cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Analysis of ResearchGate, A Community Detection Approach
Creators: name: Heydari, Mohammad
name: Teimourpour, Babak
Publisher: name: arXiv
Year: 2020
Subjects: subject: Social and Information Networks (cs.SI)
subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: We are living in the data age. Communications over scientific networks creates new opportunities for researchers who aim to discover the hidden pattern in these huge repositories. This study utilizes network science to create collaboration network of Iranian Scientific Institutions. A modularity-based approach applied to find network communities. To reach a big picture of science production flow, analysis of the collaboration network is crucial. Our results demonstrated that geographic location closeness and ethnic attributes has important roles in academic collaboration network establishment. Besides, it shows that famous scientific centers in the capital city of Iran, Tehran has strong influence on the production flow of scientific activities. These academic papers are mostly viewed and downloaded from the United State of America, China, India, and Iran. The motivation of this research is that by discovering hidden communities in the network and finding the structure of intuitions communications, we can identify each scientific center research potential separately and clear mutual scientific fields. Therefore, an efficient strategic program can be designed, developed and tested to keep scientific centers in progress way and navigate their research goals into a straight useful roadmap to identify and fill the unknown gaps.
description: 5 pages, 6 Figures, International Conference of Web Research, ICWR, Tehran, 2020
Using math in physics -- 2. Estimation
Creators: name: Redish, Edward F.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Physics Education (physics.ed-ph)
subject: FOS: Physical sciences

description: Learning to use math in science is a non-trivial task. It involves many different skills (not usually taught in a math class) that help blend physical knowledge with mathematical symbology. One of these is the idea of quantification: that physical quantities can be assigned specific numbers. A second is to develop an intuition for scale. One way to help students develop these skills is to teach estimation: the ability to consider a physical situation and put reasonable approximate numbers to it
description: 5 pages, 2 figures
Using math in physics -- 4. Toy models
Creators: name: Redish, Edward F.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Physics Education (physics.ed-ph)
subject: FOS: Physical sciences

description: Learning to create, use, and evaluate models is a central element of becoming a scientist. In physics, we often begin an analysis of a complex system with highly simplified or toy models. In introductory physics classes, we tend to use them without comment or motivation. Some students infer that physics is irrelevant to their understanding of the real world and are discouraged from making the cognitive blend of physics concepts with math symbology essential for making sense of physics. In this paper, I discuss the often hidden barriers that make it difficult for our students to accept and understand the value of toy models, and suggest instructional approaches that can help.
description: 6 pages, 5 figures
Wave Propagation of Visual Stimuli in Focus of Attention
Creators: name: Faggi, Lapo
name: Betti, Alessandro
name: Zanca, Dario
name: Melacci, Stefano
name: Gori, Marco
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Artificial Intelligence (cs.AI)
subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: Fast reactions to changes in the surrounding visual environment require efficient attention mechanisms to reallocate computational resources to most relevant locations in the visual field. While current computational models keep improving their predictive ability thanks to the increasing availability of data, they still struggle approximating the effectiveness and efficiency exhibited by foveated animals. In this paper, we present a biologically-plausible computational model of focus of attention that exhibits spatiotemporal locality and that is very well-suited for parallel and distributed implementations. Attention emerges as a wave propagation process originated by visual stimuli corresponding to details and motion information. The resulting field obeys the principle of "inhibition of return" so as not to get stuck in potential holes. An accurate experimentation of the model shows that it achieves top level performance in scanpath prediction tasks. This can easily be understood at the light of a theoretical result that we establish in the paper, where we prove that as the velocity of wave propagation goes to infinity, the proposed model reduces to recently proposed state of the art gravitational models of focus of attention.
Using math in physics -- 3. Anchor equations
Creators: name: Redish, Edward F.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Physics Education (physics.ed-ph)
subject: FOS: Physical sciences

