cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Application of Management Control System in Ethiopian Commercial Banks
Creators: name: Eshetie, Ayichew
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2011

description: Banking sector is one of the most successful financial institutions in Ethiopia; however, there is virtually no formidable study on management control system about this sector. The increasing knowledge and understanding on the application of management control system, for the area in which this research was undertaken by benchmarking of the same research undertaken in other country, were taken as the major initiators of this study and were the rationale to the research. This study focused only the application of management control system in Ethiopia Commercial Banks even if there were different managerial issues in the banking industry at the head and branch offices as well. An institution based cross sectional descriptive study with analytic components was conducted in Ethiopian commercial banks which are functioned at Addis Ababa. The study employed both quantitative and qualitative study approaches. Study population for the survey was employees, officers and mangers of the banks. Besides, for the qualitative part, key informant interviews were conducted with mangers and officers of the banks. A questionnaire with five Likert scale for the survey which is mainly used for quantitative part, and Semi-structured interview guide for the qualitative were used as data collection tools. SPSS version 19 for windows was employed to perform statistical analysis. Findings were displayed using tables, and pie-charts. The regression results show that strategic planning and management; and performance measurement have positive and statistical significant contribution on management control system of Ethiopian commercial banks .this is as similar result with (Sinikka 2007).Besides, the commercial banks are competing mainly in service and many of them adapting differentiation strategy. The priority of the majority of commercial banks is customer retention. Commercial banks are encouraging employees to upgrade their knowledge and skill on the basis of experience or service offer to the bank. However, some problems were also there; human capital, benefit entitlement, liquidity and responsibility center. Therefore, the commercial banks need to give due attention for these problems, giving and preparing continuous training for employees and evaluating training results. Key words: Management control system, commercial bank, budgeting system, performance measurement, cost accounting and service pricing, decision making, compensation and benefit
Perpetual Observational Studies: New strategies to support efficient implementation of observational studies and randomized trials in the infectious diseases arena
Creators: name: Hassoun-Kheir, N.
name: van Werkhoven, C. H.
name: Dunning, J.
name: Jaenisch, T.
name: van Beek, J.
name: Bielicki, J.
name: Butler, C.
name: Francois, B.
name: Harbarth, S.
name: Padilla, A. C. Hernandez
name: Horby, P.
name: Koopmans, M.
name: Lee, J.
name: Rodriguez-Baño, J.
name: Tacconelli, E.
name: Themistocleous, Y.
name: van der Velden, A. W.
name: Bonten, M.
name: Goossens, H.
name: de Kraker, M. E. A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Methodology (stat.ME)
subject: FOS: Computer and information sciences

description: The increasing threat of emerging infectious diseases and antimicrobial resistance requires more efficient, high-quality research. Perpetual Observational Studies (POS) nested within a clinical research network can improve planning, quality and efficiency of interventional and observational studies, although real-life benefits and challenges need to be assessed. Ecraid (European Clinical Research Alliance on Infectious Diseases) has initiated POS and will monitor the impact for five specific infectious syndromes.
description: 16 pages, 2 tables
Local buckling of a thin-walled channel
Creators: name: Lau, Yuen Chun.
Publisher: name: Monash University
Year: 2022

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.
Phenomenological inflationary model in Supersymmetric Quantum Cosmology
Creators: name: Martínez-Pérez, N. E.
name: Ramírez, C.
name: Báez, V. M. Vázquez
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider the effective evolution of a phenomenological model from FLRW supersymmetric quantum cosmology with a scalar field. The scalar field acts as a clock and inflaton. We examine a family of simple superpotentials that produce an inflation whose virtual effect on inhomogeneous fluctuations shows very good agreement with PLANCK observational evidence for the tensor-to-scalar ratio and the scalar spectral index.
description: 14 pages, 6 figures. arXiv admin note: text overlap with arXiv:2104.12914
Topological spin ordering via Chern-Simons superconductivity
Creators: name: Sedrakyan, Tigran A.
name: Galitski, Victor M.
name: Kamenev, Alex
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We use the Chern-Simons (CS) fermion representation of s =1/2 spin operators to construct topological, long-range magnetically ordered states of interacting two-dimensional (2D) quantum spin models. We show that the fermion-fermion interactions mediated by the dynamic CS flux attachment may give rise to Cooper pairing of the fermions. Specifically, in an XY model on the honeycomb lattice, this construction leads to a "CS superconductor," which belongs to a topologically non-trivial in 2D symmetry class DIII, with particle-hole and time-reversal symmetries. It is shown that in the original spin language, this state corresponds to a symmetry protected topological state, which coexists with a magnetic long-range order. We discuss physical manifestations of the topological character of the corresponding state and requirements for models that could host it.
