bluuebunny/crossref_metadata_2025_split huggingface dataset:
Learning Hyperparameters in Efficient Spatial Model by Robotic Sensors
Authors: Jeong Jinho , Jeon Soo , Choi Jongeun 
Published: November 2019

Abstract
Recently, a new class of spatial models over a continuum domain that builds on hidden Gaussian Markov Random Fields (GMRFs) was proposed for resource-constrained networked mobile robots dealing with non-stationary physical processes. The hidden GMRF was realized with respect to a proximity graph over a surveillance region. In this paper, we investigate learning strategies based on the maximum likelihood (ML) and the maximum a posteriori (MAP) estimators to find the locational generating points for the spatial model so that mobile robots can efficiently make the prediction. Some promising simulation results and future research directions are discussed.
Comparison of Estimation Techniques for the Crankshaft Dynamics of an Opposed Piston Engine
Authors: Drallmeier Joseph A. , Siegel Jason B. , Stefanopoulou Anna G. 
Published: November 2019

Abstract
This study provides a comparison of a linear and unscented Kalman filter to estimate the dynamics of a two-stroke opposed piston engine. These engines maintain several advantages over conventional internal combustion engines including reduced heat transfer, higher power to weight ratio, and a larger expansion ratio. Additionally, a crank angle phasing is introduced between the two cranks to improve scavenging efficiency. However, the coupling of the two crankshafts through a large geartrain can cause high amounts of noise and vibration harshness (NVH) and mechanical efficiency losses. By removing the geartrain and controlling the decoupled crankshafts with motor-generators, the NVH can be minimized while maintaining the benefits of crank angle phasing. To control the input torque of the motors to the engine, accurate estimations of the crankshaft position and dynamics are necessary. While the unscented Kalman filter exhibits lower estimation error, the filter is sensitive to model uncertainty relating to cylinder pressure, demanding further investigation of the robustness of the nonlinear filter.
Dynamic Design Optimization for Thermal Management: A Case Study on Shell and Tube Heat Exchangers
Authors: Nash Austin L. , Jain Neera 
Published: November 2019

Abstract
We present a new methodology for designing a heat exchanger that explicitly considers both static and transient performance characteristics. The proposed approach leverages 1) a highly detailed, albeit static model that captures the complex nonlinear relationship between heat exchanger geometry and heat transfer coefficients, and 2) a reduced-order dynamic model of the heat exchanger that approximates the geometry detailed in the static model. In order to optimize the component design for both static and transient performance metrics, pole locations of the corresponding linearized model are penalized in the cost function of the proposed optimization algorithm in order to move dominant poles further into the left half complex plane. Through a simulated case study for a shell and tube heat exchanger, we demonstrate how the proposed algorithm exploits the trade off between static design metrics, including mass and footprint, and the rate at which heat is removed from the primary fluid.
Sub-Optimal Tracking in Switched Systems With Controlled Subsystems and Fixed-Mode Sequence Using Approximate Dynamic Programming
Authors: Sardarmehni Tohid , Song Xingyong 
Published: November 2019

Abstract
Optimal tracking in switched systems with controlled subsystem and Discrete-time (DT) dynamics is investigated. A feedback control policy is generated such that a) the system tracks the desired reference signal, and b) the optimal switching time instants are sought. For finding the optimal solution, approximate dynamic programming is used. Simulation results are provided to illustrate the effectiveness of the solution.
Modelling and Simulation of Perching With a Quadrotor Aerial Robot With Passive Bio-Inspired Legs and Feet
Authors: Dunlop David J. , Minor Mark A. 
Published: November 2019

Abstract
Publisher’s Note:
This paper was selected for publication in ASME Letters in Dynamic Systems and Control.
https://www.asmedigitalcollection.asme.org/lettersdynsys/article/doi/10.1115/1.4046778/1082076/Modeling-and-Simulation-of-Perching-With-a
Modeling Height Profile for Drop-on-Demand Print of UV Curable Ink
Authors: Wu Yumeng , Chiu George 
Published: November 2019