description: An important step in learning to use math in science is learning to see physics equations as not just calculational tools, but as ways of expressing fundamental relationships among physical quantities, of coding conceptual information, and of organizing physics knowledge structures. In this paper I discuss the role of basic anchor equations in introductory physics and show some examples of how to help students learn to use them.
description: 6 pages, 4 figures
An Improvement for Capsule Networks using Depthwise Separable Convolution
Creators: name: Phong, Nguyen Huu
name: Ribeiro, Bernardete
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Capsule Networks face a critical problem in computer vision in the sense that the image background can challenge its performance, although they learn very well on training data. In this work, we propose to improve Capsule Networks' architecture by replacing the Standard Convolution with a Depthwise Separable Convolution. This new design significantly reduces the model's total parameters while increases stability and offers competitive accuracy. In addition, the proposed model on $64\times64$ pixel images outperforms standard models on $32\times32$ and $64\times64$ pixel images. Moreover, we empirically evaluate these models with Deep Learning architectures using state-of-the-art Transfer Learning networks such as Inception V3 and MobileNet V1. The results show that Capsule Networks can perform comparably against Deep Learning models. To the best of our knowledge, we believe that this is the first work on the integration of Depthwise Separable Convolution into Capsule Networks.
description: 10 pages
Spectral distortion constraints on photon injection from low-mass decaying particles
Creators: name: Bolliet, Boris
name: Chluba, Jens
name: Battye, Richard
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Spectral distortions (SDs) of the cosmic microwave background (CMB) provide a powerful tool for studying particle physics. Here we compute the distortion signals from decaying particles that convert directly into photons at different epochs during cosmic history, focusing on injection energies $E_\mathrm{inj}\lesssim 20\,\mathrm{keV}$. We deliver a comprehensive library of SD solutions that can be used to study a wide range of particle physics scenarios. We use {\tt CosmoTherm} to compute the SD signals, including effects on the ionization history and opacities of the Universe. We also consider the effect of blackbody-induced stimulated decay, which can modify the injection history significantly. Then, we use data from COBE/FIRAS and EDGES to constrain the properties of the decaying particles. We explore scenarios where these provide a dark matter (DM) candidate or constitute only a small fraction of DM. We complement the SD constraints with CMB anisotropy constraints, highlighting new effects from injections at very-low photon energies ($hν\lesssim 10^{-4}\,\mathrm{eV}$). Our model-independent constraints exhibit rich structures in the lifetime-energy domain, covering injection energies $E_\mathrm{inj}\simeq 10^{-10}\mathrm{eV}-10\mathrm{keV}$ and lifetimes $τ_X\simeq 10^5\,\mathrm{s}-10^{33}\mathrm{s}$. We discuss the constraints on axions and axion-like particles that convert directly into two photons, revising existing SD constraints in the literature. Our limits are competitive with other constraints for axion masses $m_a c^2\gtrsim 27\,\mathrm{eV}$ and we find that simple estimates based on the overall energetics are generally inaccurate. Future CMB spectrometers could significantly improve the obtained constraints, thus providing an important complementary probe of early-universe particle physics.
description: match published version
Entwicklung und Evaluation der virtuellen Lern- und Arbeitsumgebung VILA
Creators: name: Zinn, Bernd
name: Guo, Qi
name: Sari, Duygu
Publisher: name: Journal of Technical Education (JOTED)
Year: 2016

description: Im Beitrag wird von der theoriegestützten Entwicklung und Evaluation der virtuellen Lern- und Arbeitsumgebung VILA berichtet. VILA wurde für die berufliche Aus- und WeiterÂ­bildung von Fachkräften im industriellen Dienstleistungsbereich entwickelt. Die Ergebnisse der mit (angehenden) Servicetechnikern in gewerblich-technischen Domänen (n = 62) und Berufs- und Technikpädagogen (n = 72) durchgeführte Evaluation lassen darauf schließen, dass die virtuelle Lern- und Arbeitsumgebung VILA mit ihren technologischen und funktionalen Optionen sowie ihrem methodisch-didaktischen Konzept zentrale AnforderunÂ­gen an ein situiertes und flexibles Lernen erfüllt und von den Befragten im Hinblick auf Usability, räumliche Präsenz und Flow-Erleben positiv wahrgenommen wird. In einem Strukturmodell zeigt sich, dass vor allem die wahrgenommene räumliche Präsenz das Flow-Erleben im virtuellen Setting determiniert. Schlüsselwörter: Virtuelles Lernen, Usability, räumliche Präsenz, Flow-Erleben, Evaluation
description: Journal of Technical Education (JOTED), Bd. 4 Nr. 1 (2016): Journal of Technical Education (JOTED)
Modeling and Forecasting Currency in Circulation in Ethiopia
Creators: name: Semate, Getahun
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2014

