cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Signifiers as a First-class Abstraction in Hypermedia Multi-Agent Systems
Creators: name: Vachtsevanou, Danai
name: Ciortea, Andrei
name: Mayer, Simon
name: Lemée, Jérémy
Publisher: name: arXiv
Year: 2023
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Multiagent Systems (cs.MA)
subject: FOS: Computer and information sciences

description: Hypermedia APIs enable the design of reusable hypermedia clients that discover and exploit affordances on the Web. However, the reusability of such clients remains limited since they cannot plan and reason about interaction. This paper provides a conceptual bridge between hypermedia-driven affordance exploitation on the Web and methods for representing and reasoning about actions that have been extensively explored for Multi-Agent Systems (MAS) and, more broadly, Artificial Intelligence. We build on concepts and methods from Affordance Theory and Human-Computer Interaction that support interaction efficiency in open and evolvable environments to introduce signifiers as a first-class abstraction in Web-based MAS: Signifiers are designed with respect to the agent-environment context of their usage and enable agents with heterogeneous abilities to act and to reason about action. We define a formal model for the contextual exposure of signifiers in hypermedia environments that aims to drive affordance exploitation. We demonstrate our approach with a prototypical Web-based MAS where two agents with different reasoning abilities proactively discover how to interact with their environment by perceiving only the signifiers that fit their abilities. We show that signifier exposure can be inherently managed based on the dynamic agent-environment context towards facilitating effective and efficient interactions on the Web.
About AGN ionization echoes, thermal echoes, and ionization deficits in low redshift Lyman-alpha blobs
Creators: name: Schirmer, Mischa
name: Malhotra, Sangeeta
name: Levenson, Nancy A.
name: Fu, Hai
name: Davies, Rebecca L.
name: Keel, William C.
name: Torrey, Paul
name: Bennert, Vardha N.
name: Pancoast, Anna
name: Turner, James E. H.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We report the discovery of 14 Lyman-alpha blobs (LABs) at z~0.3, existing at least 4-7 billion years later in the Universe than all other LABs known. Their optical diameters are 20-70 kpc, and GALEX data imply Ly-alpha luminosities of (0.4-6.3)x10^43 erg/s. Contrary to high-z LABs, they live in low-density areas. They are ionized by AGN, suggesting that cold accretion streams as a power source must deplete between z=2 and z=0.3. We also show that transient AGN naturally explain the ionization deficits observed in many LABs: Their Ly-alpha and X-ray fluxes decorrelate below 10^6 years because of the delayed escape of resonantly scattering Ly-alpha photons. High Ly-alpha luminosities do not require currently powerful AGN, independent of obscuration. Chandra X-ray data reveal intrinsically weak AGN, confirming the luminous optical nebulae as impressive ionization echoes. For the first time, we also report mid-infrared thermal echoes from the dusty tori. We conclude that the AGN have faded by 3-4 orders of magnitude within the last 10^(4-5) years, leaving fossil UV, optical and thermal radiation behind. The host galaxies belong to the group of previously discovered Green Bean galaxies (GBs). Gemini optical imaging reveals smooth spheres, mergers, spectacular outflows and ionization cones. Because of their proximity and high flux densities, GBs are perfect targets to study AGN feedback, mode switching and the Ly-alpha escape. The fully calibrated, coadded optical FITS images are publicly available.
description: 36 pages, 27 figures. Accepted for publication in MNRAS 2016 July 21. The coadded gri FITS images are publicly available at https://zenodo.org/record/56059
Constraints on the onset of color transparency from quasi-elastic $^{12}$C$(e,e'p)$ up to $Q^2=\,14.2\,$(GeV$/c)^2$
Creators: name: Bhetuwal, D.
name: Matter, J.
name: Szumila-Vance, H.
name: Gayoso, C. Ayerbe
name: Kabir, M. L.
name: Dutta, D.
name: Ent, R.
name: Abrams, D.
name: Ahmed, Z.
name: Aljawrneh, B.
name: Alsalmi, S.
name: Ambrose, R.
name: Androic, D.
name: Armstrong, W.
name: Asaturyan, A.
name: Assumin-Gyimah, K.
name: Bandari, A.
name: Basnet, S.
name: Berdnikov, V.
name: Bhatt, H.
name: Biswas, D.
name: Boeglin, W. U.
name: Bosted, P.
name: Brash, E.
name: Bukhari, M. H. S.
name: Chen, H.
name: Chen, J. P.
name: Chen, M.
name: Christy, E. M.
name: Covrig, S.
name: Craycraft, K.
name: Danagoulian, S.
name: Day, D.
name: Diefenthaler, M.
name: Dlamini, M.
name: Dunne, J.
name: Duran, B.
name: Evans, R.
name: Fenker, H.
name: Fomin, N.
name: Fuchey, E.
name: Gaskell, D.
name: Gautam, T. N.
name: Gonzalez, F. A.
name: Hansen, J. O.
name: Hauenstein, F.
