmcp. Structural characterisation of all compounds was achieved by IR, H-1, and Mo-95 NMR spectroscopy, whereas the structures of syn-etmcp2M2(mu-S)2S2 (M = Mo, W) were determined by X-ray crystallography, the result of which allows the correction of a previous structure assignment. It is further shown that a thermal equilibrium exists between L2Mo2(mu,eta-2-S2)(mu-S)2 (A) and syn-L2Mo2(mu-S)2S2 (D) which depends strongly on the ligands.
Berytidae
Creators: name: Swanson, Daniel R.
name: Taylor, Steven J.
name: Heads, Sam W.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Berytidae

description: Key to the Berytidae of Illinois   1 Head long, tylus anteriorly produced into prominent down-curved cylindrical process; scutellum without basal spine or tubercle; ostiolar process short, apically flared and rounded, neither long nor produced into spine-like metasternal process; eyes very distant from base of head; venter strongly punctate; ocelli with teardrop-shaped base; body with appressed sericeous or wooly pubescence, especially on head, pronotum, and along rostral groove (Berytinae: Neoneides)...... Neoneides muticus
- Head short, tylus not anteriorly produced, although sometimes bearing fine spine or short conical tubercle; ostiolar process produced into tubercle or generally into long canaliculate, twisted, spine-like metasternal process; eyes near to base of head;
 venter not punctate; ocelli with round base; body generally without pubescence, at least never on pronotum (Metacanthinae).................................................................................................... 2 2 (1') Fourth antennomere shorter than length of head; apex of ostiolar process apically rounded or slightly angulate, lacking a spine; channel of scent gland strongly twisted to run along outer surface basally, then curving sharply to terminate along dorsal surface; size smaller, 4.5–6.5 mm (Metacanthus); abdomen frequently with greenish tinge........... Metacanthus multispinus
 - Fourth antennomere longer than length of head; apex of ostiolar process ending in sharp to blunt spine; channel of scent gland lying on same side of process for its entire length; size larger, 6.0–10.0 mm (Jalysus); abdomen usually testaceous or brownish................................................................................................... 3
 3 (2’) Sides of head before and behind eyes with only few scattered punctures, mostly near ventral margin; pygophore with apical transverse depression; parameres somewhat slender, with one small outer process...................... Jalysus spinosus
 - Sides of head before and behind eyes strongly punctate; pygophore with median carina, ridges appearing apically T-shaped; parameres thickened, with small outer process and two conspicuous processes at middle of mesal margin... Jalysus wickhami
description: Published as part of Swanson, Daniel R., Taylor, Steven J. & Heads, Sam W., 2017, Nine true bugs (Heteroptera) newly-discovered in Illinois, pp. 571-585 in Zootaxa 4269 (4) on pages 575-576, DOI: 10.11646/zootaxa.4269.4.10, http://zenodo.org/record/582799
Efficient Triangle Counting in Large Graphs via Degree-based Vertex Partitioning
Creators: name: Kolountzakis, Mihail N.
name: Miller, Gary L.
name: Peng, Richard
name: Tsourakakis, Charalampos E.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Data Structures and Algorithms (cs.DS)
subject: Social and Information Networks (cs.SI)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: The number of triangles is a computationally expensive graph statistic which is frequently used in complex network analysis (e.g., transitivity ratio), in various random graph models (e.g., exponential random graph model) and in important real world applications such as spam detection, uncovering of the hidden thematic structure of the Web and link recommendation. Counting triangles in graphs with millions and billions of edges requires algorithms which run fast, use small amount of space, provide accurate estimates of the number of triangles and preferably are parallelizable. In this paper we present an efficient triangle counting algorithm which can be adapted to the semistreaming model. The key idea of our algorithm is to combine the sampling algorithm of Tsourakakis et al. and the partitioning of the set of vertices into a high degree and a low degree subset respectively as in the Alon, Yuster and Zwick work treating each set appropriately. We obtain a running time $O \left(m + \frac{m^{3/2} Δ\log{n}}{t ε^2} \right)$ and an $ε$ approximation (multiplicative error), where $n$ is the number of vertices, $m$ the number of edges and $Δ$ the maximum number of triangles an edge is contained. Furthermore, we show how this algorithm can be adapted to the semistreaming model with space usage $O\left(m^{1/2}\log{n} + \frac{m^{3/2} Δ\log{n}}{t ε^2} \right)$ and a constant number of passes (three) over the graph stream. We apply our methods in various networks with several millions of edges and we obtain excellent results. Finally, we propose a random projection based method for triangle counting and provide a sufficient condition to obtain an estimate with low variance.
description: 1) 12 pages 2) To appear in the 7th Workshop on Algorithms and Models for the Web Graph (WAW 2010)
Synthesis, Structure and Reactivity of Sulfur-Rich Cyclopentadienyl-Transition Metal Complexes: Sulfur Chemistry from an Organometallic Point of View
Creators: name: Wachter, Joachim
Publisher: name: Universität Regensburg
Year: 1989
Subjects: subject: 540 Chemie