description: In the literature, Currency in circulation is typically estimated either by specifying a currency demand equation based on the theory of transaction and portfolio demand for money or univariate time series models. The first approach works well with low frequency data but faces limitations with high frequency data series. Using monthly and weekly data of currency in circulation form May 2007 to April 2014, the paper proposes an alternative approach in modeling the high frequency data series by using Multivariate time series (structural model and VAR) univariate time series(trend and ARIMA) Model. The four separate models were estimated with monthly, and two separate models with weekly time series, assembling tools for forecasting trend, seasonal patterns and cycles in individual series separately. Trend and seasonal effects were identified by regressing on trend and seasonal dummies while cyclical dynamics were captured by allowing for ARMA effect in the regression disturbances. The monthly and weekly models clearly identify both intra –month and inter-month variation of currency in circulation. The monthly trend model also indentified that Ethiopian New Year has significant positive impact on demand for currency in Ethiopia. Finally model comparison result showed both monthly VAR, and trend models outperforms the structural and ARIMA models and trend model performs the weekly data wheel at 5% level of significance. In general this methodology may be used in forecasting currency in circulation with careful assessment of month to month and week to week current developments in the economy.
Neutrino masses, vacuum stability and quantum gravity prediction for the mass of the top quark
Creators: name: Domènech, Guillem
name: Goodsell, Mark
name: Wetterich, Christof
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: A general prediction from asymptotically safe quantum gravity is the approximate vanishing of all quartic scalar couplings at the UV fixed point beyond the Planck scale. A vanishing Higgs doublet quartic coupling near the Planck scale translates into a prediction for the ratio between the mass of the Higgs boson $M_H$ and the top quark $M_t$. If only the standard model particles contribute to the running of couplings below the Planck mass, the observed $M_H\sim125\,{\rm GeV}$ results in the prediction for the top quark mass $M_t\sim 171\,{\rm GeV}$, in agreement with recent measurements. In this work, we study how the asymptotic safety prediction for the top quark mass is affected by possible physics at an intermediate scale. We investigate the effect of a $SU(2)$ triplet scalar and right-handed neutrinos, needed to explain the tiny mass of left-handed neutrinos. For pure seesaw II, with no or very heavy right handed neutrinos, the top mass can increase to $M_t\sim 172.5\,{\rm GeV}$ for a triplet mass of $M_Δ\sim 10^8{\rm GeV}$. Right handed neutrino masses at an intermediate scale increase the uncertainty of the predictions of $M_t$ due to unknown Yukawa couplings of the right-handed neutrinos and a cubic interaction in the scalar potential. For an appropriate range of Yukawa couplings there is no longer an issue of vacuum stability.
description: 18 pages, 16 figures. v2: Matches published version. We also corrected a typo in eq.(2.7)
Knowledge work in aircraft maintenance
Creators: name: Sobbe, Eileen
name: Tenberg, Ralf
name: Meyer, Hans
Publisher: name: Journal of Technical Education (JOTED)
Year: 2016

description: Knowledge work encompasses information processing and knowledge development tasks and places the knowledge worker at the centre of analysis. Knowledge and information are the knowledge worker's most precious resource in an increasingly complex working environment. Knowledge work is analysed in the context of the productive technical working environment of aircraft maintenance at Lufthansa Technik AG. The proportion of knowledge-intensive tasks in aircraft maintenance rises with increasing complexity of aircraft and their systems and components. The quantity of information and the resulting challenges for workers also increase accordingly. The findings generated by the study and a theoretical consideration of the subject are used to derive conclusions about the practice of aircraft maintenance and concrete recommendations for action. Keywords: Knowledge work, aircraft maintenance, knowledge, information, fields of action
description: Journal of Technical Education (JOTED), Bd. 4 Nr. 1 (2016): Journal of Technical Education (JOTED)
Weakly-Supervised Action Localization and Action Recognition using Global-Local Attention of 3D CNN
Creators: name: Yudistira, Novanto
name: Kavitha, Muthu Subash
name: Kurita, Takio
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Artificial Intelligence (cs.AI)
subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Computer and information sciences