description: Main text: 5 pages, 2 figures. Supplement: 2 pages, 1 figure
Front propagation in ultrastable glasses is dynamically heterogeneous
Creators: name: Herrero, Cecilia
name: Ediger, Mark D.
name: Berthier, Ludovic
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Upon heating, ultrastable glassy films transform into liquids via a propagating equilibration front, resembling the heterogeneous melting of crystals. A microscopic understanding of this robust phenomenology is however lacking because experimental resolution is limited. We simulate the heterogeneous transformation kinetics of ultrastable configurations prepared using the swap Monte Carlo algorithm, thus allowing direct comparison with experiments. We resolve the liquid-glass interface both in space and time as well as the underlying particle motion responsible for its propagation. We perform a detailed statistical analysis of the interface geometry and kinetics over a broad range of temperatures. We show that the dynamic heterogeneity of the bulk liquid is passed on to the front which propagates heterogeneously in space and intermittently in time. This observation allows us to relate the averaged front velocity to the equilibrium diffusion coefficient of the liquid. We suggest that an experimental characterisation of the interface geometry during the heterogeneous devitrification of ultrastable glassy films would provide direct experimental access to the long-sought characteristic lengthscale of dynamic heterogeneity in bulk supercooled liquids.
Dynamical process of a bit-width reduced Ising model with simulated annealing
Creators: name: Kikuchi, Shuta
name: Togawa, Nozomu
name: Tanaka, Shu
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Ising machines have attracted attention as efficient solvers for combinatorial optimization problems, which are formulated as ground-state (lowest-energy) search problems of the Ising model. Due to the limited bit-width of coefficients on Ising machines, the Ising model must be transformed into a bit-width reduced (BWR) Ising model. According to previous research, the bit-width reduction method, which adds auxiliary spins, ensures that the ground state of the BWR Ising model is theoretically the same as the Ising model before bit-width reduction (original Ising model). However, while the dynamical process is closely related to solution accuracy, how the BWR Ising model progresses towards the ground state remains to be elucidated. Therefore, we compared the dynamical processes of these models using simulated annealing (SA). Our findings reveal significant differences in the dynamical process across models. Analysis from the viewpoint of statistical mechanics found that the BWR Ising model has two characteristic properties: an effective temperature and a slow relaxation. These properties alter the temperature schedule and spin flip probability in the BWR Ising model, leading to differences in the dynamical process. Therefore, to obtain the same dynamical process as the original Ising model, we proposed SA parameters for the BWR Ising model. We demonstrated the proposed SA parameters using a square lattice Ising model, in which all coefficients were set uniformly to the same positive values or randomly. Our experimental evaluations demonstrated that the dynamical process of the BWR and original Ising model became closer.
description: 15 pages, 17 figures
Assigning Shadow Prices to Synthetic Inertia and Frequency Response Reserves from Renewable Energy Sources
Creators: name: Badesa, Luis
name: Matamala, Carlos
name: Zhou, Yujing
name: Strbac, Goran
Publisher: name: arXiv
Year: 2022
Subjects: subject: Systems and Control (eess.SY)
subject: Optimization and Control (math.OC)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Mathematics

description: Modern electricity grids throughout the world, particularly in islands such as Great Britain, face a major problem on the road to decarbonisation: the significantly reduced level of system inertia due to integration of Renewable Energy Sources (RES). Given that most RES such as wind and solar are decoupled from the grid through power electronics converters, they do not naturally contribute to system inertia. However, RES could support grid stability through appropriately controlling the converters, but currently no market incentives exist for RES to provide this support. In this paper we develop a methodology to optimally clear a market of ancillary services for frequency control, while explicitly considering the participation of grid-forming and grid-following inverter-based technologies. We propose a mathematical framework that allows to compute shadow prices for ancillary services offered by a pool of diverse providers: synchronous and synthetic inertia, enhanced frequency response (e.g. from curtailed RES) and traditional primary frequency response (e.g. by thermal generators). Several case studies are run on a simplified Great Britain system, to illustrate the applicability and benefits of this pricing scheme.