name: Hernandez, A. V.
name: Horn, T.
name: Huber, G. M.
name: Jones, M. K.
name: Joosten, S.
name: Karki, A.
name: Keppel, C.
name: Khanal, A.
name: King, P. M.
name: Kinney, E.
name: Ko, H. S.
name: Kohl, M.
name: Lashley-Colthirst, N.
name: Li, S.
name: Li, W. B.
name: Liyanage, A. H.
name: Mack, D.
name: Malace, S.
name: Markowitz, P.
name: Meekins, D.
name: Michaels, R.
name: Mkrtchyan, A.
name: Mkrtchyan, H.
name: Nazeer, S. J.
name: Nanda, S.
name: Niculescu, G.
name: Niculescu, I.
name: Nguyen, D.
name: Nuruzzaman
name: Pandey, B.
name: Park, S.
name: Pooser, E.
name: Puckett, A.
name: Rehfuss, M.
name: Reinhold, J.
name: Santiesteban, N.
name: Sawatzky, B.
name: Smith, G. R.
name: Sun, A.
name: Tadevosyan, V.
name: Trotta, R.
name: Wood, S. A.
name: Yero, C.
name: Zhang, J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Quasi-elastic scattering on $^{12}$C$(e,e'p)$ was measured in Hall C at Jefferson Lab for space-like 4-momentum transfer squared $Q^2$ in the range of 8--14.2\,(GeV/$c$)$^2$ with proton momenta up to 8.3\,GeV/$c$. The experiment was carried out in the upgraded Hall C at Jefferson Lab. It used the existing high momentum spectrometer and the new super high momentum spectrometer to detect the scattered electrons and protons in coincidence. The nuclear transparency was extracted as the ratio of the measured yield to the yield calculated in the plane wave impulse approximation. Additionally, the transparency of the $1s_{1/2}$ and $1p_{3/2}$ shell protons in $^{12}$C was extracted, and the asymmetry of the missing momentum distribution was examined for hints of the quantum chromodynamics prediction of Color Transparency. All of these results were found to be consistent with traditional nuclear physics and inconsistent with the onset of Color Transparency.
An investigation of word object association behaviour in trainable mentally retarded children
Creators: name: Jackson, Merrill S.
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Gaussian Quantum Illumination via Monotone Metrics
Creators: name: Kim, Dong Hwan
name: Jo, Yonggi
name: Kim, Duk Y.
name: Jeong, Taek
name: Kim, Jihwan
name: Park, Nam Hun
name: Kim, Zaeill
name: Lee, Su-Yong
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quantum illumination is to discern the presence or absence of a low reflectivity target, where the error probability decays exponentially in the number of copies used. When the target reflectivity is small so that it is hard to distinguish target presence or absence, the exponential decay constant falls into a class of objects called monotone metrics. We evaluate monotone metrics restricted to Gaussian states in terms of first-order moments and covariance matrix. Under the assumption of a low reflectivity target, we explicitly derive analytic formulae for decay constant of an arbitrary Gaussian input state. Especially, in the limit of large background noise and low reflectivity, there is no need of symplectic diagonalization which usually complicates the computation of decay constants. First, we show that two-mode squeezed vacuum (TMSV) states are the optimal probe among pure Gaussian states with fixed signal mean photon number. Second, as an alternative to preparing TMSV states with high mean photon number, we show that preparing a TMSV state with low mean photon number and displacing the signal mode is a more experimentally feasible setup without degrading the performance that much. Third, we show that it is of utmost importance to prepare an efficient idler memory to beat coherent states and provide analytic bounds on the idler memory transmittivity in terms of signal power, background noise, and idler memory noise. Finally, we identify the region of physically possible correlations between the signal and idler modes that can beat coherent states.
description: 16 pages, 6 figures
Controlling the Multiport Nature of Bragg Diffraction in Atom Interferometry
Creators: name: Parker, Richard H
name: Yu, Chenghui
name: Estey, Brian
name: Zhong, Weicheng
name: Huang, Eric
name: Müller, Holger
Publisher: name: arXiv
Year: 2016
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Bragg diffraction has been used in atom interferometers because it allows signal enhancement through multiphoton momentum transfer and suppression of systematics by not changing the internal state of atoms. Its multi-port nature, however, can lead to parasitic interferometers, allows for intensity-dependent phase shifts in the primary interferometers, and distorts the ellipses used for phase extraction. We study and suppress these unwanted effects. Specifically, phase extraction by ellipse fitting and the resulting systematic phase shifts are calculated by Monte Carlo simulations. Phase shifts arising from the thermal motion of the atoms are controlled by spatial selection of atoms and an appropriate choice of Bragg intensity. In these simulations, we found that Gaussian Bragg pulse shapes yield the smallest systematic shifts. Parasitic interferometers are suppressed by a "magic" Bragg pulse duration. The sensitivity of the apparatus was improved by the addition of AC Stark shift compensation, which permits direct experimental study of sub-part-per-billion (ppb) systematics. This upgrade allows for a 310\,$\hbar k$ momentum transfer, giving an unprecedented 6.6\,Mrad measured in a Ramsey-Bordé interferometer.