description: Metal-sulfur centers play an important role in the activity of metalloproteins in enzymatic catalysis and the activity of metal sulfides as heterogeneous catalysts. The systematic search for M[BOND]S model compounds led to the discovery of an interesting and novel structural chemistry, which stems from the numerous coordination possibilities of sulfur ligands. The intention of this review article is to present and outline new approaches to sulfur chemistry from the organometallic point of view. Reactive cyclopentadienyl-transition metal fragments incorporate elemental sulfur to give polynuclear sulfur-rich complexes, which can contain either mono-, di- or polysulfido ligands or several such ligands in combined form. The versatile structural chemistry of the complexes formed and their reactivity towards organic, inorganic and organometallic compounds are discussed, and examples of some simple and rational procedures for their synthesis starting from cyclopentadienylcarbonyl- and cyclopentadienylhydrido-complexes are outlined. Their reactivity is manifested in numerous metal- and ligandcentered reactions. Finally the, albeit far less extensive, complex chemistry of the other chalcogens (O, Se, Te) is also considered for comparison, thus providing a more detailed survey of particular aspects of this area of chemistry.
Spikes and diffusion waves in one-dimensional model of chemotaxis
Creators: name: Karch, Grzegorz
name: Suzuki, Kanako
Publisher: name: arXiv
Year: 2010
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35Q, 35K55, 35B40

description: We consider the one-dimensional initial value problem for the viscous transport equation with nonlocal velocity $u_t = u_{xx} - \left(u (K^\prime \ast u)\right)_{x}$ with a given kernel $K'\in L^1(\R)$. We show the existence of global-in-time nonnegative solutions and we study their large time asymptotics. Depending on $K'$, we obtain either linear diffusion waves ({\it i.e.}~the fundamental solution of the heat equation) or nonlinear diffusion waves (the fundamental solution of the viscous Burgers equation) in asymptotic expansions of solutions as $t\to\infty$. Moreover, for certain aggregation kernels, we show a concentration of solution on an initial time interval, which resemble a phenomenon of the spike creation, typical in chemotaxis models.
Phymatinae
Creators: name: Swanson, Daniel R.
name: Taylor, Steven J.
name: Heads, Sam W.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Reduviidae

description: Key to the Phymatinae of Illinois   1 Size small, length 5–6.5 mm; scutellum with linear or sublinear carina, lateral branches absent or obsolete................................................................................................. Phymata vicina vicina
- Size larger, length larger than 7 mm; scutellum with cruciform carina, lateral branches well-developed................ 2
 2 (1') Posterolateral angles of first three connexival segments noticeably protruding and dentiform; lateral margin of fourth connexival segment distinctly curved to sinuate.............................................. Phymata fasciata fasciata
- Posterolateral angles of first three connexival segments more or less straight, at most with small salient angles; lateral margin of fourth connexival segment more-or-less straight.......................................................... 3
 3 (2') Fourth connexivum not abruptly dilated, lateral margin near junction of third and fourth connexivum more or less straight, outline of connexival segments 1–3 not smooth, often with small salient angles posterolaterally; male with fourth antennal segment at most subequal in length to second and third combined; size slightly larger, length 8.5–10 mm............................................................................................... Phymata americana americana
 - Fourth connexivum abruptly dilated, lateral margin near junction of third and fourth connexivum distinctly angulate, especially in the males, outline of connexival segments 1–3 entire, smooth, usually without projecting angles posterolaterally; male with fourth antennal segment distinctly longer than second and third combined; size slightly smaller, length 7.5–9 mm............................................................................................ Phymata pennsylvanica
description: Published as part of Swanson, Daniel R., Taylor, Steven J. & Heads, Sam W., 2017, Nine true bugs (Heteroptera) newly-discovered in Illinois, pp. 571-585 in Zootaxa 4269 (4) on page 580, DOI: 10.11646/zootaxa.4269.4.10, http://zenodo.org/record/582799