description: IEEE Transactions on Sustainable Energy
Line-driven disk wind model for ultra-fast outflows in active galactic nuclei -- Scaling with luminosity
Creators: name: Nomura, Mariko
name: Ohsuga, Ken
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: In order to reveal the origin of the ultra-fast outflows (UFOs) that are frequently observed in active galactic nuclei (AGNs), we perform two-dimensional radiation hydrodynamics simulations of the line-driven disk winds, which are accelerated by the radiation force due to the spectral lines. The line-driven winds are successfully launched for the range of $M_{\rm BH}=10^{6-9}M_\odot$ and $\varepsilon$=0.1-0.5, and the resulting mass outflow rate ($\dot{M_{\rm w}}$), momentum flux ($\dot{p_{\rm w}}$), and kinetic luminosity ($\dot{E_{\rm w}}$) are in the region containing 90% of the posterior probability distribution in the $\dot M_{\rm w}$-$L_{\rm bol}$ plane, $\dot p_{\rm w}$-$L_{\rm bol}$ plane, and $\dot E_{\rm w}$-$L_{\rm bol}$ plane shown in Gofford et al., where $M_{\rm BH}$ is the black hole mass, $\varepsilon$ is the Eddington ratio, and $L_{\rm bol}$ is the bolometric luminosity. The best-fitting relations in Gofford et al., $d\log\dot{M_{\rm w}}/d\log{L_{\rm bol}}\sim 0.9$, $d\log\dot{p_{\rm w}}/d\log{L_{\rm bol}}\sim 1.2$, and $d\log\dot{E_{\rm w}}/d\log{L_{\rm bol}}\sim 1.5$, are roughly consistent with our results, $d\log\dot{M_{\rm w}}/d\log{L_{\rm bol}}\sim 9/8$, $d\log\dot{p_{\rm w}}/d\log{L_{\rm bol}}\sim 10/8$, and $d\log\dot{E_{\rm w}}/d\log{L_{\rm bol}}\sim 11/8$. In addition, our model predicts that no UFO features are detected for the AGNs with $\varepsilon \lesssim 0.01$, since the winds do not appear. Also, only AGNs with $M_{\rm BH} \lesssim 10^8 M_\odot$ exhibit the UFOs when $\varepsilon \sim 0.025$. These predictions nicely agree with the X-ray observations (Gofford et al.). These results support that the line-driven disk wind is the origin of the UFOs.
description: 8 pages, 6 figures, accepted for publication in MNRAS
Simplified models of diffusion in radially-symmetric geometries
Creators: name: Filippini, Luke P.
name: Simpson, Matthew J.
name: Carr, Elliot J.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: We consider diffusion-controlled release of particles from $d$-dimensional radially-symmetric geometries. A quantity commonly used to characterise such diffusive processes is the proportion of particles remaining within the geometry over time, denoted as $P(t)$. The stochastic approach for computing $P(t)$ is time-consuming and lacks analytical insight into key parameters while the continuum approach yields complicated expressions for $P(t)$ that obscure the influence of key parameters and complicate the process of fitting experimental release data. In this work, to address these issues, we develop several simple surrogate models to approximate $P(t)$ by matching moments with the continuum analogue of the stochastic diffusion model. Surrogate models are developed for homogeneous slab, circular, annular, spherical and spherical shell geometries with a constant particle movement probability and heterogeneous slab, circular, annular and spherical geometries, comprised of two concentric layers with different particle movement probabilities. Each model is easy to evaluate, agrees well with both stochastic and continuum calculations of $P(t)$ and provides analytical insight into the key parameters of the diffusive transport system: dimension, diffusivity, geometry and boundary conditions.
description: 22 pages, 3 figures, accepted version
The Effect of Debt Financing on Profitability of Commercial Banks in Ethiopia
Creators: name: Lambebo, Tamirat
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2015

description: This study was conducted on the effects of debt financing on profitability of Commercial Banks in Ethiopia. For this purpose, sample of eight commercial banks was studied from all commercial Banks engaged in commercial banking activates. The study period covered twelve years from the years (2002-2013). The dependent variable is return on asset (ROA) used to measure the profitability of commercial banks and the independent variable are debt to asset ratio, debt to equity ratio and interest coverage ratio to measure the level of debt on capital structure of the institution. To ensure the accuracy of the results of the regression model used one control variable that is firm size. To address the main objectives of this study and to collect accurate information mainly used secondary data. Primary data was used to support the secondary data. As the result, the research approaches are mixed research approach. The data analyzed by using panel data analysis technique. The descriptive statistics and the correlation analysis were discussed, followed by the diagnostic test, which is necessary to fulfilling the assumption of the classical linear regression model. Then, a fixed effect regression output result was presented and the results of the regression outputs were discussed. Finally, discussion result indicates that all independent variables had positive relationship with profitability and statistically significant. Keywords: Debt Financing, profitability, return on asset, debt to asset ratio, debt to equity ratio, interest coverage ratio and firm size
SPT0346-52: Negligible AGN Activity in a Compact, Hyper-starburst Galaxy at z = 5.7
Creators: name: Ma, Jingzhe
name: Gonzalez, A. H.
name: Vieira, J. D.
name: Aravena, M.
name: Ashby, M. L. N.
name: Bethermin, M.
name: Bothwell, M. S.
name: Brandt, W. N.
name: de Breuck, C.
name: Carlstrom, J. E.
name: Chapman, S. C.
name: Gullberg, B.
name: Hezaveh, Y.
name: Litke, K.
name: Malkan, M.
name: Marrone, D. P.
name: McDonald, M.
name: Murphy, E. J.
name: Spilker, J. S.
name: Sreevani, J.