Learning to Dexterously Pick or Separate Tangled-Prone Objects for Industrial Bin Picking
Creators: name: Zhang, Xinyi
name: Domae, Yukiyasu
name: Wan, Weiwei
name: Harada, Kensuke
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Industrial bin picking for tangled-prone objects requires the robot to either pick up untangled objects or perform separation manipulation when the bin contains no isolated objects. The robot must be able to flexibly perform appropriate actions based on the current observation. It is challenging due to high occlusion in the clutter, elusive entanglement phenomena, and the need for skilled manipulation planning. In this paper, we propose an autonomous, effective and general approach for picking up tangled-prone objects for industrial bin picking. First, we learn PickNet - a network that maps the visual observation to pixel-wise possibilities of picking isolated objects or separating tangled objects and infers the corresponding grasp. Then, we propose two effective separation strategies: Dropping the entangled objects into a buffer bin to reduce the degree of entanglement; Pulling to separate the entangled objects in the buffer bin planned by PullNet - a network that predicts position and direction for pulling from visual input. To efficiently collect data for training PickNet and PullNet, we embrace the self-supervised learning paradigm using an algorithmic supervisor in a physics simulator. Real-world experiments show that our policy can dexterously pick up tangled-prone objects with success rates of 90%. We further demonstrate the generalization of our policy by picking a set of unseen objects. Supplementary material, code, and videos can be found at https://xinyiz0931.github.io/tangle.
description: 8 pages, IEEE RA-L, 2023
Electroweak renormalization based on gauge-invariant vacuum expectation values of non-linear Higgs representations: 2. extended Higgs sectors
Creators: name: Dittmaier, Stefan
name: Rzehak, Heidi
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: A recently proposed scheme for a gauge-invariant treatment of tadpole corrections in spontaneously broken gauge theories - called Gauge-Invariant Vacuum expectation value Scheme (GIVS) - is applied to a singlet Higgs extension of the Standard Model and to the Two-Higgs Doublet Model. In contrast to previously used tadpole schemes, the GIVS unifies the gauge-invariance property with perturbative stability. For the Standard Model this was demonstrated for the conversion between on-shell and MSbar renormalized masses, where the GIVS leads to very moderate, gauge-independent electroweak corrections. In models with extended scalar sectors, issues with tadpole renormalization exist if Higgs mixing angles are renormalized with MSbar conditions, which is the major subject of this article. In detail, we first formulate non-linear representations of the extended scalar sectors, which is an interesting subject in its own right. Then we formulate the GIVS which employs these non-linear representations in the calculation of the tadpole renormalization constants, while actual higher-order calculations in the GIVS proceed in linear representations as usual. Finally, for the considered models we discuss the next-to-leading-order (electroweak and QCD) corrections to the decay processes $h/H\to WW/ZZ\to4\,$fermions of the CP-even neutral Higgs bosons h and H using MSbar-renormalized Higgs mixing angles with the GIVS and previously used tadpole treatments.
description: 40 pages, latex, typos in Eqs.(3.33) and (3.59) corrected, all results unchanged
An investigation into the hex1 gene and gene promoter for the enhancement of protein production in Trichoderma reesei
Creators: name: Curach, Natalie Claire
Publisher: name: Macquarie University
Year: 2022
Subjects: Other education not elsewhere classified

description: For Trichoderma reesei to be developed as an effiecient producer of a large variety of proteins, the expression system requires diversification. In particular, the choice of promoters available needs to be broadened to include promoters which are active in conditions other than those conducive to induction of cellulase expression. Using proteomics, the HEX1 protein was identified as an abundant protein of the cell envelope of T. reesei when grown on a range of carbon sources, suggesting that a strong constitutive promoter drives the expression of this physiologically important protein. This thesis is an exploration into the hex1 gene promoter and the role of hex1 in the maintenance of mycelium integrity in T. reesei with consideration for the application of this gene in the further development of filamentous fungi as protein expression systems. -- The single copy hex1 gene and flanking regions were isolated from T. reesei and another biotechnologically important fungus, Ophiostoma floccosum. The fluorescent reporter protein DsRed1-E5 was expressed under the T. reesei hex1 promoter and promoter activity was monitored by fluorescence CLSM and RNA analysis. During the rapid growth phase of a culture, the hex1 promoter was active in a range of carbon sources and three transcipt types with alternative tsp and splicing sites were discovered for the hex1 gene. The distribution of fluorescence throughout the mycelium suggested spatial regulation of the hex1 promoter as well as temporal regulation. The promoter was continually active in the absence of a functional hex1 gene product suggesting that the hex1 promoter is regulated in part, by negative feedback from the endogenous gene product. Interruption of the hex1 gene produced hyphae that leaked excessive volumes of cytoplasm when physically damaged which may be advantageous for the externalisation of selected protein products. The results indicate that the regulation of the hex1 hene promoter is complex and that the hex1 gene is integral to the maintenance of the integrity of the fungal mycelium.
