Modeling, simulation, and stability of a hydraulic load-sensing pump system with investigation of a hard nonlinearity in the pump displacement control system

Certain types of Load-Sensing (LS) pumps utilize a hydro-mechanical control system designed to regulate the pressure difference, or margin pressure, between the inlet and outlet of a flow control valve. With a constant margin pressure, predictable flow control and improved efficiency can be achieved by controlling the orifice area of the flow control valve. Instability due to limit cycles (sustained oscillations) that stem from nonlinearities within the system is a common issue related to hydraulic LS systems. In this work, the stability of the pressure control system was investigated using describing function analysis. Describing function analysis is a method used to approximate a nonlinearity within a nonlinear system and was conducted to predict the existence and stability of limit cycles that occur due to saturation nonlinearities within the mechanical components of the LS system. A combination of linear and nonlinear analysis and modeling was employed to assess the stability of a particular LS pump system. Among many nonlinearities present in the hydro-mechanical LS system, of particular interest was the saturation inherent in the actuator that is used to displace the pump swash plate and the saturation within the 3-way spool valve that permits flow to reach the actuator. This saturation nonlinearity was believed to be a problematic source for limit cycles that tend to appear in LS systems. A comprehensive nonlinear model was developed as the foundation for this research as it was used for validation in direct comparison to experimentally acquired data. The nonlinear model proved to be precise and accurate in matching to the experimental test bed response based on the data that was gathered. The acquired data was compared to the NL model simulation through a root mean squared error evaluation and frequency response analysis. The nonlinear model was then used to generate a linearized model necessary for stability analysis. The saturation nonlinearities for two separate mechanical systems were isolated from

Devotions for Advent 2022 Canticles of Luke

Each week of this Advent devotional will focus on one of the four Lukan canticles, putting it in its context as well as making connections to other portions of Scripture. At the end of this Advent season, may we, like those who have gone before us, “sing to the Lord, bless his name; tell of his salvation from day to day” (Ps. 96:2). Many thanks to all the CSL and CTSFW students who contributed devotional reflections. A special note of thanks to my counterpart, Zachary Roll, who organized this effort at Concordia Seminary, St. Louis who has been a joy to work with and to get to know. A final note of thanks to Kim Hosier in the print shop and Rev. Dr. Paul Grime for their aid in completing this devotional booklet.https://scholar.csl.edu/osp/1021/thumbnail.jp

Associations of Facial Proportionality, Attractiveness, and Character Traits.

Background: Facial proportionality and symmetry are positively associated with perceived levels of facial attractiveness. Objective: The aims of this study were to confirm and extend the association of proportionality with perceived levels of attractiveness and character traits and determine differences in attractiveness and character ratings between "anomalous" and "typical" faces using a large dataset. Methods: Ratings of 597 unique individuals from the Chicago Face Database were used. A formula was developed as a proxy of relative horizontal proportionality, where a proportionality score of "0" indicated perfect proportionality and more negative scores indicated less proportionality. Faces were categorized as "anomalous" or "typical" by 2 independent reviewers based on physical features. Results: Across the ratings for all faces, Spearman correlations revealed greater proportionality was associated with attractiveness ( ρ = 0.292, P \u3c 0.001) and trustworthiness ( ρ = 0.193, P \u3c 0.001), while lesser proportionality was associated with impressions of anger (ρ = 0.132, P = 0.001), dominance (ρ = 0.259, P \u3c 0.001), and threateningness ( ρ = 0.234, P \u3c 0.001). Mann-Whitney U tests revealed the typical cohort had significantly higher levels of proportionality (-13.98 versus -15.14, P = 0.030) and ratings of attractiveness (3.39 versus 2.99, P \u3c 0.001) and trustworthiness (3.48 versus 3.35, P \u3c 0.001). Conclusions: This study demonstrated that facial proportionality is not only significantly associated with higher ratings of attractiveness, but also associated with judgements of trustworthiness. Proportionality plays a role in evoking negative attributions of personality characteristics to people with facial anomalies

A Spectroscopic Road Map for Cosmic Frontier: DESI, DESI-II, Stage-5

In this white paper, we present an experimental road map for spectroscopic experiments beyond DESI. DESI will be a transformative cosmological survey in the 2020s, mapping 40 million galaxies and quasars and capturing a significant fraction of the available linear modes up to z=1.2. DESI-II will pilot observations of galaxies both at much higher densities and extending to higher redshifts. A Stage-5 experiment would build out those high-density and high-redshift observations, mapping hundreds of millions of stars and galaxies in three dimensions, to address the problems of inflation, dark energy, light relativistic species, and dark matter. These spectroscopic data will also complement the next generation of weak lensing, line intensity mapping and CMB experiments and allow them to reach their full potential.Comment: Contribution to Snowmass 202

Highlights From the Annual Meeting of the American Epilepsy Society 2022

With more than 6000 attendees between in-person and virtual offerings, the American Epilepsy Society Meeting 2022 in Nashville, felt as busy as in prepandemic times. An ever-growing number of physicians, scientists, and allied health professionals gathered to learn a variety of topics about epilepsy. The program was carefully tailored to meet the needs of professionals with different interests and career stages. This article summarizes the different symposia presented at the meeting. Basic science lectures addressed the primary elements of seizure generation and pathophysiology of epilepsy in different disease states. Scientists congregated to learn about anti-seizure medications, mechanisms of action, and new tools to treat epilepsy including surgery and neurostimulation. Some symposia were also dedicated to discuss epilepsy comorbidities and practical issues regarding epilepsy care. An increasing number of patient advocates discussing their stories were intertwined within scientific activities. Many smaller group sessions targeted more specific topics to encourage member participation, including Special Interest Groups, Investigator, and Skills Workshops. Special lectures included the renown Hoyer and Lombroso, an ILAE/IBE joint session, a spotlight on the impact of Dobbs v. Jackson on reproductive health in epilepsy, and a joint session with the NAEC on coding and reimbursement policies. The hot topics symposium was focused on traumatic brain injury and post-traumatic epilepsy. A balanced collaboration with the industry allowed presentations of the latest pharmaceutical and engineering advances in satellite symposia

Genome-wide meta-analyses reveal novel loci for verbal short-term memory and learning

Understanding the genomic basis of memory processes may help in combating neurodegenerative disorders. Hence, we examined the associations of common genetic variants with verbal short-term memory and verbal learning in adults without dementia or stroke (N = 53,637). We identified novel loci in the intronic region of CDH18, and at 13q21 and 3p21.1, as well as an expected signal in the APOE/APOC1/TOMM40 region. These results replicated in an independent sample. Functional and bioinformatic analyses supported many of these loci and further implicated POC1. We showed that polygenic score for verbal learning associated with brain activation in right parieto-occipital region during working memory task. Finally, we showed genetic correlations of these memory traits with several neurocognitive and health outcomes. Our findings suggest a role of several genomic loci in verbal memory processes.Peer reviewe

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV

Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

Peer reviewe