name: Stark, A. A.
name: Strandet, M.
name: Wang, S. X.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present Chandra ACIS-S and ATCA radio continuum observations of the strongly lensed dusty, star-forming galaxy SPT-S J034640-5204.9 (hereafter SPT0346-52) at $z$ = 5.656. This galaxy has also been observed with ALMA, HST, Spitzer, Herschel, APEX, and the VLT. Previous observations indicate that if the infrared (IR) emission is driven by star formation, then the inferred lensing-corrected star formation rate ($\sim$ 4500 $M_{\sun}$ yr$^{-1}$) and star formation rate surface density $Σ_{\rm SFR}$ ($\sim$ 2000 $M_{\sun} {yr^{-1}} {kpc^{-2}}$) are both exceptionally high. It remained unclear from the previous data, however, whether a central active galactic nucleus (AGN) contributes appreciably to the IR luminosity. The {\it Chandra} upper limit shows that SPT0346-52 is consistent with being star-formation dominated in the X-ray, and any AGN contribution to the IR emission is negligible. The ATCA radio continuum upper limits are also consistent with the FIR-to-radio correlation for star-forming galaxies with no indication of an additional AGN contribution. The observed prodigious intrinsic IR luminosity of (3.6 $\pm$ 0.3) $\times$ 10$^{13}$ $L_{\sun}$ originates almost solely from vigorous star formation activity. With an intrinsic source size of 0.61 $\pm$ 0.03 kpc, SPT0346-52 is confirmed to have one of the highest $Σ_{SFR}$ of any known galaxy. This high $Σ_{SFR}$, which approaches the Eddington limit for a radiation pressure supported starburst, may be explained by a combination of very high star formation efficiency and gas fraction.
description: 8 pages, 6 figures, accepted for publication in ApJ
The Nilpotent Structure of Open-Closed String Field Theory
Creators: name: Maccaferri, Carlo
name: Ruffino, Alberto
name: Vošmera, Jakub
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this note we revisit the homotopy-algebraic structure of oriented bosonic open-closed string field theory and we give a new compact formulation in terms of a single cyclic open-closed coderivation which defines a single nilpotent structure describing the consistency of generic open-closed color-ordered off-shell amplitudes with arbitrary number of boundaries and at arbitrary genus.
description: 23 pages. V2: minor presentation improvements
Estrella distante, de Roberto Bolaño. Píldora audiovisual
Creators: name: Jiménez, Francisca Noguerol
name: Elvira-Navarro, Andrea
name: Sánchez-Aparicio, Vega
name: Vidal, Borja Cano
name: García, José Antonio Paniagua
Publisher: name: Zenodo
Year: 2022

description: Material docente elaborado en el seno del proyecto de Innovación Docente «Elaboración de píldoras audiovisuales para la enseñanza de la literatura hispanoamericana» (ID2021/076) concedido por la Universidad de Salamanca durante el curso académico 2021/2022.
Determinants of Liquidity of Commercial Banks of Ethiopia
Creators: name: Fekadu, Alemayehu
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2016

description: The purpose of this research is to identify the factors significant to explain Ethiopian commercial Banks liquidity. This study has categorized the independent factors into bank specific factors and macroeconomic factors. The bank specific factors include Bank Size, Capital Adequacy, Profitability, Non-Performing Loans, and Loan Growth while the macroeconomic factors include Gross Domestic Product, General Inflation and National bank Bill. The panel data was used for the sample of eight commercial banks in Ethiopia from 2002 to 2013 year and estimated using Fixed Effect Model(FEM), data was present by using descriptive statistics and the balanced correlation and regression analysis for liquidity ratios was conducted. The findings of the study show that capital strength and profitability had statistically significant and positive relationship with banks' liquidity. On the other hand, loan growth and national bank bill had a negative and statistically significant relationship with banks' liquidity. However, the relationship for inflation, non-performing loans, bank size and gross domestic product were found to be statistically insignificant. The study suggests banks must have increase their outreach to tens of millions of people by openings up more and more branches every year through country, and have significantly improve their banking service by introducing new product and services like Agent banking, Mobile banking and Internet Banking through the application of modern technology. Moreover, banks in Ethiopia should not only be concerned about internal structures and policies, but they must consider both the government regulation and the macroeconomic environment together in developing strategies to improve the liquidity position of the banks. Key words: Ethiopian commercial banks, determinants of liquidity, liquidity ratios, liquidity risk, panel data regression analysis.