Abstract
This paper proposes a height profile model for drop-on-demand printing of UV curable ink. Existing models include superposition of single drops, numerical models, and graphic-based model. They are either too complicated or over simplified. Graphic model intends to find a sweet spot in between, however, accuracy is marginally improved from superposition model while it demands more computation. The proposed model aims to achieve the same as graphic model by introducing volume and area propagation matrices to reflect the localized ink flow from higher location to the lower, while avoiding the detailed physics behind it. This model assumes a constant volume and area propagation of subsequent drop due to height profile difference. It is validated with experiments on single drop, 2-drop and 3-drop line printing. Stability of this model is analyzed.. Using root mean square (RMS) error as benchmark, proposed model achieves 6.6% along the center row and 7.4% overall, better than existing models.
Texas Sport Leadership Consultants, LLC: A Case of Cases
Authors: Sparvero Emily , Griffiths Randall , Tingle Jacob 
Published: November 2019

This immersive, multi-case experience consists of four distinct cases and one meta-case that require students to engage with several organizational behavior topics. First, the meta-case takes the form of Texas Sport Leadership Consultants (TSLC), a fictitious company which consults with local sport management professionals in a variety of contexts. Students participate as temporary members of the company to analyze the issues and challenges associated with working as a member of TSLC. TSLC work groups are hired by four different clients, each of whom has a unique organizational behavior challenge. These clients include: (1) a combat-oriented sport company; (2) a company that provides luxury sport experiences for business travelers; (3) Division II athletic directors; and (4) a minor league hockey team. The clients face challenges related to mission and vision, group dynamics, change leadership, and power and politics. Student groups analyze the case and provide recommendations, which are presented as the basis for discussion among TSLC colleagues.
Sporulation and Germination in Clostridial Pathogens
Authors: Shen Aimee , Edwards Adrianne N. , Sarker Mahfuzur R. , Paredes-Sabja Daniel 
Published: November 2019

ABSTRACT

As obligate anaerobes, clostridial pathogens depend on their metabolically dormant, oxygen-tolerant spore form to transmit disease. However, the molecular mechanisms by which those spores germinate to initiate infection and then form new spores to transmit infection remain poorly understood. While sporulation and germination have been well characterized in
Bacillus subtilis
and
Bacillus anthracis
, striking differences in the regulation of these processes have been observed between the bacilli and the clostridia, with even some conserved proteins exhibiting differences in their requirements and functions. Here, we review our current understanding of how clostridial pathogens, specifically
Clostridium perfringens
,
Clostridium botulinum
, and
Clostridioides difficile
, induce sporulation in response to environmental cues, assemble resistant spores, and germinate metabolically dormant spores in response to environmental cues. We also discuss the direct relationship between toxin production and spore formation in these pathogens.
Global mercury enrichment in Valanginian sediments supports a volcanic trigger for the Weissert episode
Authors: Charbonnier* Guillaume , Adatte Thierry , Duchamp-Alphonse Stéphanie , Spangenberg Jorge E. , Föllmi Karl B. 
Published: November 2019

ABSTRACT
Recently, a set of mercury (Hg) anomalies in Valanginian sediments recovered from European sections demonstrated that an important magmatic pulse occurred at the onset of the Weissert episode. In this study, we report the distribution of Hg contents near the onset of the Weissert episode from localities outside of Europe, in the proto–Atlantic Ocean (Blake Bahama and Cap Hatteras Basins, Deep Sea Drilling Project [DSDP] Holes 534A and 603B) and southern Tethys Ocean (Argo Abyssal Plain, Ocean Drilling Program [ODP] Hole 765C), in order to evaluate the global impact of volcanism during the Valanginian. In addition, we also reinvestigated the Orpierre and Angles sections of the Vocontian Basin at a very high time resolution, to examine the potential impact of regional volcanic activity during that time interval. The onset of the Weissert episode in the proto-Atlantic and in the southern Tethyan cores is marked by significant increases in Hg contents. The persistence of the Hg anomaly in Hg/total organic carbon and Hg/Al ratios suggests that Hg enrichments were not primarily controlled by runoff processes and/or redox conditions, but instead indicate an increase in volcanic activity. The Hg enrichments recorded from localities outside of Europe at different latitudes were correlated to those previously observed in European sections, thereby confirming the presence of a global Hg peak at the onset of the Weissert episode. This peak was probably related to the emplacement of the Paraná-Etendeka large igneous province, suggesting a key role for volcanic activity during the Valanginian global environmental perturbations. In coeval intervals in the Vocontian Basin, Hg records show abrupt and short-lived enrichments, which correspond in the sedimentary successions to a goethite-rich ocher-colored layer. Two regional processes could explain Hg deposition and sequestration in this region: increased Hg sequestration by organic matter production in an oxygen-depleted environment, and/or the presence of regional volcanic activity, which is also indicated by the occurrence of a distal volcanic ash layer.
Integrated mineralogical and rock magnetic study of Deccan red boles
Authors: Font* Eric , Adatte Thierry , Abrajevitch Alexandra , Mirão José , Sharma Nikhil , Sordet Valentin , Andrade Mariana 
Published: November 2019