description: 3D Convolutional Neural Network (3D CNN) captures spatial and temporal information on 3D data such as video sequences. However, due to the convolution and pooling mechanism, the information loss seems unavoidable. To improve the visual explanations and classification in 3D CNN, we propose two approaches; i) aggregate layer-wise global to local (global-local) discrete gradients using trained 3DResNext network, and ii) implement attention gating network to improve the accuracy of the action recognition. The proposed approach intends to show the usefulness of every layer termed as global-local attention in 3D CNN via visual attribution, weakly-supervised action localization, and action recognition. Firstly, the 3DResNext is trained and applied for action classification using backpropagation concerning the maximum predicted class. The gradients and activations of every layer are then up-sampled. Later, aggregation is used to produce more nuanced attention, which points out the most critical part of the predicted class's input videos. We use contour thresholding of final attention for final localization. We evaluate spatial and temporal action localization in trimmed videos using fine-grained visual explanation via 3DCam. Experimental results show that the proposed approach produces informative visual explanations and discriminative attention. Furthermore, the action recognition via attention gating on each layer produces better classification results than the baseline model.
'Locate' : a program for computer-aided workspace layout
Creators: name: Hendy, K. C.
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.
Limitations of empirical sediment transport formulas for shallow water and their consequences for swash zone modelling
Creators: name: Li, Wei
name: Hu, Peng
name: Pähtz, Thomas
name: He, Zhiguo
name: Cao, Zhixian
Publisher: name: arXiv
Year: 2016
Subjects: subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: Volumetric sediment concentrations computed by phase-resolving swash morphodynamic models are shown to exceed unity minus porosity (i.e. the maximal physically possible concentration value) by up to factor of $10^5$ when using standard expressions to compute the sediment transport rate. An ad hoc limit of sediment concentration is introduced as a means to evaluate consequences of exceeding physically realistic concentration by standard expressions. We find that implementation of this ad hoc limit strongly changes the quantitative and qualitative predictions of phase-resolving swash morphodynamic models, suggesting that existing swash predictions are unreliable. This is because standard expressions inappropriately consider or ignore the fact that the shallow swash water depth limits the storage capacity of transported sediment.
Practical Blind Membership Inference Attack via Differential Comparisons
Creators: name: Hui, Bo
name: Yang, Yuchen
name: Yuan, Haolin
name: Burlina, Philippe
name: Gong, Neil Zhenqiang
name: Cao, Yinzhi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cryptography and Security (cs.CR)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Membership inference (MI) attacks affect user privacy by inferring whether given data samples have been used to train a target learning model, e.g., a deep neural network. There are two types of MI attacks in the literature, i.e., these with and without shadow models. The success of the former heavily depends on the quality of the shadow model, i.e., the transferability between the shadow and the target; the latter, given only blackbox probing access to the target model, cannot make an effective inference of unknowns, compared with MI attacks using shadow models, due to the insufficient number of qualified samples labeled with ground truth membership information. In this paper, we propose an MI attack, called BlindMI, which probes the target model and extracts membership semantics via a novel approach, called differential comparison. The high-level idea is that BlindMI first generates a dataset with nonmembers via transforming existing samples into new samples, and then differentially moves samples from a target dataset to the generated, non-member set in an iterative manner. If the differential move of a sample increases the set distance, BlindMI considers the sample as non-member and vice versa. BlindMI was evaluated by comparing it with state-of-the-art MI attack algorithms. Our evaluation shows that BlindMI improves F1-score by nearly 20% when compared to state-of-the-art on some datasets, such as Purchase-50 and Birds-200, in the blind setting where the adversary does not know the target model's architecture and the target dataset's ground truth labels. We also show that BlindMI can defeat state-of-the-art defenses.
Symmetry breaking, slow relaxation dynamics, and topological defects at the field-induced helix reorientation in MnSi
Creators: name: Bauer, A.
name: Chacon, A.
name: Wagner, M.
name: Georgii, M. Halder. R.
name: Rosch, A.
name: Pfleiderer, C.
name: Garst, M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We report a study of the reorientation of the helimagnetic order in the archetypal cubic chiral magnet MnSi as a function of magnetic field direction. The reorientation process as inferred from small-angle neutron scattering, the magnetization, and the ac susceptibility is in excellent agreement with an effective mean-field theory taking into account the precise symmetries of the crystallographic space group. Depending on the field and temperature history and the direction of the field with respect to the crystalline axes, the helix reorientation may exhibit a crossover, a first-order, or a second-order transition. The magnetization and ac susceptibility provide evidence that the reorientation of helimagnetic domains is associated with large relaxation times exceeding seconds. At the second-order transitions residual Ising symmetries are spontaneously broken at continuous elastic instabilities of the helimagnetic order. In addition, on the time scales explored in our experiments these transitions are hysteretic as a function of field suggesting, within the same theoretical framework, the formation of an abundance of plastic deformations of the helical spin order. These deformations comprise topologically non-trivial disclinations, promising novel routes to spintronics applications alongside skyrmions discovered recently in the same class of materials.
description: 14 pages, 8 figures + Supplement (8 pages, 9 figures)
Betriebliches Kompetenzmanagement im Kontext des demografischen Wandels - Konzept und erste Befunde
Creators: name: Pittich, Daniel
name: Weber, Claudia
name: Stojanovic, Radica
Publisher: name: Journal of Technical Education (JOTED)
Year: 2016

description: Der vorliegende Beitrag geht auf ein BMBF-gefördertes Verbundprojekt zum Thema „Zielgerichtete, altersstrukturgerechte Vermittlung arbeitsplatzbezogener Kompetenzen durch Lernfabriken“ zurück. Im Projekt sollen neben Interventionen in unterschiedlich ausÂ­gerichteten Lernfabrik-Workshops auch betriebliche Kompetenzmanagementansätze (weiter-) entwickelt werden. Zu letztgenanntem Aspekt sollen nachfolgend neben AusgangsÂ­punkt und konzeptionellen Grundüberlegungen insbesondere erste empirische Zugänge und Befunde referiert werden. Der Fokus wird dabei auf einer Erhebung von Altersstereotypen und überfachlichen - insb. sozialen - Kompetenzen der MitarbeiterInnen sowie deren ZusammenÂ­hängen liegen. Abschließend soll skizziert werden, welche Implementierungen im Sinne des Kompetenzmanagements und welche weiteren wissenschaftliche Zugänge im Projektrahmen angestrebt werden. Schlüsselwörter: Altersstereotypen, Kompetenzentwicklung, Kompetenzmanagement, demoÂ­graphischer Wandel
description: Journal of Technical Education (JOTED), Bd. 4 Nr. 1 (2016): Journal of Technical Education (JOTED)
Aspects of a computer control of a thermofor catalytic cracking unit
Creators: name: Rye, D. .
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.
Förderung von Lernenden im technischen Unterricht an Werkreal- und Gemeinschaftsschulen
Creators: name: Wyrwal, Matthias
name: Zinn, Bernd
Publisher: name: Journal of Technical Education (JOTED)
Year: 2016