Dual Domain-Adversarial Learning for Audio-Visual Saliency Prediction
Creators: name: Fan, Yingzi
name: Han, Longfei
name: Zhang, Yue
name: Cheng, Lechao
name: Xia, Chen
name: Hu, Di
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Both visual and auditory information are valuable to determine the salient regions in videos. Deep convolution neural networks (CNN) showcase strong capacity in coping with the audio-visual saliency prediction task. Due to various factors such as shooting scenes and weather, there often exists moderate distribution discrepancy between source training data and target testing data. The domain discrepancy induces to performance degradation on target testing data for CNN models. This paper makes an early attempt to tackle the unsupervised domain adaptation problem for audio-visual saliency prediction. We propose a dual domain-adversarial learning algorithm to mitigate the domain discrepancy between source and target data. First, a specific domain discrimination branch is built up for aligning the auditory feature distributions. Then, those auditory features are fused into the visual features through a cross-modal self-attention module. The other domain discrimination branch is devised to reduce the domain discrepancy of visual features and audio-visual correlations implied by the fused audio-visual features. Experiments on public benchmarks demonstrate that our method can relieve the performance degradation caused by domain discrepancy.
description: Accepted by ACM MM workshop 2022(HCMA2022)
MeV-scale sterile neutrino decays at the Fermilab Short-Baseline Neutrino program
Creators: name: Ballett, Peter
name: Pascoli, Silvia
name: Ross-Lonergan, Mark
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Nearly-sterile neutrinos with masses in the MeV range and below would be produced in the beam of the Short-Baseline Neutrino (SBN) program at Fermilab. In this article, we study the potential for SBN to discover these particles through their subsequent decays in its detectors. We discuss the decays which will be visible at SBN in a minimal and non-minimal extension of the Standard Model, and perform simulations to compute the parameter space constraints which could be placed in the absence of a signal. We demonstrate that the SBN program can extend existing bounds on well constrained channels such as $N \rightarrow νl^+ l^-$ and $N \rightarrow l^\pm π^\mp$ while, thanks to the strong particle identification capabilities of liquid-Argon technology, also place bounds on often neglected channels such as $N \rightarrow νγ$ and $N \rightarrow νπ^0$. Furthermore, we consider the phenomenological impact of improved event timing information at the three detectors. As well as considering its role in background reduction, we note that if the light-detection systems in SBND and ICARUS can achieve nanosecond timing resolution, the effect of finite sterile neutrino mass could be directly observable, providing a smoking-gun signature for this class of models. We stress throughout that the search for heavy nearly-sterile neutrinos is a complementary new physics analysis to the search for eV-scale oscillations, and would extend the BSM program of SBN while requiring no beam or detector modifications.
description: 37 pages, 20 figures
title: Συμμετοχικές  διαδικασίες και ψηφιακή κατασκευή: Μια μελέτη για τη διεκδίκηση του δημόσιου χώρου
title: Participatory processes and digital fabrication: A study on re-claiming public spaces
Creators: name: Γουρουντη Ευχαρις
name: Ιβοπουλος Χρηστος
Publisher: name: Technical University of Crete
Year: 2023

description: Η παρούσα ερευνητική εργασία ξεκινά με αφετηρία την ανάλυση των διαφορετικών ταυτοτήτων του δημόσιου χώρου και τη σημασία τους για τους κατοίκους. Επικεντρώνεται στην ανάλυση “τακτικών” συμμετοχικών μεθοδολογιών και εργαλείων που οδηγούν σε χωρικές επεμβάσεις · υποστηρίζοντας πως οι επεμβάσεις, που ενσωματώνουν σύγχρονες τεχνικές ψηφιακής σχεδίασης και κατασκευής μπορούν να εξελιχθούν σε βιώσιμες λύσεις σχεδιασμού και παραγωγής χώρου.
Repetitive readout and real-time control of nuclear spin qubits in $^{171}$Yb atoms
Creators: name: Huie, William
name: Li, Lintao
name: Chen, Neville
name: Hu, Xiye
name: Jia, Zhubing
name: Sun, Won Kyu Calvin
name: Covey, Jacob P.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We demonstrate high fidelity repetitive projective measurements of nuclear spin qubits in an array of neutral ytterbium-171 ($^{171}$Yb) atoms. We show that the qubit state can be measured with a fidelity of 0.995(4) under a condition that leaves it in the state corresponding to the measurement outcome with a probability of 0.993(6) for a single tweezer and 0.981(4) averaged over the array. This is accomplished by near-perfect cyclicity of one of the nuclear spin qubit states with an optically excited state under a magnetic field of $B=58$ G, resulting in a bright/dark contrast of $\approx10^5$ during fluorescence readout. The performance improves further as $\sim1/B^2$. The state-averaged readout survival of 0.98(1) is limited by off-resonant scattering to dark states and can be addressed via post-selection by measuring the atom number at the end of the circuit, or during the circuit by performing a measurement of both qubit states. We combine projective measurements with high-fidelity rotations of the nuclear spin qubit via an AC magnetic field to explore several paradigmatic scenarios, including the non-commutivity of measurements in orthogonal bases, and the quantum Zeno mechanism in which measurements "freeze" coherent evolution. Finally, we employ real-time feedforward to repetitively deterministically prepare the qubit in the $+z$ or $-z$ direction after initializing it in an orthogonal basis and performing a projective measurement in the $z$-basis. These capabilities constitute an important step towards adaptive quantum circuits with atom arrays, such as in measurement-based quantum computation, fast many-body state preparation, holographic dynamics simulations, and quantum error correction.
