cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
IBIR: Bug Report driven Fault Injection
Creators: name: Khanfir, Ahmed
name: Koyuncu, Anil
name: Papadakis, Mike
name: Cordy, Maxime
name: Bissyandé, Tegawendé F.
name: Klein, Jacques
name: Traon, Yves Le
Publisher: name: arXiv
Year: 2020
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: Much research on software engineering and software testing relies on experimental studies based on fault injection. Fault injection, however, is not often relevant to emulate real-world software faults since it "blindly" injects large numbers of faults. It remains indeed challenging to inject few but realistic faults that target a particular functionality in a program. In this work, we introduce IBIR, a fault injection tool that addresses this challenge by exploring change patterns associated to user-reported faults. To inject realistic faults, we create mutants by retargeting a bug report driven automated program repair system, i.e., reversing its code transformation templates. IBIR is further appealing in practice since it requires deep knowledge of neither of the code nor the tests, but just of the program's relevant bug reports. Thus, our approach focuses the fault injection on the feature targeted by the bug report. We assess IBIR by considering the Defects4J dataset. Experimental results show that our approach outperforms the fault injection performed by traditional mutation testing in terms of semantic similarity with the original bug, when applied at either system or class levels of granularity, and provides better, statistically significant, estimations of test effectiveness (fault detection). Additionally, when injecting 100 faults, IBIR injects faults that couple with the real ones in 36% of the cases, while mutants from mutation testing inject less than 1%. Overall, IBIR targets real functionality and injects realistic and diverse faults.
Scientific evidence of CDK4/6 inhibitors in HR+/HER2- advanced/metastatic breast cancer: A scoping review
Creators: name: Odds
Publisher: name: Open Science Framework
Year: 2023
Subjects: subject: Medicine and Health Sciences

description: Conduct a scoping review of the scientific evidence regarding the use of CDK4/6 inhibitors (palbociclib, ribociclib, and abemaciclib) in patients over 18 years old with HR+/HER2- metastatic breast cancer (a/mBC) in terms of progression-free survival (PFS), overall survival (OS), and quality of life (QoL).
Antiferro-quadrupolar correlations in the quantum spin ice candidate Pr2Zr2O7
Creators: name: Petit, S.
name: Lhotel, E.
name: Florea, S. Guitteny O.
name: Robert, J.
name: Bonville, P.
name: Mirebeau, I.
name: Ollivier, J.
name: Mutka, H.
name: Ressouche, E.
name: Decorse, C.
name: Hatnean, M. Ciomaga
name: Balakrishnan, G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present an experimental study of the quantum spin ice candidate pyrochlore coumpound \przr\ by means of magnetization measurements, specific heat and neutron scattering up to 12 T and down to 60 mK. When the field is applied along the $[111]$ and $[1\bar{1}0]$ directions, ${\bf k}=0$ field induced structures settle in. We find that the ordered moment rises slowly, even at very low temperature, in agreement with macroscopic magnetization. Interestingly, for $H \parallel [1\bar{1}0]$, the ordered moment appears on the so called $α$ chains only. The spin excitation spectrum is essentially {\it inelastic} and consists in a broad flat mode centered at about 0.4 meV with a magnetic structure factor which resembles the spin ice pattern. For $H \parallel [1\bar{1}0]$ (at least up to 2.5 T), we find that a well defined mode forms from this broad response, whose energy increases with $H$, in the same way as the temperature of the specific heat anomaly. We finally discuss these results in the light of mean field calculations and propose a new interpretation where quadrupolar interactions play a major role, overcoming the magnetic exchange. In this picture, the spin ice pattern appears shifted up to finite energy because of those new interactions. We then propose a range of acceptable parameters for \przr\, that allow to reproduce several experimental features observed under field. With these parameters, the actual ground state of this material would be an antiferroquadrupolar liquid with spin-ice like excitations.
Transiting exoplanet candidates from K2 Campaigns 5 and 6
Creators: name: Pope, Benjamin J. S.
name: Parviainen, Hannu
name: Aigrain, Suzanne
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We introduce a new transit search and vetting pipeline for observations from the K2 mission, and present the candidate transiting planets identified by this pipeline out of the targets in Campaigns 5 and 6. Our pipeline uses the Gaussian Process-based K2SC code to correct for the K2 pointing systematics and simultaneously model stellar variability. The systematics-corrected, variability-detrended light curves are searched for transits with the Box Least Squares method, and a period-dependent detection threshold is used to generate a preliminary candidate list. Two or three individuals vet each candidate manually to produce the final candidate list, using a set of automatically-generated transit fits and assorted diagnostic tests to inform the vetting. We detect 147 single-planet system candidates and 5 multi-planet systems, independently recovering the previously-published hot~Jupiters EPIC 212110888b, WASP-55b (EPIC 212300977b) and Qatar-2b (EPIC 212756297b). We also report the outcome of reconnaissance spectroscopy carried out for all candidates with Kepler magnitude Kp < 13, identifying 12 targets as likely false positives. We compare our results to those of other K2 transit search pipelines, noting that ours performs particularly well for variable and/or active stars, but that the results are very similar overall. All the light curves and code used in the transit search and vetting process are publicly available, as are the follow-up spectra.
