Cool carbon stars in the halo and in dwarf galaxies: Halpha, colours, and variabiity

The population of cool carbon (C) stars located far from the galactic plane is probably made of debris of small galaxies such as the Sagittarius dwarf spheroidal galaxy (Sgr), which are disrupted by the gravitational field of the Galaxy. We aim to know this population better through spectroscopy, 2MASS photometric colours, and variability data. When possible, we compared the halo results to C star populations in the Fornax dwarf spheroidal galaxy, Sgr, and the solar neighbourhood. We first present a few new discoveries of C stars in the halo and in Fornax. The number of spectra of halo C stars is now 125. Forty percent show Halpha in emission. The narrow location in the JHK diagram of the halo C stars is found to differ from that of similar C stars in the above galaxies. The light curves of the Catalina and LINEAR variability databases were exploited to derive the pulsation periods of 66 halo C stars. A few supplementary periods were obtained with the TAROT telescopes. We confirm that the period distribution of the halo strongly resembles that of Fornax, and we found that is it very different from the C stars in the solar neighbourhood. There is a larger proportion of short period Mira/SRa variables in the halo than in Sgr, but the survey for C stars in this dwarf galaxy is not complete, and the study of their variability needs to be continued to investigate the link between Sgr and the cool halo C stars.Comment: 11 pages, 10 figures + one appendix of 26 pages; accepted for publication in Astronomy and Astrophysic

Student Support: A K-6 At-risk Program Model

The purpose of this study was to identify priority components and measurement standards of an effective K-6 At-Risk Program, then develop a resource guide for At-Risk program managers. A survey was sent to the Washington school districts with at-risk programs in place, as identified by the Student Retention and Retrieval Program handbook issued by the Office of the Superintendent of Public Instruction. The survey was successful in helping identify the most effective program components: individual and small group counseling, classroom presentations with published materials, parent education, attendance monitoring, and peer/adult tutors. Evaluation standards vary according to program components and generally rely on feedback from staff, parents, and students. The result of the study was a handbook titled, Student Support: A K-6 At-Risk Program Model

Depth-bounded Epistemic Logic

Epistemic logics model how agents reason about their beliefs and the beliefs of other agents. Existing logics typically assume the ability of agents to reason perfectly about propositions of unbounded modal depth. We present DBEL, an extension of S5 that models agents that can reason about epistemic formulas only up to a specific modal depth. To support explicit reasoning about agent depths, DBEL includes depth atoms Ead (agent a has depth exactly d) and Pad (agent a has depth at least d). We provide a sound and complete axiomatization of DBEL. We extend DBEL to support public announcements for bounded depth agents and show how the resulting DPAL logic generalizes standard axioms from public announcement logic. We present two alternate extensions and identify two undesirable properties, amnesia and knowledge leakage, that these extensions have but DPAL does not. We provide axiomatizations of these logics as well as complexity results for satisfiability and model checking. Finally, we use these logics to illustrate how agents with bounded modal depth reason in the classical muddy children problem, including upper and lower bounds on the depth knowledge necessary for agents to successfully solve the problem.Comment: In Proceedings TARK 2023, arXiv:2307.0400

Aquifères karstiques et caractéristiques physico-chimiques des eaux à l'étiage : exemple de la zone tropicale de l'hémisphère sud (Madagascar)

Deux karsts de la zone tropicale actuelle de l'hémisphère sud (Madagascar), sont tout d'abord analysés sur le plan géomorphologique. Les facteurs lithologiques, structuraux et climatiques confèrent à ces karsts des évolutions et des fonctionnements actuels nettement différenciés entre eux. Dans un deuxième temps, les caractéristiques hydrochimiques des eaux à l'étiage sont examinées et comparées à celles d'un karst de la zone tempérée (bordure méditerranéenne). De cette comparaison, il ressort que les eaux karstiques présentent des caractéristiques physico-chimiques à l'étiage très voisines quelle que soit la latitude. Par exemple, toutes les eaux sont sous-saturées en carbonates, sauf si la nappe est captive. Enfin, il est mis l'accent en conclusion sur le fait que les conditions climatiques propices à la karstification et à un haut degré d'évolution ne s'expriment pleinement que si des évènements tectoniques interviennent au cours des phénomènes de dissolution. Les morphologies karstiques hautement évoluées, comme celles de Madagascar, résultent ainsi d'une étroite complémentarité entre facteurs lithologiques, structuraux et climatiques. (Résumé d'auteur

Effect of Time of Cutting on Yield and Botanical Composition of Prairie Hay in Southeastern Nebraska

Approximately three and one-third million acres of native prairie are harvested annually in Nebraska for hay. In the four-year period 1948-1951, the State ranked first in wild hay production with an average yield of more than two and one-quarter million tons per year. This crop is an important natural resource in Nebraska\u27s livestock industry. Studies were initiated in 1945 to determine the effects of time of cutting on the yield and feeding value of prairie hay in southeastern Nebraska. The studies were continued through the summer of 1952 to determine the effects of different cutting treatments on the vigor and botanical composition of the vegetation. A separate study was initiated in 1948 and continued through 1952 to determine the effect of time of harvesting the aftermath crop in the fall on the yield of hay the following summer