ABSTRACT
We conducted a detailed rock magnetic and mineralogical study of bole beds from the Deccan magmatic province, India. Magnetic susceptibility of 15 bole beds showed two contrasting patterns, with susceptibility values either increasing or decreasing up the profile. We then focused on two representatives red boles located in the Western Ghats, the RBB and RBAN profiles, to unravel the nature and origin of these contrasting magnetic susceptibility patterns. The presence of smectite argues against significant secondary thermal alterations. Major-elemental compositions obtained by X-ray fluorescence spectrometry of RBB and RBAN red boles are comparable to the parent basalt and show significant and typical depletion of mobile elements such as sodium and calcium compared to the parent basalt. The Ti/Al ratio of both the red boles and their overlying clay layers is close to the typical value of Deccan basalt (0.2), suggesting that the material of the red boles has been derived from weathering of the parent basalt. The chemical index of alteration varies from 40–50 in the parent basalt to 80–90 at the top of the bole beds, consistent with moderate to intense weathering of the bole beds. However, similar to other Deccan bole beds, indices of lateritization below 50 suggest that the state of lateritization has not been reached. Although the RBB and RBAN profiles share similar mineralogical signatures, their magnetic mineral assemblages are distinctly different. In the RBB profile, magnetic susceptibility decreases up-profile as a result of oxidation/dissolution of primary titanomagnetite inherited from the parent basalt, with subsequent formation of pedogenic hematite and superparamagnetic particles. In contrast, magnetic susceptibility in the RBAN profile, which contains magnetite, some hematite, and goethite, increases up-profile. The increase in the magnetic signal is mainly due to the increasing amounts of phyllosilicate and goethite, while the content of magnetite and hematite remains constant along the profile. We attribute the variation in the magnetic mineral assemblage to contrasting humid and dry environments during weathering, leading to the preferential formation of goethite or hematite, respectively. The combined mineralogical and rock magnetic data suggest the existence of a single weathering profile involving soil formation in the two studied red boles, with few or no contributions from an external source.
PRDX3 is associated with metastasis and poor survival in uveal melanoma
Authors: Ramasamy Pathma , Larkin Anne-Marie , Linge Annett , Tiernan Damien , McAree Fionnuala , Horgan Noel , Moriarty Paul , Beatty Stephen , Murphy Conor C , Clynes Martin , Kennedy Susan , Meleady Paula 
Published: November 2019

AimsUveal melanoma (UM) is the most common primary intraocular malignancy in adults, and 40% develop fatal metastatic disease. Overexpression of thioredoxin-dependent peroxidase reductase (PRDX3) has been implicated in several cancers, including prostate, breast, colorectal and lung cancer. The aim of this study was to compare the immunohistochemical expression of PRDX3 in formalin-fixed, paraffin-embedded (FFPE) primary UM tissues of patients who did and did not develop metastatic disease.MethodsImmunohistochemical staining of PRDX3 was performed on FFPE tissue microarray samples of 92 primary UM tumours from patients who did and did not develop metastatic disease. The immunohistochemical staining was assessed by two observers who were blinded to all clinicopathological and cytogenetic details including metastatic/non-metastatic information. Based on a scoring system, expression of PRDX3 was graded as high or low.ResultsThere were 55 tumours (59.8%) from patients who developed metastatic disease, while 37 (40.2%) were from patients who did not develop metastasis. A statistically significant difference in PRDX3 expression was observed in patients who did and did not develop metastasis (p=0.001). A significant positive correlation between high PRDX3 expression and metastasis was observed (p=0.001). A significant negative correlation between PRDX3 expression and survival was found (p=0.005). Kaplan-Meier survival analysis showed a statistically significant difference in overall survival between tumours that demonstrated low and high expression of PRDX3 (67.61 vs 130.64 months, respectively, p=0.013).ConclusionsHigh immunohistochemical expression of PRDX3 in primary UM tissue is associated with metastasis and poor survival.
Prognostic value of von Willebrand factor for patients with atrial fibrillation: a meta-analysis of prospective cohort studies
Authors: Ye Yuan-Zheng , Chang Ya-Fei , Wang Bao-Zhu , Ma Yi-Tong , Ma Xiang 
Published: November 2019

AbstractBackgroundIt is unknown whether an abnormal level of von Willebrand factor (vWF) is correlated with the prognosis of patients with atrial fibrillation (AF) and current findings are controversial. This meta-analysis aimed to evaluate the association between vWF levels and the clinical prognosis of patients with AF.MethodsWe searched prospective cohort studies on PubMed, Embase, Web of Science, Cochrane Library and WanFang databases for vWF and adverse events of AF from inception of the databases to July 2019. The risk ratios of all-cause death, cardiovascular death, major adverse cardiac events (MACE), stroke and bleeding prognosis in patients with AF were analysed using a fixed-effects model or random-effects model, and all included studies were evaluated with heterogeneity and publication bias analysis.ResultsTwelve studies which included 7449 patients with AF were used in the meta-analysis. The average age was 71.3 years and the average follow-up time was 3.38 years. The analysis found that high vWF levels were associated with increased risks of all-cause death (RR 1.56; 95% CI 1.16 to 2.11, p=0.00400), cardiovascular death (RR 1.91; 95% CI 1.20 to 3.03, p=0.00600), MACE (RR 1.83; 95% CI 1.28 to 2.62, p=0.00090), stroke (RR 1.69; 95% CI 1.08 to 2.64, p=0.02000) and bleeding (RR 2.01; 95% CI 1.65 to 2.45, p&lt;0.00001) in patients with AF.ConclusionsvWF is a risk factor for poor prognosis of AF, and patients with higher vWF levels have a higher risk of all-cause death, cardiovascular death, MACE, stroke and bleeding.
Fermionic response in nonlinear arcsin electrodynamics
Authors: Rai Nishal 
Published: November 2019

AbstractWe consider certain blackhole solution in non-linear arcsin electrodynamics coupled with gravity and axions. We have studied the behaviour of the fermionic operators in the dual (2+1)-dimensional theory. We consider holographic spectral function for both the backreacted solutions and probe limit over the range of physical parameters. We find that with a variation of the charge density the system changes from Fermi liquid to non-Fermi liquid and the transition point depends on the temperature.
Muon loss rates from betatron resonances at the Muon g − 2 Storage Ring at Fermilab
Authors: Tarazona D. A. , Berz M. , Makino K. 
Published: November 2019

The Muon [Formula: see text] Experiment at Fermilab (E989) is directed toward measuring the muon magnetic anomaly, [Formula: see text], with total statistical and systematic errors of 0.14 ppm. This new measurement will serve as strong probe of effects of as yet undiscovered particles beyond the Standard Model (SM), and perhaps validate or disprove other theoretical models beyond the SM. Of special interest is the reduction of muon losses from the storage ring to achieve the precision needed at the Muon [Formula: see text] Experiment. For this purpose, we have developed a detailed and precise symplectic model of the Muon [Formula: see text] Storage Ring using COSY INFINITY that considers measured inhomogeneities of the magnetic field; high-order representation of the Electrostatic Quadrupole System (EQS) electrostatic field at different stages of the experiment including fringe fields; injection to the ring based on measurements; and beam collimation. Specifically, we have performed numerical analyses of the rate of muons that are lost before they have a chance to decay for several possible configurations of the EQS in order to find the best possible scenarios that minimize muon losses and understand the resonance mechanisms that contribute to betatron and possibly spin resonances. Additionally, comparisons with measurements have permitted the determination of whether observed resonances come from anticipated features of the [Formula: see text] storage ring or from unexpected sources of error whose effect could be detrimental to the precision of E989.
Challenges in simulating beam dynamics of dielectric laser acceleration
Authors: Niedermayer Uwe , Adelmann A. , Bettoni S. , Calvi M. , Dehler M. , Ferrari E. , Frei F. , Hauenstein D. , Hermann B. , Hiller N. , Ischebeck R. , Lombosi C. , Prat E. , Reiche S. , Rivkin L. , Aßmann R. , Dorda U. , Hartl I. , Kuropka W. , Lemery F. , Marchetti B. , Mayet F. , Xuan H. , Zhu J. , Black D. S. , Broaddus P. N. , Byer R. L. , Ceballos A. , Deng H. , Fan S. , Harris J. , Hirano T. , Hughes T. W. , Jiang Y. , Langenstein T. , Leedle K. , Miao Y. , Ody A. , Pigott A. , Sapra N. , Solgaard O. , Su L. , Tan S. , Vuckovic J. , Yang K. , Zhao Z. , Boine-Frankenheim O. , Egenolf T. , Skär E. , Cesar D. , Musumeci P. , Naranjo B. , Rosenzweig J. , Shen X. , Cowan B. , England R. J. , Huang Z. , Cankaya H. , Fakhari M. , Fallahi A. , Kärtner F. X. , Feurer T. , Hommelhoff P. , Illmer J. , Li A. , Mittelbach A. , McNeur J. , Schönenberger N. , Shiloh R. , Tafel A. , Yousefi P. , Kozak M. , Qi M. , Lee Y. J. , Huang Y.-C. , Simakov E. 
Published: November 2019