description: Accepted to MNRAS
Tracking fast and slow changes in synaptic weights from simultaneously observed pre- and postsynaptic spiking
Creators: name: Wei, Ganchao
name: Stevenson, Ian H.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: Applications (stat.AP)
subject: Computation (stat.CO)
subject: FOS: Biological sciences
subject: FOS: Computer and information sciences

description: Synapses change on multiple timescales, ranging from milliseconds to minutes, due to a combination of both short- and long-term plasticity. Here we develop an extension of the common Generalized Linear Model to infer both short- and long-term changes in the coupling between a pre- and post-synaptic neuron based on observed spiking activity. We model short-term synaptic plasticity using additive effects that depend on the presynaptic spike timing, and we model long-term changes in both synaptic weight and baseline firing rate using point process adaptive smoothing. Using simulations, we first show that this model can accurately recover time-varying synaptic weights 1) for both depressing and facilitating synapses, 2) with a variety of long-term changes (including realistic changes, such as due to STDP), 3) with a range of pre- and post-synaptic firing rates, and 4) for both excitatory and inhibitory synapses. We then apply our model to two experimentally recorded putative synaptic connections. We find that simultaneously tracking fast changes in synaptic weights, slow changes in synaptic weights, and unexplained variations in baseline firing is essential. Omitting any one of these factors can lead to spurious inferences for the others. Altogether, this model provides a flexible framework for tracking short- and long-term variation in spike transmission.
MPEC 2023-R196 : 2023 RY8
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 RY8

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Global analysis of VHHs framework regions with a structural alphabet
Creators: name: Noël, Floriane
name: Malpertuy, Alain
name: De Brevern, Alexandre
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantitative Methods (q-bio.QM)
subject: Biomolecules (q-bio.BM)
subject: FOS: Biological sciences

description: The VHHs are antigen-binding region/domain of camelid heavy chain antibodies (HCAb). They have many interesting biotechnological and biomedical properties due to their small size, high solubility and stability, and high affinity and specificity for their antigens. HCAb and classical IgGs are evolutionary related and share a common fold. VHHs are composed of regions considered as constant, called the frameworks (FRs) connected by Complementarity Determining Regions (CDRs), a highly variable region that provide interaction with the epitope. Actually, no systematic structural analyses had been performed on VHH structures despite a significant number of structures. This work is the first study to analyse the structural diversity of FRs of VHHs. Using a structural alphabet that allows approximating the local conformation, we show that each of the four FRs do not have a unique structure but exhibit many structural variant patterns. Moreover, no direct simple link between the local conformational change and amino acid composition can be detected. These results indicate that long-range interactions affect the local conformation of FRs and impact the building of structural models.
Domain Generalization: A Survey
Creators: name: Zhou, Kaiyang
name: Liu, Ziwei
name: Qiao, Yu
name: Xiang, Tao
name: Loy, Chen Change
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Generalization to out-of-distribution (OOD) data is a capability natural to humans yet challenging for machines to reproduce. This is because most learning algorithms strongly rely on the i.i.d.~assumption on source/target data, which is often violated in practice due to domain shift. Domain generalization (DG) aims to achieve OOD generalization by using only source data for model learning. Over the last ten years, research in DG has made great progress, leading to a broad spectrum of methodologies, e.g., those based on domain alignment, meta-learning, data augmentation, or ensemble learning, to name a few; DG has also been studied in various application areas including computer vision, speech recognition, natural language processing, medical imaging, and reinforcement learning. In this paper, for the first time a comprehensive literature review in DG is provided to summarize the developments over the past decade. Specifically, we first cover the background by formally defining DG and relating it to other relevant fields like domain adaptation and transfer learning. Then, we conduct a thorough review into existing methods and theories. Finally, we conclude this survey with insights and discussions on future research directions.
description: IEEE Transactions on Pattern Analysis and Machine Intelligence (TPAMI), 2022
Cool Subdwarf Investigations III: Dynamical Masses of Low Metallicity Subdwarfs
Creators: name: Jao, Wei-Chun
name: Nelan, Ed
name: Henry, Todd
name: Franz, Otto
name: Wasserman, Lawrence
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We report dynamical mass measurements for the components of the previously known double-lined spectroscopic subdwarfs G 006-026 B and C using the Fine Guidance Sensors (FGS) on the Hubble Space Telescope. To build the empirical mass-luminosity relation for low metallicity subdwarfs, we collect four other subdwarf systems with dynamical masses that we compare to theoretical models for various metallicities on the mass-luminosity relation. For most stars, they fall in the regions where the models predict to be low metallicity. This effort highlights the scarcity of dynamical masses for subdwarfs and that much work remains to be done to improve the mass errors and metallicity measurements of low mass subdwarfs in our Galaxy.