A new spice-like modeling tool for bio- and electro- acoustic systems including thermoviscous effects

International audienceA dedicated toolbox has been developed within ASYGN a recent software tool that simulates aVLSI circuits at a high-level of modeling. It accounts in both time- and frequency- domain for the specific feature of bio- and electro- acoustic systems especially when some of the constituting elements are very thin or narrow. The models correspond to systems of complex equations in which some of the complex coefficients can be frequency dependent. Results are solved and viewed in real time. The tool was developed to introduce some improvement in the model of the auditory system of the cricket. In 2007 Reeve et al. designed and tested an electrical equivalent circuit based on Michelsen 1994. The latter results from two major simplification namely the absence of thermoviscous effects and of any acoustical role of a septum located in the middle of a transverse acoustic trachea. Thanks to the weak couplings the model can be subdivided into independent elements such as tubes, cavities or membranes simply connected together. Thermoviscous effects and the role of the medial septum can now be fully investigated. Our results were first validated using Matlab. Our model reveals interesting feature compared to its historical counterpart

Apports de modèles de comparaison structurelle et sémantique à la synchronisation de la maquette numérique de construction

Digital Mock-Up (DMU) is a digital, centralized and structured representation of all productions from project actors. Concerning AEC sector Digital Mock-Up for Construction (DMUC) refers to the adaptation of previous technology to this industrial field. Civil design seems however different from design of manufactured products, because of : multiplicity and heterogeneity of actors, creation of a unique product. Therefore involved processes need to be specifically analysed. This work aims to propose mechanisms to aid DMUC synchronization. Before that, we show that existing tools cannot be directly adapted to AEC sector. To do so, this thesis focuses on tracking changes within a DMUC during design process, thanks to comparison of structured information (structural information). We consider also the meaning of used concepts (semantic comparison). This analysis is done at the meta-model level (EXPRESS language) instead of a specific data model (IFC, IFC-BRIDGE). This generic approach guarantees some robustness for future evolutions of DMUC. From a configuration based on a structural helper (only a few lines of XML code), the software engineer automatically generates a library of structural comparison, adapted to the application data model. Semantic analysis makes the system very flexible : partial extract of information, definition of semantic equivalences and tolerance on numerical values. Designed system does not depend on any data persistence tool. Besides, extraction of information is carried out without any model mapping. C++ implementation of structural and semantic comparison uses tools of automatic generation of source code. Last this work provides several perspectives when they are associated to predictive and reactive design activities.La Maquette Numérique (MN) est une représentation numérique, centralisée et hiérarchisée de l'ensemble des productions des acteurs au cours d'un projet. Dans le cadre du secteur BTP, la Maquette Numérique de Construction (MNC) constitue l'adaptation de la technologie précédente à ce secteur. Cependant, la conception en génie civil semble se distinguer de celle des produits manufacturés, notamment à cause de la multiplicité et l'hétérogénéité des acteurs, mais aussi de la création d'un ouvrage unique. Par conséquent, les processus en jeu durant cette phase nécessitent une analyse particulière. Notre travail consiste donc à proposer des mécanismes d'aide à la synchronisation de la MNC, après avoir montré que les outils existants, adaptés à la conception de produits manufacturés, ne peuvent être directement transposés au secteur du BTP. Pour cela, cette thèse se focalise sur le suivi des modifications de la MNC en cours de conception, par l'intermédiaire de comparaisons d'information structurées (comparaisons dites structurelles), tout en prenant en compte la signification des concepts utilisés (comparaisons sémantiques). L'analyse a été portée au niveau du méta-modèle (langage EXPRESS) plutôt que le modèle de données lui-même (IFC, IFC-Bridge, etc.). Cette généricité assure une robustesse face aux évolutions futures des MNC. A partir d'une configuration sur la base d'un assistant structurel (seulement quelques lignes de code XML), le constructeur d'application génère automatiquement une bibliothèque de comparaison structurelle, adaptée au modèle de données métiers. L'analyse sémantique rend, quant à elle, le système très flexible : possibilité d'extraire partiellement l'information, définition d'équivalents sémantiques et de tolérances de valeurs numériques. Le système conçu ne dépend d'aucun outil de persistance des données. De plus, l'extraction d'information s'effectue sans transformation de modèles. L'implémentation, en C++, de la comparaison structurelle et sémantique utilise des outils de génération automatique de code source. Enfin, ces travaux apportent de nombreuses perspectives s'ils sont liés aux activités prédictives et réactives de conception

Feeding Milking Shorthorn Steers

The objectives of the feeding work were to provide the producer with feed-lot data and where possible with slaughter data for Milking Shorthorn steers. As a definite breeding research program with the Milking Shorthorn herd was planned, it also was believed that information about the beef-making qualities of the steers should be of equal importance with milk and butterfat production records

Feeder pig grading standards

1 online resource (PDF, 2 pages)This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu