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Hennings, Peter H., Jens‐Erik Lund Snee, Johnathon L. Osmond, Heather R. DeShon, Robin Dommisse, Elizabeth Horne, Casee Lemons, and Mark D. Zoback. "Injection‐Induced Seismicity and Fault‐Slip Potential in the Fort Worth Basin, Texas." Bulletin of the Seismological Society of America 109, no. 5 (July 23, 2019): 1615–34. http://dx.doi.org/10.1785/0120190017.
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Abstract The rate of seismicity in the hydrocarbon‐producing Fort Worth Basin of north‐central Texas, which underlies the Dallas–Fort Worth metropolitan area, increased markedly from 2008 through 2015, coinciding spatiotemporally with injection of 2 billion barrels of wastewater into deep aquifers. Although the rate of seismicity has declined with injection rates, some earthquake sequences remained active in 2018 and new clusters have developed. Most of this seismicity occurred away from regionally mapped faults, challenging efforts to constrain the continuing hazards of injection‐induced seismicity in the basin. Here, we present detailed new models of potentially seismogenic faults and the stress field, which we use to build a probabilistic assessment of fault‐slip potential. Our new fault map, based on reflection seismic data, tens of thousands of well logs, and outcrop characterization, includes 251 basement‐rooted normal faults that strike dominantly north‐northeast, several of which extend under populated areas. The updated stress map indicates a relatively consistent north‐northeast–south‐southwest azimuth of the maximum horizontal principal stress over seismically active parts of the basin, with a transition from strike‐slip faulting in the north to normal faulting in the southeast. Based on these new data, our probabilistic analysis shows that a majority of the total trace length of the mapped faults have slip potential that is equal to or higher than that of the faults that have already hosted injection‐induced earthquake sequences. We conclude that most faults in the system are highly sensitive to reactivation, and we postulate that many faults are still unidentified. Ongoing injection operations in the region should be conducted with these understandings in mind.
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Brunet, Louis. "RÉFLEXION SUR TROIS POINTS DE DÉONTOLOGIE." Revue québécoise de psychologie 39, no. 3 (March 21, 2019): 223–33. http://dx.doi.org/10.7202/1058191ar.
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La déontologie est un ensemble de règles qui doivent être interprétées à la lumière de principes éthiques et de principes cliniques. Il existe actuellement dans la pratique psychologique au Québec une série de règles déontologiques qui font l’objet d’interprétations fort diverses et même contradictoires. Le texte propose d’analyser trois de ces problèmes d’interprétation, en proposant ce qui nous semble être des interprétations qui respectent à la fois l’éthique et les grands principes cliniques, tout en espérant susciter un sain débat sur ces questions.
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Bonafede, Salvatore, and Francesco Nicolosi. "A generalized maximum principle for boundary value problems for degenerate parabolic operators with discontinuous coefficients." Mathematica Bohemica 125, no. 1 (2000): 39–54. http://dx.doi.org/10.21136/mb.2000.126266.
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Takáč, Peter. "An Abstract Form of Maximum and Anti-maximum Principles of Hopf's Type." Journal of Mathematical Analysis and Applications 201, no. 2 (July 1996): 339–64. http://dx.doi.org/10.1006/jmaa.1996.0259.
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Colas, Émile. "Les caractéristiques originales des coopératives en droit québécois." Revue générale de droit 16, no. 2 (May 2, 2019): 223–72. http://dx.doi.org/10.7202/1059294ar.
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Les règles d’action coopératives édictées à l’article 4 de la nouvelle Loi sur les coopératives du Québec donnent le ton et représentent l’enveloppe juridique d’une pensée originale beaucoup plus large. Les principes sociaux de la libre adhésion, de la gestion démocratique, de la promotion de la coopération, de l’éducation coopérative et du fédéralisme coopératif sont complétés par l’étude des éléments distinctifs d’ordre économique de la double qualité entrepreneur-client, du capital variable, de l’intérêt limité, de l’emploi des trop-perçus ou excédents d’exploitation et enfin de la vente et l’achat au comptant. Il s’agit de principes fort louables du point de vue idéologique mais certaines dispositions légales et plusieurs problèmes d’ordre technico-pratique ont quelque peu amoindri le particularisme et la valeur théorique des principes en cause.
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Bonafede, Salvatore. "A weak maximum principle and estimates of ${\rm ess}\sup\sb \Omega u$ for nonlinear degenerate elliptic equations." Czechoslovak Mathematical Journal 46, no. 2 (1996): 259–69. http://dx.doi.org/10.21136/cmj.1996.127289.
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ROBERT-GRANIÉ, C., A. LEGARRA, and V. DUCROCQ. "Principes de base de la sélection génomique." INRAE Productions Animales 24, no. 4 (September 8, 2011): 331–40. http://dx.doi.org/10.20870/productions-animales.2011.24.4.3265.