description: accepted for publication in Astronomical Journal
Sensing solvents with ultra-sensitive porous poly(ionic liquid) actuators
Creators: name: Zhao, Qiang
name: Heyda, Jan
name: Dzubiella, Joachim
name: Täuber, Karoline
name: Dunlop, John W. C.
name: Yuan, Jiayin
Publisher: name: arXiv
Year: 2016
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We introduced a new concept for fabricating solvent stimulus polymer actuators with unprecedented sensitivity and accuracy. This was accomplished by integrating porous architectures and electrostatic complexation gradients in a poly(ionic liquid) membrane that bears ionic liquid species for solvent sorption. In contact with 1.5 mol% of acetone molecules in water, the actuator membrane (1 mm x 20 mm x 30 um) bent into a closed loop. While the interaction between solvents and the polymer drives the actuation, the continuous gradient in complexation degree combined with the porous architecture optimizes the actuation, giving it a high sensitivity and even the ability to discriminate butanol solvent isomers. The membrane is also capable of cooperative actuation. The design concept is easy to implement and applicable to other polyelectrolyte systems, which substantially underpins their potentials in smart and sensitive signaling microrobotics/devices.
description: 32 page, 23 figures
Autonomous Flight in Unknown GNSS-denied Environments for Disaster Examination
Creators: name: Schleich, Daniel
name: Beul, Marius
name: Quenzel, Jan
name: Behnke, Sven
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Micro aerial vehicles (MAVs) have high potential for information gathering tasks to support situation awareness in search and rescue scenarios. Manually controlling MAVs in such scenarios requires experienced pilots and is error-prone, especially in stressful situations of real emergencies. The conditions of disaster scenarios are also challenging for autonomous MAV systems. The environment is usually not known in advance and GNSS might not always be available. We present a system for autonomous MAV flights in unknown environments which does not rely on global positioning systems. The method is evaluated in multiple search and rescue scenarios and allows for safe autonomous flights, even when transitioning between indoor and outdoor areas.
Competing spreading processes and immunization in multiplex networks
Creators: name: Gao, Bo
name: Zhao, Dawei
Publisher: name: arXiv
Year: 2016
Subjects: subject: Social and Information Networks (cs.SI)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Epidemic spreading on physical contact network will naturally introduce the human awareness information diffusion on virtual contact network, and the awareness diffusion will in turn depress the epidemic spreading, thus forming the competing spreading processes of epidemic and awareness in a multiplex networks. In this paper, we study the competing dynamics of epidemic and awareness, both of which follow the SIR process, in a two-layer networks based on microscopic Markov chain approach and numerical simulations. We find that strong capacities of awareness diffusion and self-protection of individuals could lead to a much higher epidemic threshold and a smaller outbreak size. However, the self-awareness of individuals has no obvious effect on the epidemic threshold and outbreak size. In addition, the immunization of the physical contact network under the interplay between of epidemic and awareness spreading is also investigated. The targeted immunization is found performs much better than random immunization, and the awareness diffusion could reduce the immunization threshold for both type of random and targeted immunization significantly.
Learning Optimal Parameters for Multi-target Tracking with Contextual Interactions
Creators: name: Wang, Shaofei
name: Fowlkes, Charless C.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: We describe an end-to-end framework for learning parameters of min-cost flow multi-target tracking problem with quadratic trajectory interactions including suppression of overlapping tracks and contextual cues about cooccurrence of different objects. Our approach utilizes structured prediction with a tracking-specific loss function to learn the complete set of model parameters. In this learning framework, we evaluate two different approaches to finding an optimal set of tracks under a quadratic model objective, one based on an LP relaxation and the other based on novel greedy variants of dynamic programming that handle pairwise interactions. We find the greedy algorithms achieve almost equivalent accuracy to the LP relaxation while being up to 10x faster than a commercial LP solver. We evaluate trained models on three challenging benchmarks. Surprisingly, we find that with proper parameter learning, our simple data association model without explicit appearance/motion reasoning is able to achieve comparable or better accuracy than many state-of-the-art methods that use far more complex motion features or appearance affinity metric learning.
description: arXiv admin note: text overlap with arXiv:1412.2066
Fairness in Ranking: A Survey
Creators: name: Zehlike, Meike
name: Yang, Ke
name: Stoyanovich, Julia
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Retrieval (cs.IR)
subject: Databases (cs.DB)
subject: FOS: Computer and information sciences
subject: I.2.6; I.2.8; H.3.3

description: In the past few years, there has been much work on incorporating fairness requirements into algorithmic rankers, with contributions coming from the data management, algorithms, information retrieval, and recommender systems communities. In this survey we give a systematic overview of this work, offering a broad perspective that connects formalizations and algorithmic approaches across subfields. An important contribution of our work is in developing a common narrative around the value frameworks that motivate specific fairness-enhancing interventions in ranking. This allows us to unify the presentation of mitigation objectives and of algorithmic techniques to help meet those objectives or identify trade-offs. In this survey, we describe four classification frameworks for fairness-enhancing interventions, along which we relate the technical methods surveyed in this paper, discuss evaluation datasets, and present technical work on fairness in score-based ranking. Then, we present methods that incorporate fairness in supervised learning, and also give representative examples of recent work on fairness in recommendation and matchmaking systems. We also discuss evaluation frameworks for fair score-based ranking and fair learning-to-rank, and draw a set of recommendations for the evaluation of fair ranking methods.
description: 72 pages. ACM CSUR (2022)
Localization due to interaction-enhanced disorder in bosonic systems
Creators: name: Singh, Rajeev
name: Shimshoni, Efrat
Publisher: name: arXiv
Year: 2016
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Localization in interacting systems caused by disorder, known as many-body localization (MBL), has attracted a lot of attention in recent years. Most systems studied in this context also show single-particle localization, and the question of MBL is whether the phenomena survives the effects of interactions. It is intriguing to consider a system with no single-particle localization but which does localize in the presence of many particles. The localization phenomena occurs "due to" rather than "in spite of" interactions in such systems. We consider a simple bosonic system and show that interactions enhance the effects of very weak disorder and result in localization when many particles are present. We provide physical insights into the mechanism involved and support our results with analytical and numerical calculations.
description: 8 pages, 4 figures
Revealing the Hidden Structural Phases of FeRh
Creators: name: Kim, Jinwoong
name: Ramesh, R.
name: Kioussis, Nicholas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: ${\it Ab}$ ${\it initio}$ electronic structure calculations reveal that tetragonal distortion has a dramatic effect on the relative stability of the various magnetic structures (C-, A-, G-, A$'$-AFM, and FM) of FeRh giving rise to a wide range of novel stable/metastable structures and magnetic phase transitions between these states. We predict that the ${\it cubic}$ G-AFM structure, which was believed thus far to be the ground state, is metastable and that the ${\it tetragonally}$ expanded G-AFM is the stable structure. The low energy barrier separating these states suggests phase coexistence at room temperature. We propose a novel A$'$-AFM phase to be the ${\it global}$ ground state among all magnetic phases which arises from the strain-induced tuning of the exchange interactions. The results elucidate the underlying mechanism for the recent experimental findings of electric-field control of magnetic phase transition driven via tetragonal strain. The novel magnetic phase transitions open interesting prospects for exploiting strain engineering for the next-generation memory devices.
Imperfect synchronized states and chimera states in two interacting populations of nonlocally coupled Stuart-Landau oscillators
Creators: name: Premalatha, K.
name: Chandrasekar, V. K.
name: Senthilvelan, M.
name: Lakshmanan, M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: We investigate the emergence of different kinds of imperfect synchronized states and chimera states in two interacting populations of nonlocally coupled Stuart-Landau oscillators. We find that the complete synchronization in population-I and existence of solitary oscillators which escape from the synchronized group in population-II lead to imperfect synchronized states for sufficiently small values of nonisochronicity parameter. Interestingly, on increasing the strength of this parameter further there occurs an onset of mixed imperfect synchronized states where the solitary oscillators occur from both the populations. Synchronized oscillators from both the populations are locked to a common average frequency. In both the cases of imperfect synchronized states synchronized oscillators exhibit periodic motion while the solitary oscillators are quasi-periodic in nature. In this region, for spatially prepared initial conditions, we can observe the mixed chimera states where the coexistence of synchronized and desynchronized oscillations occur from both the populations. On the other hand, imperfect synchronized states are not always stable, and they can drift aperiodically due to instability caused by an increase of nonisochronicity parameter. We observe that these states are robust to the introduction of frequency mismatch between the two populations.
description: Accepted for publication in Phys. Rev. E
QECOOL: On-Line Quantum Error Correction with a Superconducting Decoder for Surface Code
Creators: name: Ueno, Yosuke
name: Kondo, Masaaki
name: Tanaka, Masamitsu
name: Suzuki, Yasunari
name: Tabuchi, Yutaka
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Due to the low error tolerance of a qubit, detecting and correcting errors on it is essential for fault-tolerant quantum computing. Surface code (SC) associated with its decoding algorithm is one of the most promising quantum error correction (QEC) methods. % One of the challenges of QEC is its high complexity and computational demand. QEC needs to be very power-efficient since the power budget is limited inside of a dilution refrigerator for superconducting qubits by which one of the most successful quantum computers (QCs) is built. In this paper, we propose an online-QEC algorithm and its hardware implementation with SFQ-based superconducting digital circuits. We design a key building block of the proposed hardware with an SFQ cell library and evaluate it by the SPICE-level simulation. Each logic element is composed of about 3000 Josephson junctions and power consumption is about 2.78 uW when operating with 2 GHz clock frequency which meets the required decoding speed. Our decoder is simulated on a quantum error simulator for code distances 5 to 13 and achieves a 1.0% accuracy threshold.
description: 6 pages, 7 figures. This paper will be published in Proc. IEEE/ACM Design Automation Conference (DAC) 2021
Obscured AGNs in Bulgeless Hosts discovered by WISE: The Case Study of SDSS J1224+5555
Creators: name: Satyapal, S.
name: Secrest, N. J.
name: Rothberg, B.
name: O'Connor, J.
name: Ellison, S. L.
name: Hickox, R. C.
name: Constantin, A.
name: Gliozzi, M.
name: Rosenberg, J. L.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: There is mounting evidence that supermassive black holes form and grow in bulgeless galaxies. However, a robust determination of the fraction of AGNs in bulgeless galaxies, an important constraint to models of supermassive black hole seed formation and merger-free models of AGN fueling, is unknown, since optical studies have been shown to be incomplete for low mass AGNs. In a recent study using the Wide-field Infrared Survey Explorer, we discovered hundreds of bulgeless galaxies that display mid-infrared signatures of extremely hot dust suggestive of powerful accreting massive black holes, despite having no signatures of black hole activity at optical wavelengths. Here we report X-ray follow-up observations of J122434.66+555522.3, a nearby (z=0.052) isolated bulgeless galaxy that contains an unresolved X-ray source detected at the 3 sigma level by XMM-Newton with an observed luminosity uncorrected for intrinsic absorption of L{2-10~keV}=1.1+/-0.4 10^40 ergs/s. Ground-based near-infrared spectroscopy with the Large Binocular Telescope together with multiwavelength observations from ultraviolet to millimeter wavelengths together suggest that J1224+5555 harbors a highly absorbed AGN with an intrinsic absorption of ~NH >10^24 cm^-2. The hard X-ray luminosity of the putative AGN corrected for absorption is L{2-10~keV}~3x10^42 ergs/s, which, depending on the bolometric correction factor, corresponds to a bolometric luminosity of the AGN of 6x10^43ergs/s - 3x10^44 erg/s, and a lower mass limit for the black hole of MBH~2x10^6 Msun, based on the Eddington limit.
description: Accepted to ApJ, 14 pages, 7 figures
Null pseudo-isotropic Lagrangian surfaces
Creators: name: Carriazo, Alfonso
name: Martín-Molina, Verónica
name: Vrancken, Luc
Publisher: name: arXiv
Year: 2016
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 53B25, 53B20

description: In this paper we will show that a Lagrangian, Lorentzian surface $M^2_1$ in a complex pseudo space form $\widetilde M^2_1 (4c)$ is pseudo-isotropic if and only if $M$ is minimal. Next we will obtain a complete classification of all Lagrangian, Lorentzian surfaces which are lightlike pseudo-isotropic but not pseudo-isotropic.
description: 15 pages
Search-based Planning of Dynamic MAV Trajectories Using Local Multiresolution State Lattices
Creators: name: Schleich, Daniel
name: Behnke, Sven
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Search-based methods that use motion primitives can incorporate the system's dynamics into the planning and thus generate dynamically feasible MAV trajectories that are globally optimal. However, searching high-dimensional state lattices is computationally expensive. Local multiresolution is a commonly used method to accelerate spatial path planning. While paths within the vicinity of the robot are represented at high resolution, the representation gets coarser for more distant parts. In this work, we apply the concept of local multiresolution to high-dimensional state lattices that include velocities and accelerations. Experiments show that our proposed approach significantly reduces planning times. Thus, it increases the applicability to large dynamic environments, where frequent replanning is necessary.
description: Accepted for IEEE International Conference on Robotics and Automation (ICRA), Xi'an, China, to appear June 2021
Automated freezing of gait assessment with marker-based motion capture and multi-stage spatial-temporal graph convolutional neural networks
Creators: name: Filtjens, Benjamin
name: Ginis, Pieter
name: Nieuwboer, Alice
name: Slaets, Peter
name: Vanrumste, Bart
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Freezing of gait (FOG) is a common and debilitating gait impairment in Parkinson's disease. Further insight into this phenomenon is hampered by the difficulty to objectively assess FOG. To meet this clinical need, this paper proposes an automated motion-capture-based FOG assessment method driven by a novel deep neural network. Automated FOG assessment can be formulated as an action segmentation problem, where temporal models are tasked to recognize and temporally localize the FOG segments in untrimmed motion capture trials. This paper takes a closer look at the performance of state-of-the-art action segmentation models when tasked to automatically assess FOG. Furthermore, a novel deep neural network architecture is proposed that aims to better capture the spatial and temporal dependencies than the state-of-the-art baselines. The proposed network, termed multi-stage spatial-temporal graph convolutional network (MS-GCN), combines the spatial-temporal graph convolutional network (ST-GCN) and the multi-stage temporal convolutional network (MS-TCN). The ST-GCN captures the hierarchical spatial-temporal motion among the joints inherent to motion capture, while the multi-stage component reduces over-segmentation errors by refining the predictions over multiple stages. The experiments indicate that the proposed model outperforms four state-of-the-art baselines. Moreover, FOG outcomes derived from MS-GCN predictions had an excellent (r=0.93 [0.87, 0.97]) and moderately strong (r=0.75 [0.55, 0.87]) linear relationship with FOG outcomes derived from manual annotations. The proposed MS-GCN may provide an automated and objective alternative to labor-intensive clinician-based FOG assessment. Future work is now possible that aims to assess the generalization of MS-GCN to a larger and more varied verification cohort.
Dynamic optimization and its relation to classical and quantum constrained systems
Creators: name: Contreras, Mauricio
name: Pellicer, Rely
name: Villena, Marcelo
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Finance (q-fin.MF)
subject: FOS: Economics and business

description: We study the structure of a simple dynamic optimization problem consisting of one state and one control variable, from a physicist's point of view. By using an analogy to a physical model, we study this system in the classical and quantum frameworks. Classically, the dynamic optimization problem is equivalent to a classical mechanics constrained system, so we must use the Dirac method to analyze it in a correct way. We find that there are two second-class constraints in the model: one fix the momenta associated with the control variables, and the other is a reminder of the optimal control law. The dynamic evolution of this constrained system is given by the Dirac's bracket of the canonical variables with the Hamiltonian. This dynamic results to be identical to the unconstrained one given by the Pontryagin equations, which are the correct classical equations of motion for our physical optimization problem. In the same Pontryagin scheme, by imposing a closed-loop $λ$-strategy, the optimality condition for the action gives a consistency relation, which is associated to the Hamilton-Jacobi-Bellman equation of the dynamic programming method. A similar result is achieved by quantizing the classical model. By setting the wave function $Ψ(x,t) = e^{iS(x,t)}$ in the quantum Schrödinger equation, a non-linear partial equation is obtained for the $S$ function. For the right-hand side quantization, this is the Hamilton-Jacobi-Bellman equation, when $S(x,t)$ is identified with the optimal value function. Thus, the Hamilton-Jacobi-Bellman equation in Bellman's maximum principle, can be interpreted as the quantum approach of the optimization problem.
A data driven network approach to rank countries production diversity and food specialization
Creators: name: Tu, Chengyi
name: Carr, Joel
name: Suweis, Samir
Publisher: name: arXiv
Year: 2016
Subjects: subject: Physics and Society (physics.soc-ph)
subject: General Finance (q-fin.GN)
subject: FOS: Physical sciences
subject: FOS: Economics and business

description: The easy access to large data sets has allowed for leveraging methodology in network physics and complexity science to disentangle patterns and processes directly from the data, leading to key insights in the behavior of systems. Here we use to country specific food production data to study binary and weighted topological properties of the bipartite country-food production matrix. This country-food production matrix can be: 1) transformed into overlap matrices which embed information regarding shared production of products among countries, and or shared countries for individual products, 2) identify subsets of countries which produce similar commodities or subsets of commodities shared by a given country allowing for visualization of correlations in large networks, and 3) used to rank country's fitness (the ability to produce a diverse array of products weighted on the type of food commodities) and food specialization (quantified on the number of countries producing that food product weighted on their fitness). Our results show that, on average, countries with high fitness producing highly specialized food commodities also produce low specialization goods, while nations with low fitness producing a small basket of diverse food products, typically produce low specialized food commodities.
Hearing gravity from the cosmos: GWTC-2 probes general relativity at cosmological scales
Creators: name: Ezquiaga, Jose María
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Gravitational-wave (GW) catalogs are rapidly increasing in number, allowing for robust statistical analyses of the population of compact binaries. Nonetheless, GW inference of cosmology has typically relied on additional electromagnetic counterparts or galaxy catalogs. I present a new probe of cosmological modifications of general relativity with GW data only. I focus on deviations of the GW luminosity distance constrained with the astrophysical population of binary black holes (BBHs). The three key observables are 1) the number of events as a function of luminosity distance, 2) the stochastic GW background of unresolved binaries and 3) the location of any feature in the source mass distribution, such as the pair instability supernova (PISN) gap. Despite a priori degeneracies between modified gravity and the unknown evolution of the merger rate and source masses, a large damping of the GW amplitude could be falsifiable since as redshift grows it reduces the events and lowers the edges of the PISN gap, which is against standard astrophysical expectations. Applying a hierarchical Bayesian analysis to the current LIGO--Virgo catalog (GWTC-2), the strongest constraints to date are placed on deviations from the GW luminosity distance, finding $c_{_M}=-3.2^{+3.4}_{-2.0}$ at $68\%$ C.L., which is $\sim10$ times better than multi-messenger GW170817 bounds. These modifications also affects the determination of the BBH masses, which is crucial to accommodate the high-mass binary GW190521 away from the PISN gap. In this analysis it is found that the maximum mass of $99\%$ of the population shifts to lower masses with increased uncertainty, $m_{99\%}=46.2^{+11.4}_{-9.1}M_\odot$ at $68\%$ C.L. Testing gravity at large scales with the population of BBHs will become increasingly relevant with future catalogs, providing an independent and self-contained test of the standard cosmological model.
description: 5+3 pages, 3+1 figures. Comments welcome!