The features of the Cosmic Web unveiled by the flip-flop field
Creators: name: Shandarin, Sergei F.
name: Medvedev, Mikhail V.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Understanding of the observed structure in the universe can be reached only in the theoretical framework of dark matter. N-body simulations are indispensable for the analysis of the formation and evolution of the dark matter web. Two primary fields - density and velocity fields - are used in most of studies. However dark matter provides two additional fields which are unique for collisionless media only. These are the multi- stream field in Eulerian space and flip-flop field in Lagrangian space. The flip-flop field represents the number of sign reversals of an elementary volume of each collisionless fluid element. This field can be estimated by counting the sign reversals of the Jacobian at each particle at every time step of the simulation. The Jacobian is evaluated by numerical differentiation of the Lagrangian submanifold, i.e., the three-dimensional dark matter sheet in the six-dimensional space formed by three Lagrangian and three Eulerian coordinates. We present the results of the statistical study of the evolution of the flip-flop field from z = 50 to the present time z = 0. A number of statistical characteristics show that the pattern of the flip-flop field remains remarkably stable from z = 30 to the present time. As a result the flip-flop field evaluated at z = 0 stores a wealth of information about the dynamical history of the dark matter web. In particular one of the most intriguing properties of the flip-flop is a unique capability to preserve the information about the merging history of dark matter haloes.
description: 19 pages, 25 figures, submitted to MNRAS
Spectrochemical analysis of non-conducting materials
Creators: name: Lomdahl, G. S.
Publisher: name: Monash University
Year: 2022

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.
Collateral coupling between superconducting resonators: Fast and high fidelity generation of qudit-qudit entanglement
Creators: name: Rosario, Pedro
name: Santos, Alan C.
name: Villas-Boas, Celso Jorge
name: Bachelard, Romain
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Superconducting circuits are highly controllable platforms to manipulate quantum states, which make them particularly promising for quantum information processing. We here show how the existence of a distance-independent interaction between microwave resonators coupled capacitively through a qubit offers a new control parameter toward this goal. This interaction is able to induce an idling point between resonant resonators, and its state-dependent nature allows one to control the flow of information between the resonators. The advantage of this scheme over previous one is demonstrated through the generation of high-fidelity NOON states between the resonators, with a lower number of operations than previous schemes. Beyond superconducting circuits, our proposal could also apply to atomic lattices with clock transitions in optical cavities, for example.
Impact of Internal Control Over Accounting Fraud in Public Enterprises in Addis Ababa
Creators: name: Negash, Tekalign
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2011

description: This study was conducted on impacts of internal control over accounting frauds in public enterprises in Addis Ababa. In general the paper uses sequential mixed methodology. Data are collected by using a self-administered survey which has both open ended and closed ended question. The questionnaire was given to both auditors and accountant who are found at different level. After feeding(inserting) the collected data in to SPSS for analyzing purpose; the researcher found that some of the company's internal controls are strong enough so that the possibility of accounting frauds which expected to happen is very low as compared to those surveyed public enterprises which are characterized by weak internal control. In general the reasons which plays a greater role in motivating and pushing peoples to commit accounting frauds includes personal finance al losses, living beyond once means, Lack of internal controls that prevent or detect fraud, ignorance and incapacity, and lack of an audit trial. The types of accounting frauds that is committed in the public enterprises are depend on the nature of the activity they undertakes and includes violating principles, manipulating of sales, manipulating of stocks(inventories), and manipulating revenues and expenses. Finally respondents agree that even if internal control is the best weapon to overcome accounting fraud related problems; it has to be supplemented by other issues like setting a code of conduct, training employees and consult about the ethical issues. Key words: Accounting frauds, Fraud triangle, Internal control
Breakdown of the Newton-Einstein Standard Gravity at Low Acceleration in Internal Dynamics of Wide Binary Stars
Creators: name: Chae, Kyu-Hyun
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: A gravitational anomaly is found at weak gravitational acceleration $g_{\rm{N}} < 10^{-9}$ m s$^{-2}$ from analyses of the dynamics of wide binary stars selected from the Gaia DR3 database that have accurate distances, proper motions, and reliably inferred stellar masses. Implicit high-order multiplicities are required and the multiplicity fraction is calibrated so that binary internal motions agree statistically with Newtonian dynamics at a high enough acceleration of $10^{-8}$ m s$^{-2}$. The observed sky-projected motions and separation are deprojected to the three-dimensional relative velocity $v$ and separation $r$ through a Monte Carlo method, and a statistical relation between the Newtonian acceleration $g_{\rm{N}} \equiv GM/r^2$ (where $M$ is the total mass of the binary system) and a kinematic acceleration $g \equiv v^2/r$ is compared with the corresponding relation predicted by Newtonian dynamics. The empirical acceleration relation at $< 10^{-9}$ m s$^{-2}$ systematically deviates from the Newtonian expectation. A gravitational anomaly parameter $δ_{\rm{obs-newt}}$ between the observed acceleration at $g_{\rm{N}}$ and the Newtonian prediction is measured to be: $δ_{\rm{obs-newt}}= 0.034\pm 0.007$ and $0.109\pm 0.013$ at $g_{\rm{N}}\approx10^{-8.91}$ and $10^{-10.15}$ m s$^{-2}$, from the main sample of 26,615 wide binaries within 200 pc. These two deviations in the same direction represent a $10σ$ significance. The deviation represents a direct evidence for the breakdown of standard gravity at weak acceleration. At $g_{\rm{N}}=10^{-10.15}$ m s$^{-2}$, the observed to Newton predicted acceleration ratio is $g_{\rm{obs}}/g_{\rm{pred}}=10^{\sqrt{2}δ_{\rm{obs-newt}}}=1.43\pm 0.06$. This systematic deviation agrees with the boost factor that the AQUAL theory predicts for kinematic accelerations in circular orbits under the Galactic external field.
description: A revised version of the published ApJ paper (2023, 952, 128) including corrections of Figures 12, 18, 20, and Equation (4) to be published in an erratum in press: all corrections are minor and have no impact on the contents or conclusion of the paper
Uncertainty Quantification of Sparse Travel Demand Prediction with Spatial-Temporal Graph Neural Networks
Creators: name: Zhuang, Dingyi
name: Wang, Shenhao
name: Koutsopoulos, Haris N.
name: Zhao, Jinhua
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Origin-Destination (O-D) travel demand prediction is a fundamental challenge in transportation. Recently, spatial-temporal deep learning models demonstrate the tremendous potential to enhance prediction accuracy. However, few studies tackled the uncertainty and sparsity issues in fine-grained O-D matrices. This presents a serious problem, because a vast number of zeros deviate from the Gaussian assumption underlying the deterministic deep learning models. To address this issue, we design a Spatial-Temporal Zero-Inflated Negative Binomial Graph Neural Network (STZINB-GNN) to quantify the uncertainty of the sparse travel demand. It analyzes spatial and temporal correlations using diffusion and temporal convolution networks, which are then fused to parameterize the probabilistic distributions of travel demand. The STZINB-GNN is examined using two real-world datasets with various spatial and temporal resolutions. The results demonstrate the superiority of STZINB-GNN over benchmark models, especially under high spatial-temporal resolutions, because of its high accuracy, tight confidence intervals, and interpretable parameters. The sparsity parameter of the STZINB-GNN has physical interpretation for various transportation applications.
description: Accepted by KDD 2022
Assessment of Capital Budgeting Decisions on Information System Investments; Evidence from Ethiopian Banks
Creators: name: Getachew, Mikiyas
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2016

description: Preliminary surveys and literatures on information system investments suggests a high increase on the level of investment, while there appears to be a lack of concrete empirical research on the area. In an attempt to explore the extent of this presumption, this research investigates the current state of IS investment and its process within Ethiopian banking institutions. Several theories and empirical outcomes were proposed to explain the investment pattern, appraisal techniques and post investment perception of IS adopters by the study subjects. To this end, the results of the study showed that information system investments are justified by information system heads, with the investment pattern focusing mainly on transaction processing systems (100%), management information systems (95%) and communication systems (63%). Furthermore, the study revealed the wide application of simple strategic investment appraisal methods, while the level of usage of discounted cash flow techniques and sophisticated analytical and integrated techniques being low. To illustrate, Strategic techniques were found to be very popular with Technical importance and SWOT analysis being used 100% and competitive advantage and critical success factor being used by 95% of the responding banks. Adding to this findings, the study showed the degree of perception investors have on the relative advantage brought by the system and the compatibility of the system with the organizations setting, in doing so the respondents showed a positive perception that was revealed with a mean value of 4.86 and 4.43, respectively: on a 1 to 5 scale where higher value represents higher agreement. Based on this findings, recommendations were made for a divers composition of professionals and appraisal techniques on IS investment justification process. Key Words: Information System, Information Technology, Investment Appraisal Techniques
Entangled coherent states and violations of Bell-CHSH inequalities
Creators: name: De Fabritiis, Philipe
name: Guedes, Fillipe M.