Dielectric Laser Acceleration (DLA) achieves the highest gradients among structure-based electron accelerators. The use of dielectrics increases the breakdown field limit, and thus the achievable gradient, by a factor of at least 10 in comparison to metals. Experimental demonstrations of DLA in 2013 led to the Accelerator on a Chip International Program (ACHIP), funded by the Gordon and Betty Moore Foundation. In ACHIP, our main goal is to build an accelerator on a silicon chip, which can accelerate electrons from below 100 keV to above 1 MeV with a gradient of at least 100 MeV/m. For stable acceleration on the chip, magnet-only focusing techniques are insufficient to compensate the strong acceleration defocusing. Thus, spatial harmonic and Alternating Phase Focusing (APF) laser-based focusing techniques have been developed. We have also developed the simplified symplectic tracking code DLAtrack6D, which makes use of the periodicity and applies only one kick per DLA cell, which is calculated by the Fourier coefficient of the synchronous spatial harmonic. Due to coupling, the Fourier coefficients of neighboring cells are not entirely independent and a field flatness optimization (similarly as in multi-cell cavities) needs to be performed. The simulation of the entire accelerator on a chip by a Particle In Cell (PIC) code is possible, but impractical for optimization purposes. Finally, we have also outlined the treatment of wake field effects in attosecond bunches in the grating within DLAtrack6D, where the wake function is computed by an external solver.
Enhancing Personalized Recommendation by Implicit Preference Communities Modeling
Authors: Lin Xiao , Zhang Min , Liu Yiqun , Ma Shaoping 
Published: November 2019

Recommender systems aim to capture user preferences and provide accurate recommendations to users accordingly. For each user, there usually exist others with similar preferences, and a collection of users may also have similar preferences with each other, thus forming a community. However, such communities may not necessarily be explicitly given, and the users inside the same communities may not know each other; they are formally defined and named Implicit Preference Communities (IPCs) in this article. By enriching user preferences with the information of other users in the communities, the performance of recommender systems can also be enhanced.
Historical explicit ratings are a good resource to construct the IPCs of users but is usually sparse. Meanwhile, user preferences are easily affected by their social connections, which can be jointly used for IPC modeling with the ratings. However, this imposes two challenges for model design. First, the rating and social domains are heterogeneous; thus, it is challenging to coordinate social information and rating behaviors for a same learning task. Therefore, transfer learning is a good strategy for IPC modeling. Second, the communities are not explicitly labeled, and existing supervised learning approaches do not fit the requirement of IPC modeling. As co-clustering is an effective unsupervised learning approach for discovering block structures in high-dimensional data, it is a cornerstone for discovering the structure of IPCs.
In this article, we propose a recommendation model with Implicit Preference Communities from user ratings and social connections. To tackle the unsupervised learning limitation, we design a Bayesian probabilistic graphical model to capture the IPC structure for recommendation. Meanwhile, following the spirit of transfer learning, both rating behaviors and social connections are introduced into the model by parameter sharing. Moreover, Gibbs sampling-based algorithms are proposed for parameter inferences of the models. Furthermore, to meet the need for online scenarios when the data arrive sequentially as a stream, a novel online sampling-based parameter inference algorithm for recommendation is proposed. To the best of our knowledge, this is the first attempt to propose and formally define the concept of IPC.