Photometric and period investigation of the late F-type overcontact binary II UMa
Creators: name: Zhou, X.
name: Qian, S. -B.
name: Zhang, J.
name: Zhang, B.
name: Kreiner, J.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: II UMa is a late F-type (F5) contact binary with a close-in tertiary and a distant visual companion. According to the four-color ($B$ $V$ $R_c$ $I_c$) light curves' solutions of II UMa, it is a high fill-out (f=$86.6\,\%$) and low mass ratio ($q = 0.172$) contact binary system, which indicate that it is at the late evolutionary stage of late-type tidal-locked binary stars. The mass of the primary star and secondary one are calculated to be $M_1 = 1.99M_\odot$, $M_2 = 0.34M_\odot$. The primary star has evolved from ZAMS, but it is still before TAMS, and the secondary star is even more evolved. Considering the mass ratio ($M_3/M_1 = 0.67$) obtained by spectroscopic observations, the mass of the close-in tertiary is estimated to be $M_3 = 1.34M_\odot$. The period variations of the binary system is investigated for the first time. According to the observed-calculated ($O$-$C$) curve analysis, a continuous period increase at a rate of $dP/dt=4.88\times{10^{-7}}day\cdot year^{-1}$ is determined. It may be just a part of a cyclic period change, or the combinational period change of a parabolic variation and a cyclic one. More times of minimum light are needed to confirm this. The presence of the tertiary component may play an important role in the formation and evolution of this binary system by drawing angular momentum from the central system during the pre-contact stage.
description: 12 pages, 4 figures. arXiv admin note: text overlap with arXiv:1608.00210
Die Segmentspaltverknöcherung nach Unterkieferrekonstruktion mit dem Fibulatransplantat unter Berücksichtigung biomechanischer Eigenschaften verschiedener Osteosynthesen
Creators: name: Steffen, Claudius
Publisher: name: Charité - Universitätsmedizin Berlin
Year: 2024
Subjects: subject: mandible reconstruction
subject: patient specific implants
subject: biomechanics
subject: non-union
subject: Fibula-Transplantat
subject: Pseudarthrosis
subject: osteosynthesis
subject: 600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::610 Medizin und Gesundheit

description: Die Studien der vorliegenden Arbeit analysierten Untersuchungsmethoden für die Segmentspaltverknöcherung nach Unterkieferrekonstruktionen mit Fibulatransplantaten, sowie die biomechanischen Eigenschaften von etablierten und alternativen Osteosynthesen. Mit der volumetrischen Messung der Segmentspaltverknöcherung konnte eine zuverlässige und objektive Methodik neu eingeführt werden; eine mit dieser Bewertungsmethode durchgeführte retrospektive Untersuchung an Patienten identifizierte den anterioren Segmentspalt bei Unterkieferrekonstruktionen mit einem Fibulatransplantat und der Osteosynthese mit einer CAD/CAM Rekonstruktionsplatte als unabhängigen Risikofaktor für eine Pseudarthrose. Hierdurch wurde ein klarer Hinweis auf die Relevanz der Biomechanik für die Verknöcherung nach Unterkieferrekonstruktionen geliefert, was zusätzlich durch FEA dieser Arbeit untermauert werden konnte. Klinisch sollte der anteriore Spalt daher zukünftig bei Fragen rund um eine mögliche dentale Rehabilitation inklusive Materialentfernung besonders intensiv betrachtet werden. Mittels biomechanischer Untersuchungen an einem Unterkieferrekonstruktionsmodell konnte eine erhöhte IOM von konventionellen und CAD/CAM Miniplatten im Vergleich zu einer CAD/CAM Rekonstruktionsplatte zur Osteosynthese von Fibulatransplantaten nachgewiesen werden. Vor dem Hintergrund von postoperativ reduzierten Kaukräften, der Notwendigkeit einer gewissen axialen Belastung des Segmentspaltkallus und klinisch erhöhten Pseudarthroseraten bei CAD/CAM Rekonstruktionsplatten scheint eine mäßige IOM wie bei Osteosynthesen mit Miniplatten vorteilhaft zu sein. Weitere FEA zeigten, dass der kombinierte Einsatz von CAD/CAM Miniplatten im anterioren Bereich und einer kleinen posterioren CAD/CAM Rekonstruktionsplatte sowohl aus biomechanischer als auch aus klinischer Sicht günstig sein dürfte. Hingegen beeinflusst offenbar eine Veränderung des Schraubensystems die IOM nicht maßgeblich. Osteosynthesen mit alternativen Materialien wie PEEK oder PLA scheinen allgemein nicht für Unterkieferrekonstruktionen geeignet zu sein, sodass weitere Materialalternativen wie Magnesium, Zink oder Seide von Interesse sind. Für eine zukünftige biomechanische Optimierung der Osteosynthese mit dem Ziel der Verringerung der Pseudarthroserate sind weitere Studien auf biomechanischer und klinischer Ebene erforderlich, insbesondere weil sich die Biomechanik im Segmentspalt durch die Osteosyntheseart, Kaukräfte, und die Anatomie der Rekonstruktion maßgeblich verändert.
MPEC 2023-R197 : COMET C/2023 R1 (PANSTARRS)
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: COMET C/2023 R1 (PANSTARRS)

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
The Gamma-ray Cherenkov Telescope for the Cherenkov Telescope Array
Creators: name: Tibaldo, L.
name: Abchiche, A.
name: Allan, D.
name: Amans, J. -P.
name: Armstrong, T. P.
name: Balzer, A.
name: Berge, D.
name: Boisson, C.
name: Bousquet, J. -J.
name: Brown, A. M.
name: Bryan, M.
name: Buchholtz, G.
name: Chadwick, P. M.
name: Costantini, H.
name: Cotter, G.
name: Daniel, M. K.
name: De Franco, A.
name: De Frondat, F.
name: Dournaux, J. -L.
name: Dumas, D.
name: Ernenwein, J. -P.
name: Fasola, G.
name: Funk, S.
name: Gironnet, J.
name: Graham, J. A.
name: Greenshaw, T.
name: Hervet, O.
name: Hidaka, N.
name: Hinton, J. A.
name: Huet, J. -M.
name: Jankowsky, D.
name: Jegouzo, I.
name: Jogler, T.
name: Kraus, M.
name: Lapington, J. S.
name: Laporte, P.
name: Lefaucheur, J.
name: Markoff, S.
name: Melse, T.
name: Mohrmann, L.
name: Molyneux, P.
name: Nolan, S. J.
name: Okumura, A.
name: Osborne, J. P.
name: Parsons, R. D.
name: Rosen, S.
name: Ross, D.
name: Rowell, G.
name: Rulten, C. B.
name: Sato, Y.
name: Sayede, F.
name: Schmoll, J.
name: Schoorlemmer, H.
name: Servillat, M.
name: Sol, H.
name: Stamatescu, V.
name: Stephan, M.
name: Stuik, R.
name: Sykes, J.
name: Tajima, H.
name: Thornhill, J.
name: Trichard, C.
name: Vink, J.
name: Watson, J. J.
name: White, R.
name: Yamane, N.
name: Zech, A.
name: Zink, A.
name: Zorn, J.
name: Consortium, the CTA
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The Cherenkov Telescope Array (CTA) is a forthcoming ground-based observatory for very-high-energy gamma rays. CTA will consist of two arrays of imaging atmospheric Cherenkov telescopes in the Northern and Southern hemispheres, and will combine telescopes of different types to achieve unprecedented performance and energy coverage. The Gamma-ray Cherenkov Telescope (GCT) is one of the small-sized telescopes proposed for CTA to explore the energy range from a few TeV to hundreds of TeV with a field of view $\gtrsim 8^\circ$ and angular resolution of a few arcminutes. The GCT design features dual-mirror Schwarzschild-Couder optics and a compact camera based on densely-pixelated photodetectors as well as custom electronics. In this contribution we provide an overview of the GCT project with focus on prototype development and testing that is currently ongoing. We present results obtained during the first on-telescope campaign in late 2015 at the Observatoire de Paris-Meudon, during which we recorded the first Cherenkov images from atmospheric showers with the GCT multi-anode photomultiplier camera prototype. We also discuss the development of a second GCT camera prototype with silicon photomultipliers as photosensors, and plans toward a contribution to the realisation of CTA.
description: 6 paqes, 4 figures. To appear in the Proceedings of the 6th International Symposium on High-Energy Gamma-Ray Astronomy (July 11-15, 2016, Heidelberg, Germany)
Sparse Layered MIMO with Iterative Detection
Creators: name: Dinan, Mohamad H.
name: Perovic, Nemanja Stefan
name: Flanagan, Mark F.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Theory (cs.IT)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: In this paper, we propose a novel transmission scheme, called sparse layered MIMO (SL-MIMO), that combines non-orthogonal transmission and singular value decomposition (SVD) precoding. Nonorthogonality in SL-MIMO allows re-using of the eigen-channels which improves the spectral efficiency and error rate performance of the system through enhancing the coding gain and diversity gain. We also present a low-complexity message-passing (MP) detector for the proposed SL-MIMO system which performs quite close to maximum likelihood (ML). The joint moment generating function (MGF) of the ordered eigenvalues is calculated and used to derive a closed-form upper bound on the average word error probability (AWEP) of the SL-MIMO system, and this derived expression is then used to analyze the diversity gain of the system. We use our analytical results to design sub-optimal codebooks to minimize the error rate of the SL-MIMO system. Simulation results in 4x4 and 6x6 multiple-input multiple-output (MIMO) systems with 4-ary, 16-ary, and 64-ary constellations show that our proposed SL-MIMO scheme outperforms competing approaches such as X- and Y-codes in terms of system error rate performance. SL-MIMO has 5.6 dB advantage compared to X-codes and 4.7 dB advantage compared to Y-codes in 6x6 MIMO system with a 64-ary constellation.
description: 14 pages (double), 7 figures, 1 table