Exact Propagator of a two dimensional anisotropic Harmonic Oscillator in the presence of a Magnetic Field
Creators: name: Cervero, Jose M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this paper we solve exactly the problem of the spectrum and Feynman propagator of a charged particle submitted to both an anharmonic oscillator in the plane and a constant and homogeneous magnetic field of arbitrary strength aligned with the perpendicular direction to the plane. As we shall see in the beginning of the letter the Hamiltonian, being a quadratic form, is easily diagonalizable and the Classical Action can be used to construct the exact Feynman Propagator using the Stationary Phase Approximation. The result is useful for the treatment of quasi two dimensional samples in the field of magnetic effects in nano-structures and quantum optics. The presented solution, after minor extensions, can also be used for motion in three dimensions, and in fact it has been used for years in such cases. Also it can be used as a good exercise of a Feynman Path Integral that can be calculated easily with just the help of the Classical Action.
description: 14 pages. No Figures
Emission of neutron-proton and proton-proton pairs in electron scattering induced by meson-exchange currents
Creators: name: Simo, I. Ruiz
name: Amaro, J. E.
name: Barbaro, M. B.
name: De Pace, A.
name: Caballero, J. A.
name: Megias, G. D.
name: Donnelly, T. W.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We use a relativistic model of meson-exchange currents to compute the proton-neutron and proton-proton yields in $(e,e')$ scattering from $^{12}$C in the 2p-2h channel. We compute the response functions and cross section with the relativistic Fermi gas model for a range of kinematics from intermediate to high momentum transfers. We find a large contribution of neutron-proton configurations in the initial state, as compared to proton-proton pairs. The different emission probabilities of distinct species of nucleon pairs are produced in our model only by meson-exchange currents, mainly by the $Δ$ isobar current. We also analyze the effect of the exchange contribution and show that the direct/exchange interference strongly affects the determination of the np/pp ratio.
description: 5 pages, 6 figures
Expansion complexity and linear complexity of sequences over finite fields
Creators: name: Mérai, László
name: Niederreiter, Harald
name: Winterhof, Arne
Publisher: name: arXiv
Year: 2016
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: The linear complexity is a measure for the unpredictability of a sequence over a finite field and thus for its suitability in cryptography. In 2012, Diem introduced a new figure of merit for cryptographic sequences called expansion complexity. We study the relationship between linear complexity and expansion complexity. In particular, we show that for purely periodic sequences both figures of merit provide essentially the same quality test for a sufficiently long part of the sequence. However, if we study shorter parts of the period or nonperiodic sequences, then we can show, roughly speaking, that the expansion complexity provides a stronger test. We demonstrate this by analyzing a sequence of binomial coefficients modulo $p$. Finally, we establish a probabilistic result on the behavior of the expansion complexity of random sequences over a finite field.
Path Integral Quantum Monte Carlo Calculations of Light Nuclei
Creators: name: Chen, Rong
name: Schmidt, Kevin E.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We describe a path-integral ground-state quantum Monte Carlo method for light nuclei in continuous space. We show how to efficiently update and sample the paths with spin-isospin dependent and spin-orbit interactions. We apply the method to the triton and alpha particle using both local chiral interactions with next-to-next-to-leading-order %(N$^2$LO) and the Argonne interactions. For operators, like the total energy, that commute with the Hamiltonian, our results agree with Green's function Monte Carlo and auxiliary field diffusion Monte Carlo calculations. For operators that do not commute with the Hamiltonian and for Euclidean response functions, the path-integral formulation allows straightforward calculation without forward walking or the increased variance typical of diffusion methods. We demonstrate this by calculating density distributions, root mean square radii, and Euclidean response functions for single-nucleon couplings.