description: Der Übergang an der ersten Schwelle und der erfolgreiche Abschluss einer Ausbildung stellen sich für viele Jugendliche als problematisch dar. Insbesondere Schülerinnen und Schüler mit einem geringen schulischen Vorbildungsniveau haben oftmals große Probleme, die zunehmend komplexeren Anforderungen einer gewerblich-technischen Ausbildung zu erfüllen. Im Beitrag wird von der Entwicklung, Umsetzung und Erprobung des Berufsfeldspezifischen FörderÂ­trainings für Lernende im technischen Unterricht an Werkreal- und Gemeinschaftsschulen (BeFöLe) berichtet. Die Ergebnisse der Interventionsstudie, die innerhalb eines klassischen Experimentalkontrollgruppen-Design (n = 207) erhoben wurden, zeigen, dass durch das bereichsÂ­Â­spezifische StrategieÂ­training das technische Grundwissen und die wahrgenommene inhaltliche Relevanz der Lerninhalte signifikant gefördert werden können. Schlüsselwörter: Fördertraining, Berufsfeld, Werkreal- und Gemeinschaftsschulen, technisches Wissen, metakognitive Strategien, kognitive Strategien
description: Journal of Technical Education (JOTED), Bd. 4 Nr. 1 (2016): Journal of Technical Education (JOTED)
2-group global symmetries, hydrodynamics and holography
Creators: name: Iqbal, Nabil
name: Poovuttikul, Napat
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: 2-group global symmetries are a particular example of how higher-form and conventional global symmetries can fuse together into a larger structure. We construct a theory of hydrodynamics describing the finite-temperature realization of a 2-group global symmetry composed out of $U(1)$ zero-form and $U(1)$ one-form symmetries. We study aspects of the thermodynamics from a Euclidean partition function and derive constitutive relations for ideal hydrodynamics from various points of view. Novel features of the resulting theory include an analogue of the chiral magnetic effect and a chiral sound mode propagating along magnetic field lines. We also discuss a minimalist holographic description of a theory dual to 2-group global symmetry and verify predictions from hydrodynamic descriptions. Along the way we clarify some aspects of symmetry breaking in higher-form theories at finite temperature.
description: 32 pages + appendices, 6 figures
High-precision abundances of Sc, Mn, Cu, and Ba in solar twins. Trends of element ratios with stellar age
Creators: name: Nissen, P. E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: A previous study of correlations between element abundance ratios, [X/Fe], and ages of solar twin stars is extended to include Sc, Mn, Cu, and Ba. HARPS spectra with S/N > 600 are used to derive very precise (+/- 0.01 dex) differential abundances, and stellar ages with internal errors less than 1 Gyr are obtained by interpolation in the logg - Teff diagram between isochrones calculated with the Aarhus Stellar Evolution Code. For stars younger than 6 Gyr, [X/Fe] is tightly correlated with stellar age for all elements. For ages between 6 and 9 Gyr, the [X/Fe] - age correlations break down and the stars split up into two groups having respectively high and low [X/Fe] for the odd-Z elements. It is concluded that while stars in the solar neighborhood younger than about 6 Gyr were formed from interstellar gas with a smooth chemical evolution, older stars have originated from regions enriched by supernovae with different neutron excesses. Furthermore, the correlations between abundance ratios and stellar age suggest that: i) Sc is made in Type II supernovae along with the alpha-capture elements, ii) the Type II to Ia SNe yield ratio is about the same for Mn and Fe, iii) Cu is mainly made by the weak s-process in massive stars, iv) the Ba/Y yield ratio for AGB stars increases with decreasing stellar mass, v) [Y/Mg] and [Y/Al] can be used as "chemical clocks" when determining ages of solar metallicity stars.
description: 12 pages, 9 figures. Accepted for publication in A&A
Dissipative Kerr solitons in a photonic dimer on both sides of exceptional point
Creators: name: Komagata, Kenichi
name: Tikan, Alexey
name: Tusnin, Aleksandr
name: Riemensberger, Johann
name: Churaev, Mikhail
name: Guo, Hairun
name: Kippenberg, Tobias J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: Exceptional points are a ubiquitous concept widely present in driven-dissipative coupled systems described by a non-Hermitian Hamiltonian. It is characterized by the degeneracy of the Hamiltonian's eigenvalues and coalescence of corresponding eigenvectors. Recent developments demonstrated that exceptional points can play an important role in photonics. However, to date, exceptional points have been extensively examined in the systems supporting only a few optical modes, thereby leaving the observation of collective (multimode) effects outside of the scope of study. In the present paper, we analyze the role of exceptional points in nonlinear multimode photonics. Specifically, we provide insights into complex nonlinear dynamics arising in a continuous wave-driven pair of strongly coupled nonlinear micro-resonators (i.e. a nonlinear photonic dimer) operating in the multimode regime. Investigating this system, which is known to possess exceptional points, we find two fundamentally different nonlinear regimes of operation corresponding to effective parity-time symmetric and broken parity-time symmetry states. We demonstrate that the photonic dimer can be critically coupled to a bus waveguide, thereby, providing an efficient generation of the dissipative Kerr solitons on both sides of the exceptional point. The parity-time symmetric case, which corresponds to a pair of symmetrically split resonances, has been recently shown to exhibit a variety of emergent phenomena including gear soliton generation, symmetry breaking, and soliton hopping. Dissipative solitons generation in the parity-time symmetry broken case - leading to the dissipation splitting - up to now remains unexplored.
description: 19 pages, 10 figures
The Effects Of Shocks To Ethiopian Monetary Policy On Price And Output: SVAR Approach
Creators: name: Geremew, Anteneh
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2014

description: The Effects of Shocks to Ethiopian Monetary Policy on Price and Output: SVAR Approach Anteneh Geremew Addis Ababa University, June 2014 The main objective of this paper was to model and investigate the effect of shocks on Ethiopian monetary policy in to output and price using SVAR methodology. Using quarterly data 1995Q3 to 2011/12Q4, SVAR model is developed. Both the domestic (GDP, CPI, M0, T-bill rate) and foreign variables (OPI and WCPI) were used to investigate the Ethiopian monetary policy framework. I have imposed a contemporaneous restriction based on economic theory in order to provide some economic structure to Ethiopia SVAR. The results of innovation accounting analyses, generated from the SVAR model suggested that a positive shock to reserve money increased output significantly with a considerable lag spans one quarter, while price respond to a positive shock to reserve money negatively for a period of one and half and after this period it was increased and sustained for long periods. A notable difference with the monetary policy variables (reserve money and T-bill rate) shock effect on output and price were obtained. I obtained that the variability of price and output due to shock to reserve money was more explained than T-bill rate shock in the short term as well as the long term horizons. Finally, based on the findings I have drawn my recommendations. The finding indicated that in the short term and long term variability of price and output were more explained due to shock to reserve money than T-bill rate shock, therefore, the NBE should be ensure that reserve money and interest policy are consistent with each other and further studies should be needed to identified different monetary transmission mechanisms or cannels in Ethiopia
Differential Privacy-Based Online Allocations towards Integrating Blockchain and Edge Computing
Creators: name: Guo, Jianxiong
name: Wu, Weili
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cryptography and Security (cs.CR)
subject: Computer Science and Game Theory (cs.GT)
subject: FOS: Computer and information sciences

description: In recent years, the blockchain-based Internet of Things (IoT) has been researched and applied widely, where each IoT device can act as a node in the blockchain. However, these lightweight nodes usually do not have enough computing power to complete the consensus or other computing-required tasks. Edge computing network gives a platform to provide computing power to IoT devices. A fundamental problem is how to allocate limited edge servers to IoT devices in a highly untrustworthy environment. In a fair competition environment, the allocation mechanism should be online, truthful, and privacy safe. To address these three challenges, we propose an online multi-item double auction (MIDA) mechanism, where IoT devices are buyers and edge servers are sellers. In order to achieve the truthfulness, the participants' private information is at risk of being exposed by inference attack, which may lead to malicious manipulation of the market by adversaries. Then, we improve our MIDA mechanism based on differential privacy to protect sensitive information from being leaked. It interferes with the auction results slightly but guarantees privacy protection with high confidence. Besides, we upgrade our privacy-preserving MIDA mechanism such that adapting to more complex and realistic scenarios. In the end, the effectiveness and correctness of algorithms are evaluated and verified by theoretical analysis and numerical simulations.
4D Dual-Tree Complex Wavelets for Time-Dependent Data
Creators: name: Bubba, Tatiana A.
name: Heikkilä, Tommi
name: Siltanen, Samuli
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: Image and Video Processing (eess.IV)
subject: FOS: Mathematics
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: The dual-tree complex wavelet transform (DT-$\mathbb{C}$WT) is extended to the 4D setting. Key properties of 4D DT-$\mathbb{C}$WT, such as directional sensitivity and shift-invariance, are discussed and illustrated in a tomographic application. The inverse problem of reconstructing a dynamic three-dimensional target from X-ray projection measurements can be formulated as 4D space-time tomography. The results suggest that 4D DT-$\mathbb{C}$WT offers simple implementations combined with useful theoretical properties for tomographic reconstruction.
A brief review of measurements of electroweak bosons at the LHCb experiment in LHC Run 1
Creators: name: Barter, W.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The LHCb experiment is one of four major experiments at the LHC. Despite being designed for the study of beauty and charm particles, it has made important contributions in other areas, such as the production and decay of $W$ and $Z$ bosons. Such measurements can be used to study and constrain parton distribution functions, as well as to test perturbative quantum chromodynamics in hard scattering processes. The angular structure of $Z$ boson decays to leptons can also be studied and used to measure the weak mixing angle. The phase space probed by LHCb is particularly sensitive to this quantity, and the LHCb measurement using the dimuon final state is currently the most precise determination of $\sin^2θ^\text{lept.}_\text{eff.}$ at the LHC. LHCb measurements made using data collected during the first period of LHC operations (LHC Run 1) are discussed in this review. The article also considers the potential impact of related future measurements.
description: 18 pages, 8 figures, invited review submitted for publication in Modern Physics Letters A
The Fiscal Effects Of Foreign Aid In Ethiopia
Creators: name: Seid, Amir
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2014

description: This study tries to examine the effects of aid inflows on the government fiscal behavior, such as, taxation, borrowing and the allocation of other expenditure in Ethiopia by using a time series data from the period 1960-2012. There are five models, these models analyzed by applying the VECM and impulse response analysis. The results of the models indicate that an increase in grant results in an increase in the total tax revenue and total expenditure. But the disaggregation of tax revenue gives a different result on tax collection effort. The flow of grant has a tendency to decline direct tax collection effort. And also grant has a decrease effect on domestic borrowing, whereas the flow of grant encourages the government to increase both capital and recurrent expenditure. However, in relation to loan the result shows that loan has no effect on the fiscal components. Moreover, a model that includes ODA instead of either one of the two external financing components is estimated. The reason of incorporating ODA is that aid disbursed outside the budgetary framework can also affect government spending decisions. The results of an increase in ODA are similar to those of an increase in grants. Direct taxes and domestic borrowing fall, whereas recurrent expenditure rises. In addition, in the long run both capital expenditure and indirect tax affected by the flow of ODA in small amount. This might show ODA is more pro-consumption than investment and also aid and domestic borrowing are close substitutes.
Perfect points of abelian varieties
Creators: name: Ambrosi, Emiliano
Publisher: name: arXiv
Year: 2021
Subjects: subject: Number Theory (math.NT)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: Let $k$ be an algebraic extension of $\mathbb F_p$ and $K/k$ a regular extension of fields (e.g. $\mathbb F_p(T)/\mathbb F_p$). Let $A$ be a $K$-abelian variety such that all the isogeny factors are neither isotrivial nor of $p$-rank zero. We give a necessary and sufficient condition for the finite generation of $A(K^{perf})$ in terms of the action of $End(A)\otimes \mathbb Q_p$ on the $p$-divisible group $A[p^{\infty}]$ of $A$. In particular we prove that if $End(A)\otimes \mathbb Q_p$ is a division algebra then $A(K^{perf})$ is finitely generated. This implies the "full" Mordell-Lang conjecture for these abelian varieties. In addition we prove that all the infinitely $p$-divisible elements in $A(K^{perf})$ are torsion. These reprove and extend previous results to the non ordinary case. One of the main technical intermediate result is an overconvergence theorem for the Dieudonné module of certain semiabelian schemes over smooth varieties.
description: v3: 16 pages, shortened and final version. To appear in Compositio Mathematica. Some of the results in Part II will appear elsewhere. v2: minor edits. v1:37 pages, comments are very welcome
Optimizing the Stability of FETs Based on Two-Dimensional Materials by Fermi Level Tuning
Creators: name: Knobloch, Theresia
name: Uzlu, Burkay
name: Illarionov, Yury Yu.
name: Wang, Zhenxing
name: Otto, Martin
name: Filipovic, Lado
name: Waltl, Michael
name: Neumaier, Daniel
name: Lemme, Max C.
name: Grasser, Tibor
Publisher: name: arXiv
Year: 2021
Subjects: subject: Applied Physics (physics.app-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Despite the enormous progress achieved during the past decade, nanoelectronic devices based on two-dimensional (2D) semiconductors still suffer from a limited electrical stability. This limited stability has been shown to result from the interaction of charge carriers originating from the 2D semiconductors with defects in the surrounding insulating materials. The resulting dynamically trapped charges are particularly relevant in field effect transistors (FETs) and can lead to a large hysteresis, which endangers stable circuit operation. Based on the notion that charge trapping is highly sensitive to the energetic alignment of the channel Fermi-level with the defect band in the insulator, we propose to optimize device stability by deliberately tuning the channel Fermi-level. Our approach aims to minimize the amount of electrically active border traps without modifying the total number of traps in the insulator. We demonstrate the applicability of this idea by using two differently doped graphene layers in otherwise identical FETs with Al$_2$O$_3$ as a gate oxide mounted on a flexible substrate. Our results clearly show that by increasing the distance of the Fermi-level to the defect band, the hysteresis is significantly reduced. Furthermore, since long-term reliability is also very sensitive to trapped charges, a corresponding improvement in reliability is both expected theoretically and demonstrated experimentally. Our study paves the way for the construction of more stable and reliable 2D FETs in which the channel material is carefully chosen and tuned to maximize the energetic distance between charge carriers in the channel and the defect bands in the insulator employed.
description: 28 pages, 6 figures
The Impact of Public Final Consumption and Investment Spending on Economic Growth in Ethiopia: An Application of Vector Error Correction Model
Creators: name: Abdulaziz, Adnan
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2014

description: The objective of this paper was to investigate the impact of public sector investment and final consumption expenditure on economic growth using time series data on Ethiopia (for 54 years). In addition, it intended to explore the pattern and relative impact of public and private consumption and investment decision on the economy. I formulate a simple growth accounting model, adapting Ram (1986) in which total government expenditure is disaggregated into expenditure on (physical) investment and final consumption. The analysis is based on time series data covering the period 1960-2014. The study applies the augmented Dickey Fuller test for stationarity and Johansson co-integration test used to determine whether there is a long run relationship between variables. Vector error correction model is applied to estimate both short and long run models related with Real Gross Domestic Product of Ethiopia. The empirical results suggest that in the long run government investments and final consumption has positive and negative effect on economic growth, respectively. Similarly, private investment, private final consumption and primary education enrolment rate have positive effects on economic growth. However, all variables included in the model except government consumption do not have an impact on economic growth in the short run
Is the newly reported $X(5568)$ a $B\bar{K}$ molecular state?
Creators: name: Chen, Rui
name: Liu, Xiang
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In this work, we perform a dynamical study of the $B^{(*)}$ and $\bar K$ interaction and show that the newly reported $X(5568)$ or $X(5616)$ cannot be assigned to be an isovector $B\bar{K}$ or $B^*\bar{K}$ molecular state. We continue to investigate the isoscalar $B^{(*)}\bar{K}$ systems, and the $B^{(*)}\bar{K}$ systems with isospin $I=0,1$, and predict the existence of several isoscalar $B^{(*)}\bar K^{(*)}$ molecular states. A new task of exploring open-bottom molecular states will be created for future experiments.
description: 6 pages, 3 tables and 1 figure. Version accepted for publication in Phys. Rev. D
Wie kommt die Technik in die Schule?
Creators: name: Tenberg, Ralf
Publisher: name: Journal of Technical Education (JOTED)
Year: 2016

description: „Wie kommt die Technik in die Schule“ fragen sich zunehmend jene Teile unseres BildungsÂ­systems, die technische Kompetenzen vermitteln, also Berufsschulen, Betriebe und technische Hochschulen. Nicht erst im Zuge des demografischen Wandels sehen sich vor allem die technikorientierten Bereiche der postschulischen Bildung mit quantitativen aber auch qualiÂ­tativen Nachwuchs-Problemen konfrontiert. Immer weniger junge Menschen wählen einen technischen Bildungsweg und zudem werden die technischen Basiskompetenzen der nachÂ­folgenden Generationen immer geringer. Um einen Ausbilder eines Großbetriebs zu zitieren: „von den Auszubildenden, die wir dieses Jahr für den Beruf des Industriemechanikers einstellen, kann nicht einmal die Hälfte eine einfache Reparatur an ihrem Fahrrad durchÂ­führen“...
description: Journal of Technical Education (JOTED), Bd. 4 Nr. 1 (2016): Journal of Technical Education (JOTED)
Dual bus intelligent disk controller hardware design
Creators: name: Malekzadeh., Mohammad Ali
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.
The Economy - Wide Impact of Continental Free Trade Area (CFTA) On Ethiopia: A Recursive Dynamic Computable General Equilibrium Approach
Creators: name: Hailemeskel, Begidu
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2016

description: This study examines the economy wide impact of CFTA on Ethiopia. The analysis is made based on Ethiopian social accounting matrix (SAM) of 2009/10 constructed by EDRI. The study has utilized a recursive dynamic CGE model. The model is simulated for an import tariff reduction on different sectors using three different scenarios. The scenarios involve joining CFTA at one time, in 2016, or through phases, a 25% tariff removal each year from 2016-2019. Another scenario involves excluding strategic sectors from the CFTA. The impact of CFTA result shows, Government revenue also decreases as tariff revenue is an important source of revenue for the Ethiopian government. GDP and trade balance are, however, positively affected. The increase in GDP might be associated to the increase in disaggregated production. The larger increase in exports as compared to the increase in imports leads to an improvement in trade balance. Household consumption expenditure also increases. This might be due to the availability of cheap consumption commodities from abroad due to the removal of tariff. On the other hand, our results show a decrease in investment which might be attributed to the inability of domestic producers to compete with foreign suppliers at a lower price. Our findings also show that protection of strategic sectors benefits only producers in these sectors. Exclusion of strategic sectors from CFTA helps producers face less competition as the price of imported commodities will include tariffs. Protection of strategic sectors will also increase government revenue. The impact of protecting strategic sectors on the overall economy, however, is negative, which is it results in a decrease in GDP.