name: Peruzzo, Giovani
name: Sorella, Silvio P.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Three classes of entangled coherent states are employed to study the Bell-CHSH inequality. By using pseudospin operators in infinite dimensional Hilbert spaces, four dichotomic operators $(A,A',B,B')$ entering the inequality are constructed. For each class of coherent states, we compute the correlator $\langle ψ\vert A B + A' B + A B' - A' B' \vert ψ\rangle$, analyzing the set of parameters that leads to a Bell-CHSH inequality violation and, particularly, to the saturation of Tsirelson's bound.
description: 12 pages, 14 figures. Published in PLA
Primordial black holes from strong first-order phase transitions
Creators: name: Lewicki, Marek
name: Toczek, Piotr
name: Vaskonen, Ville
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study the formation of primordial black holes (PBHs) in strongly supercooled first-order phase transitions. The mechanism is based on the presence of remnants dominated by the false vacuum that scale slower with the expansion of the Universe than their surroundings where this energy was already converted into radiation. We compute the PBH formation from these remnants including the contribution from the false vacuum and the bubble walls, by estimating the collapse using the hoop conjecture and by considering both regions collapsing immediately when entering the horizon and sub-horizon regions that collapse as their compactness grows. We show that for exponential bubble nucleation rate, $Γ\propto e^{βt}$, the primordial black hole formation implies $β/H \gtrsim 3.8$, where $H$ denotes the Hubble rate, if the potential energy of the false vacuum is $ΔV \lesssim (10^{12} {\rm GeV})^4$, as otherwise a too large abundance of long-lived PBHs forms. The observed dark matter abundance can be formed in asteroid mass PBHs if $β/H \simeq 3.8$ and $10^5 {\rm GeV} \lesssim ΔV^{1/4} \lesssim 10^8 {\rm GeV}$. Finally, we consider also the effect of the second order correction to the exponential nucleation rate showing that the PBH abundance is mainly determined by the average radius of the true vacuum bubbles.
description: 15 pages, 6 figures. Minor changes to match the published version
Asteroseismic test of rotational mixing in low-mass white dwarfs
Creators: name: Istrate, A. G.
name: Fontaine, G.
name: Gianninas, A.
name: Grassitelli, L.
name: Marchant, P.
name: Tauris, T. M.
name: Langer, N.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We exploit the recent discovery of pulsations in mixed-atmosphere (He/H), extremely low-mass white dwarf precursors (ELM proto-WDs) to test the proposition that rotational mixing is a fundamental process in the formation and evolution of low-mass helium core white dwarfs. Rotational mixing has been shown to be a mechanism able to compete efficiently against gravitational settling, thus accounting naturally for the presence of He, as well as traces of metals such as Mg and Ca, typically found in the atmospheres of ELM proto-WDs. Here we investigate whether rotational mixing can maintain a sufficient amount of He in the deeper driving region of the star, such that it can fuel, through HeII-HeIII ionization, the observed pulsations in this type of stars. Using state-of-the-art evolutionary models computed with MESA, we show that rotational mixing can indeed explain qualitatively the very existence and general properties of the known pulsating, mixed-atmosphere ELM proto-WDs. Moreover, such objects are very likely to pulsate again during their final WD cooling phase.
description: accepted for publication in A&A Letters
Double universality of the transition in the supercritical state
Creators: name: Cockrell, Cillian
name: Trachenko, Kostya
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Universality aids consistent understanding of physical properties. This includes understanding the states of matter where a theory predicts how a property of a phase (solid, liquid, gas) changes with temperature or pressure. Here, we show that the matter above the critical point has a remarkable double universality not limited by pressure and temperature. The first universality is the transition between the liquidlike and gaslike states seen in the crossover of the specific heat on the dynamical length scale in deeply supercritical state and characterised by a fixed inversion point. The second universality is the operation of this effect in many supercritical fluids, including N$_2$, CO$_2$, Pb, H$_2$0 and Ar. Despite the differences in structure and chemical bonding in these fluids, the transition has the same fixed inversion point deep in the supercritical state. This provides new understanding of the supercritical state previously considered to be a featureless area on the phase diagram and a theoretical guide for improved and more efficient deployment of supercritical fluids in green and environmental applications.
Big and Nef Tautological Vector Bundles over the Hilbert Scheme of Points
Creators: name: Oprea, Dragos
Publisher: name: arXiv
Year: 2022
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: We study tautological vector bundles over the Hilbert scheme of points on surfaces. For each K-trivial surface, we write down a simple criterion ensuring that the tautological bundles are big and nef, and illustrate it by examples. In the K3 case, we extend recent constructions and results of Bini, Boissière and Flamini from the Hilbert scheme of 2 and 3 points to an arbitrary number of points. Among the K-trivial surfaces, the case of Enriques surfaces is the most involved. Our techniques apply to other smooth projective surfaces, including blowups of K3s and minimal surfaces of general type, as well as to the punctual Quot schemes of curves.
description: 21 pages