description: 15 pages, 9 figures, 6 tables. Accepted by Physical Review C on 2022-9-28; published on 2022-10-26
Enzyme activities of fungi isolated from koala faeces
Creators: name: Peterson, Robyn Anne
Publisher: name: Macquarie University
Year: 2022
Subjects: Other education not elsewhere classified

description: Filamentous fungi secrete enzymes to break down complex substances in the environment into smaller molecules they can use for nutrition. Investigation of the enzymes secreted by a fungus can lead to a better understanding of how it survives in a natural habitat; furthermore, new enzymes with potential for industrial applications can be revealed. In this work, the enzyme activities of fungi from koala faeces were investigated. As a result of a diet of Eucalyptus leaves, koala faeces are composed of recalcitrant plant cell wall polymers (cellulose, hemicellulose, pectin and lignin). Consequently, fungi that grow on koala faeces hold high potential as sources of enzymes for efficient degradation of plant biomass. -- Thirty-seven fungal strains were isolated from koala faeces, identified, and screened for enzyme activities using agar plate assays; over two-thirds of the isolates secreted xylanases, endoglucanases, ligninases and proteases, and over one-third secreted amylases, mannanases and tannases. The enzyme activities of seven isolates were comprehensively characterised using liquid cultures, liquid enzyme assays and zymography. Two isolates, Gelasinospora cratophora A10 and Trichoderma atroviride A2, were high secretors of protein and heat-tolerant enzymes. The lipase(s) from Mariannaea camptospora A11 sustained activity at cool temperatures. The xylanase(s), mannanase(s), endoglucanase(s) and β-glucosidase(s) of Doratomyces stemonitis C8 displayed optimal activities under neutral to alkaline conditions. Some of the enzymes hold potential for application in the production of paper, textiles, detergents and ethanol-based biofuels. -- Finally, the secretome of D. stemonitis C8 was studied by gel electrophoresis and mass spectrometry. As the genome of D. stemonitis has not been sequenced, the secretome analysis required cross-species identification and de novo sequencing; furthermore, a new technique was developed to identify proteins directly from zymogram gels by mass spectrometry. In the first secretome analysis of a coprophilous fungus, a complex array of enzymes integral to plant biomass degradation was identified, including enzymes that could be of value to industry in the future.
Designing visual analysis training for the individual learner : an examination of individual learner differences and training content and procedures
Creators: name: McNamara, Suzanne E.
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Adaptive Neural Network-based Unscented Kalman Filter for Robust Pose Tracking of Noncooperative Spacecraft
Creators: name: Park, Tae Ha
name: D'Amico, Simone
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This paper presents a neural network-based Unscented Kalman Filter (UKF) to estimate and track the pose (i.e., position and orientation) of a known, noncooperative, tumbling target spacecraft in a close-proximity rendezvous scenario. The UKF estimates the target's orbit and attitude relative to the servicer based on the pose information provided by a multi-task Convolutional Neural Network (CNN) from incoming monocular images of the target. In order to enable reliable tracking, the process noise covariance matrix of the UKF is tuned online using adaptive state noise compensation which leverages a newly developed closed-form process noise model for relative attitude dynamics. This paper also introduces the Satellite Hardware-In-the-loop Rendezvous Trajectories (SHIRT) dataset to enable comprehensive analyses of the performance and robustness of the proposed pipeline. SHIRT comprises the labeled images of two representative rendezvous trajectories in low Earth orbit created using both a graphics renderer and a robotic testbed. Specifically, the CNN is solely trained on synthetic data, whereas functionality and performance of the complete navigation pipeline are evaluated on real images from the robotic testbed. The proposed UKF is evaluated on SHIRT and is shown to have sub-decimeter-level position and degree-level orientation errors at steady-state.
description: Accepted to AIAA Journal of Guidance, Control, and Dynamics. Updated derivation of Section IV.B and experiments
Unified non-equilibrium simulation methodology for flow through nanoporous carbon membrane
Creators: name: Monet, Geoffrey
name: Bocquet, Marie-Laure
name: Bocquet, Lydéric
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The emergence of new nanoporous materials, based e.g. on 2D materials, offers new avenues for water filtration and energy. There is accordingly a need to investigate the molecular mechanisms at the root of the advanced performances of these systems in terms of nanofluidic and ionic transport. In this work, we introduce a novel unified methodology for Non-Equilibrium classical Molecular Dynamic simulations (NEMD), allowing to apply likewise pressure, chemical potential and voltage drops across nanoporous membranes and quantifying the resulting observables characterizing confined liquid transport under such external stimuli. We apply the NEMD methodology to study a new type of synthetic Carbon NanoMembranes (CNM), which have recently shown outstanding performances for desalination, keeping high water permeability while maintaining full salt rejection. The high water permeance of CNM, as measured experimentally, is shown to originate in prominent entrance effects associated with negligible friction inside the nanopore. Beyond, our methodology allows to fully calculate the symmetric transport matrix and the cross-phenomena such as electro-osmosis, diffusio-osmosis, streaming currents, etc. In particular, we predict a large diffusio-osmotic current across the CNM pore under concentration gradient, despite the absence of surface charges. This suggests that CNMs are outstanding candidates as alternative, scalable membranes for osmotic energy harvesting.
description: 13 pages, 16 figures, submitted to J. Chem Phys
The Minimum Halo Mass for Star Formation at z = 6 - 8
Creators: name: Finlator, K.
name: Prescott, M. K. M.
name: Oppenheimer, B. D.
name: Davé, R.
name: Zackrisson, E.
name: Livermore, R. C.
name: Finkelstein, S. L.
name: Thompson, R.
name: Huang, S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Recent analysis of strongly-lensed sources in the Hubble Frontier Fields indicates that the rest-frame UV luminosity function of galaxies at $z=$6--8 rises as a power law down to $M_\mathrm{UV}=-15$, and possibly as faint as -12.5. We use predictions from a cosmological radiation hydrodynamic simulation to map these luminosities onto physical space, constraining the minimum dark matter halo mass and stellar mass that the Frontier Fields probe. While previously-published theoretical studies have suggested or assumed that early star formation was suppressed in halos less massive than $10^9$--$10^{11} M_\odot$, we find that recent observations demand vigorous star formation in halos at least as massive as (3.1, 5.6, 10.5)$\times10^9 M_\odot$ at $z=(6,7,8)$. Likewise, we find that Frontier Fields observations probe down to stellar masses of (8.1, 18, 32)$\times10^6 M_\odot$; that is, they are observing the likely progenitors of analogues to Local Group dwarfs such as Pegasus and M32. Our simulations yield somewhat different constraints than two complementary models that have been invoked in similar analyses, emphasizing the need for further observational constraints on the galaxy-halo connection.
description: 8 pages, 5 figures, re-submitted to MNRAS after incorporating referee's comments
Robot Control for Simultaneous Impact Tasks through Time-Invariant Reference Spreading
Creators: name: van Steen, Jari J.
name: van de Wouw, Nathan
name: Saccon, Alessandro
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: Systems and Control (eess.SY)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: With the goal of enabling the exploitation of impacts in robotic manipulation, a new framework is presented for control of robotic manipulators that are tasked to execute nominally simultaneous impacts. In this framework, we employ tracking of time-invariant reference vector fields corresponding to the ante- and post-impact motion, increasing its applicability over similar conventional tracking control approaches. The ante- and post-impact references are coupled through a rigid impact map, and are extended to overlap around the area where the impact is expected to take place, such that the reference corresponding to the actual contact state of the robot can always be followed. As a sequence of impacts at the different contact points will typically occur, resulting in uncertainty of the contact mode and unreliable velocity measurements, a new interim control mode catered towards time-invariant references is formulated. In this mode, a position feedback signal is derived from the ante-impact velocity reference, which is used to enforce sustained contact in all contact points without using velocity feedback. With an eye towards real implementation, the approach is formulated using a QP control framework, and is validated using numerical simulations both on a rigid robot with a hard inelastic contact model and on a realistic robot model with flexible joints and compliant partially elastic contact model.
description: 8 pages, 6 figures. Submitted for publication to the IEEE American Control Conference (ACC) 2023
Reinforcement Learning Generation of 4-Qubits Entangled States
Creators: name: Giordano, Sara
name: Martin-Delgado, Miguel A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We have devised an artificial intelligence algorithm with machine reinforcement learning (Q-learning) to construct remarkable entangled states with 4 qubits. This way, the algorithm is able to generate representative states for some of the 49 true SLOCC classes of the four-qubit entanglement states. In particular, it is possible to reach at least one true SLOCC class for each of the nine entanglement families. The quantum circuits synthesized by the algorithm may be useful for the experimental realization of these important classes of entangled states and to draw conclusions about the intrinsic properties of our universe. We introduce a graphical tool called the state-link graph (SLG) to represent the construction of the Quality matrix (Q-matrix) used by the algorithm to build a given objective state belonging to the corresponding entanglement class. This allows us to discover the necessary connections between specific entanglement features and the role of certain quantum gates that the algorithm needs to include in the quantum gate set of actions. The quantum circuits found are optimal by construction with respect to the quantum gate-set chosen. These SLGs make the algorithm simple, intuitive and a useful resource for the automated construction of entangled states with a low number of qubits.
description: Tex file, color figures
Precision velocimetry planet hunting with PARAS: Current performance and lessons to inform future extreme precision radial velocity instruments
Creators: name: Roy, Arpita
name: Chakraborty, Abhijit
name: Mahadevan, Suvrath
name: Chaturvedi, Priyanka
name: Prasad, Neelam J. S. S. V.
name: Shah, Vishal
name: Pathan, F. M.
name: Anandarao, B. G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: PARAS is a fiber-fed stabilized high-resolution cross-dispersed echelle spectrograph, located on the 1.2 m telescope in Mt. Abu India. Designed for exoplanet detection, PARAS is capable of single-shot spectral coverage of 3800 - 9600 A, and currently achieving radial velocity (RV) precisions approaching ~1 m/s over several months using simultaneous ThAr calibration. As such, it is one of the few dedicated stabilized fiber-fed spectrographs on small (1-2 m) telescopes that are able to fill an important niche in RV follow-up and stellar characterization. The success of ground-based RV surveys is motivating the push into extreme precisions, with goals of ~10 cm/s in the optical and <1 m/s in the near-infrared (NIR). Lessons from existing instruments like PARAS are invaluable in informing hardware design, providing pipeline prototypes, and guiding scientific surveys. Here we present our current precision estimates of PARAS based on observations of bright RV standard stars, and describe the evolution of the data reduction and RV analysis pipeline as instrument characterization progresses and we gather longer baselines of data. Secondly, we discuss how our experience with PARAS is a critical component in the development of future cutting edge instruments like (1) the Habitable Zone Planet Finder (HPF), a NIR spectrograph optimized to look for planets around M dwarfs, scheduled to be commissioned on the Hobby Eberly Telescope in 2017, and (2) the NEID optical spectrograph, designed in response to the NN-EXPLORE call for an extreme precision Doppler spectrometer (EPDS) for the WIYN telescope. In anticipation of instruments like TESS and GAIA, the ground-based RV support system is being reinforced. We emphasize that instruments like PARAS will play an intrinsic role in providing both complementary follow-up and battlefront experience for these next generation of precision velocimeters.
description: 9 pages, 6 figures, published in Proc. of SPIE Astronomical Telescopes + Instrumentation 2016
Swarm equilibria in domains with boundaries
Creators: name: Fetecau, Razvan C.
name: Kovacic, Mitchell
Publisher: name: arXiv
Year: 2016
Subjects: subject: Pattern Formation and Solitons (nlin.PS)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: We study equilibria in domains with boundaries for a first-order aggregation model that includes social interactions and exogenous forces. Such equilibrium solutions can be connected or disconnected, the latter consisting in a delta concentration on the boundary and a free swarm component in the interior of the domain. Equilibria are stationary points of an energy functional, and stable configurations are local minimizers of this functional. We find a one-parameter family of disconnected equilibrium configurations which are not energy minimizers; the only stable equilibria are the connected states. Nevertheless, we demonstrate that in certain cases the dynamical evolution, along the gradient flow of the energy functional, tends to overwhelmingly favour the formation of (unstable) disconnected equilibria.
description: 39 pages, 15 figures (multiple images per figure)
Enhanced metallic properties of SrRuO3 thin films via kinetically controlled pulsed laser epitaxy
Creators: name: Thompson, J.
name: Nichols, J.
name: Lee, S.
name: Ryee, S.
name: Gruenewald, J. H.
name: Connell, J. G.
name: Souri, M.
name: Johnson, J. M.
name: Hwang, J.
name: Han, M. J.
name: Lee, H. N.
name: Kim, D. -W.
name: Seo, S. S. A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Other Condensed Matter (cond-mat.other)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Metal electrodes are a universal element of all electronic devices. Conducting SrRuO3 (SRO) epitaxial thin films have been extensively used as electrodes in complex-oxide heterostructures due to good lattice mismatches with perovskite substrates. However, when compared to SRO single crystals, SRO thin films have shown reduced conductivity and Curie temperatures (T_C), which can lead to higher Joule heating and energy loss in the devices. Here, we report that high-quality SRO thin films can be synthesized by controlling the plume dynamics and growth rate of pulsed laser epitaxy (PLE) with real-time optical spectroscopic monitoring. The SRO thin films grown under the kinetically controlled conditions, down to ca. 16 nm in thickness, exhibit both enhanced conductivity and T_C as compared to bulk values, due to their improved stoichiometry and a strain-mediated increase of the bandwidth of Ru 4d electrons. This result provides a direction for enhancing the physical properties of PLE-grown thin films and paves a way for improved device applications.
description: 8 pages, 4 figures, 1 table
Calibrating the momentum width of a trapped Bose-Einstein condensate by one-dimensional optical lattice pulse sequences
Creators: name: Liang, Angang
name: Zhou, Shuyu
name: Xie, Yu
name: Huang, Mingshan
name: Fang, Su
name: Wang, Bin
name: Liu, Liang
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We experimentally measured the ultra-narrow momentum width of an optical trapped Bose-Einstein condensate (BEC) in situ based on matter-wave interference, which validates our previous theoretical work [arXiv: 2205.02416]. By sweeping the interval of double stand-wave pulses, the BEC wave packet was splitted into different diffraction orders and then we counted the oscillation curve of the population of zero-momentum state to calibrate the momentum width. Compared with our simplified theory, we observed an accelerated evolution of interference fringes in time-domain. We evaluated this interference process minutely by numerically calculating the Gross-Pitaevskii equation and using Wigner function to intuitively demonstrate the influence of the external potential and nonlinear term. We confirmed that the reduction of interference fringe evolution period actually originates from the synergistic cooperation of the mean-field interaction of the BEC and spatial density modulation caused by the interference between different momentum states. Our approach could be generalized to other ultra-cold atomic gases with different momentum distributions, and in principle a single shot can obtain the result. This quantum thermometry is particularly suitable for momentum width calibration in practical deep cooling experiments, while for atomic samples at pK level the mean-field interaction can be safely ignored.
description: 12 pages, 7 figures
Uncorrelated Amplitude and Frequency Variations of the Harmonics in SX Phoenicis Star XX Cygni
Creators: name: Niu, Jia-Shu
name: Liu, Yue
name: Xue, Hui-Fang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Harmonics are quite common in pulsating stars, and they are always considered to mimic the behaviors of their independent parent pulsation modes and not taken as the key information for asteroseismology. Here, we report an SX Phoenicis star XX Cygni, whose periodogram is dominated by the fundamental frequency $f_{0} = 7.41481 \pm 0.00004\ \mathrm{cd}^{-1}$ and its 19 harmonics. According to the analysis of the archival data from \TESS, we find that both the amplitudes and frequencies of the fundamental mode and the harmonics vary within TESS Sectors 14-17 and 54-57, which might be caused by the contamination by neighbouring stars. What is more interesting is that, the harmonics show significantly uncorrelated amplitude and frequency variations over time. Some possible origins and interesting issues are proposed to scheme the further research of this hidden corner in current asteroseismology.
description: 11 pages, 6 figures, 2 tables. AJ published
Analytical model for release calculations in solid thin-foils ISOL targets
Creators: name: Egoriti, Luca
name: Boeckx, Stef
name: Ghys, Lars
name: Houngbo, Donald
name: Popescu, Lucia
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: A detailed analytical model has been developed to simulate isotope-release curves from thin-foils ISOL targets. It involves the separate modelling of diffusion and effusion inside the target. The former has been modelled using both first and second Fick's law. The latter, effusion from the surface of the target material to the end of the ionizer, was simulated with the Monte Carlo code MolFlow+. The calculated delay-time distribution for this process was then fitted using a double-exponential function. The release curve obtained from the convolution of diffusion and effusion shows good agreement with experimental data from two different target geometries used at ISOLDE. Moreover, the experimental yields are well reproduced when combining the release fraction with calculated in-target production.
description: accepted for publication in Nuclear Inst. and Methods in Physics Research A
Cosmological Perturbations Engendered by Discrete Relativistic Species
Creators: name: Brilenkov, Maksym
name: Canay, Ezgi
name: Eingorn, Maxim
Publisher: name: arXiv
Year: 2022
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: Within the extension of the $Λ$CDM model, allowing for the presence of neutrinos or warm dark matter, we develop the analytical cosmological perturbation theory. It covers all spatial scales where the weak gravitational field regime represents a valid approximation. Discrete particles - the sources of the inhomogeneous gravitational field - may be relativistic. Similarly to the previously investigated case of nonrelativistic matter, the Yukawa interaction range is naturally incorporated into the first-order scalar metric corrections.
description: 5 pages, no figures
Exploring the convergence of general education and vocational education
Creators: name: Sheed, Jennifer
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Magnetic field dependence of the internal quality factor and noise performance of lumped-element kinetic inductance detectors
Creators: name: Flanigan, Daniel
name: Johnson, Bradley R.
name: Abitbol, Maximilian H.
name: Bryan, Sean
name: Cantor, Robin
name: Day, Peter K.
name: Jones, Glenn
name: Mauskopf, Philip
name: McCarrick, Heather
name: Miller, Amber
name: Zmuidzinas, Jonas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Superconductivity (cond-mat.supr-con)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: We present a technique for increasing the internal quality factor of kinetic inductance detectors (KIDs) by nulling ambient magnetic fields with a properly applied magnetic field. The KIDs used in this study are made from thin-film aluminum, they are mounted inside a light-tight package made from bulk aluminum, and they are operated near $150 \, \mathrm{mK}$. Since the thin-film aluminum has a slightly elevated critical temperature ($T_\mathrm{c} = 1.4 \, \mathrm{K}$), it therefore transitions before the package ($T_\mathrm{c} = 1.2 \, \mathrm{K}$), which also serves as a magnetic shield. On cooldown, ambient magnetic fields as small as approximately $30 \, \mathrm{μT}$ can produce vortices in the thin-film aluminum as it transitions because the bulk aluminum package has not yet transitioned and therefore is not yet shielding. These vortices become trapped inside the aluminum package below $1.2 \, \mathrm{K}$ and ultimately produce low internal quality factors in the thin-film superconducting resonators. We show that by controlling the strength of the magnetic field present when the thin film transitions, we can control the internal quality factor of the resonators. We also compare the noise performance with and without vortices present, and find no evidence for excess noise beyond the increase in amplifier noise, which is expected with increasing loss.
description: 5 pages, 4 figures
Real-Time Navigation for Autonomous Surface Vehicles In Ice-Covered Waters
Creators: name: de Schaetzen, Rodrigue
name: Botros, Alexander
name: Gash, Robert
name: Murrant, Kevin
name: Smith, Stephen L.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Vessel transit in ice-covered waters poses unique challenges in safe and efficient motion planning. When the concentration of ice is high, it may not be possible to find collision-free trajectories. Instead, ice can be pushed out of the way if it is small or if contact occurs near the edge of the ice. In this work, we propose a real-time navigation framework that minimizes collisions with ice and distance travelled by the vessel. We exploit a lattice-based planner with a cost that captures the ship interaction with ice. To address the dynamic nature of the environment, we plan motion in a receding horizon manner based on updated vessel and ice state information. Further, we present a novel planning heuristic for evaluating the cost-to-go, which is applicable to navigation in a channel without a fixed goal location. The performance of our planner is evaluated across several levels of ice concentration both in simulated and in real-world experiments.
description: 7 pages, 8 figures