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Avec l’arrivée de données de génotypage à haut débit, il est maintenant possible d’estimer la valeur génétique d’animaux candidatsà la sélection dès leur naissance, sans attendre la collecte de phénotypes. La sélection génomique bouleverse complètement les perspectivesen amélioration génétique. Elle nécessite la constitution d’une population de référence formée d’animaux génotypés (jusqu’àrécemment, il s’agissait principalement de mâles) et ayant des performances précises, par exemple la performance moyenne de leursfilles. Les évaluations génomiques consistent à prédire les phénotypes dans cette population de référence comme la somme des effetsdes marqueurs moléculaires. Le problème méthodologique principal est que le nombre d’effets à estimer est typiquement beaucoupplus élevé que le nombre de phénotypes disponibles. Nous décrivons les idées générales de diverses familles de méthodes proposées :BLUP génomique basé sur une parenté entre individus calculée à partir des marqueurs, méthodes Bayésiennes plus flexibles maisaussi plus coûteuses, méthodes de sélection de variables, méthode en une seule étape qui combine évaluation génétique nationale etévaluation génomique. La précision des évaluations génomiques est faite par validation croisée chez les animaux les plus jeunes de lapopulation de référence. La taille de la population de référence, la manière de prendre en compte les QTL à effet fort et le degré d’apparentemententre candidats à la sélection et animaux de la population de référence ont un impact non négligeable sur l’efficacité desméthodes de sélection génomique.
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Al-Mahamee, Mohammad. "Maximum Principles for Second Order Elliptic Equations in Nondivergence Form and Applications." Journal of Mathematics and Statistics 4, no. 1 (January 1, 2008): 9–14. http://dx.doi.org/10.3844/jmssp.2008.9.14.
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Niderst, Alain. "Le monde de Fontenelle." Images et imaginaire de l’espace 34, no. 1-2 (February 23, 2004): 241–48. http://dx.doi.org/10.7202/007565ar.
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Résumé L’espace de Fontenelle est d’abord un espace cosmique. Trois principes l’organisent : l’empirisme, hérité de la scolastique, l’éternité et la divisibilité de la matière, l’assimilation de l’univers à une machine, dont le mouvement a été donné et est surveillé par Dieu. Fontenelle, dans les Pastorales et dans ses opéras, est un poète du ciel et du mouvement des planètes. Cette splendeur se ramène aux grands principes que nous avons mis en évidence et surtout au mécanisme et aux tourbillons cartésiens. Ainsi l’univers est comparable à une montre. Il y a la beauté d’une scène d’opéra et l’éclat d’une « feuille d’or ». Mais le philosophe enlève la feuille et discerne dans les merveilles théâtrales le jeu des poids et des contrepoids. Ce serait triste : la littérature pare le mécanisme, comme Dieu le cache sous les beautés de la nature. Il en est de même en morale : notre vie serait fort triste sans les plaisirs qui l’animent.
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Morin, Michel. "Fraternité, souveraineté et autonomie des Autochtones en Nouvelle-France." Dossier : La parenté et les traités 43, no. 2 (February 27, 2014): 531–98. http://dx.doi.org/10.7202/1023206ar.
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Aux xviie et xviiie siècles, les principes juridiques encadrant les relations entre les Algonquiens de la vallée du Saint-Laurent et les Français sont généralement bien compris par chacune des parties en présence. Initialement fondés sur les concepts d’amitié, d’alliance ou de fraternité, ces principes postulent l’existence de nations indépendantes possédant leurs propres structures décisionnelles et leurs coutumes, ainsi que de chefs locaux ou régionaux qui jouissent en pratique d’une grande autorité. De 1628 à 1663, le statut de sujet du roi de France est d’ailleurs accordé uniquement aux nouveaux convertis, puis, de 1664 à 1674, à leurs descendants. Par la suite, la situation est ambiguë. Toutefois, les communautés de chrétiens vivant près des villes françaises conservent une grande autonomie à laquelle elles acceptent rarement de renoncer. Elles sont parfois qualifiées d’enfants du roi, parce qu’elles soutiennent inconditionnellement les Français sur le plan militaire. Dans la deuxième moitié du xviie siècle, des nations non converties reconnaissent également le statut de père au roi de France, mais cette dépendance socio-économique et militaire ne remet pas en question leur indépendance, ce que les Français comprennent fort bien.
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Lebrun, Johanne, Yves Lenoir, and Julie Desjardins. "Le manuel scolaire « réformé » ou le danger de l’illusion du changement : analyse de l’évolution des critères d’évaluation des manuels scolaires de l’enseignement primaire entre 1979 et 2001." Revue des sciences de l'éducation 30, no. 3 (January 18, 2006): 509–33. http://dx.doi.org/10.7202/012080ar.
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RésuméCet article analyse, en les comparant à ceux qui prévalaient antérieurement, les nouveaux critères qui président à l’évaluation des manuels scolaires qui ont été édictés en 2001 par le ministère de l’Éducation du Québec. Les résultats révèlent que les critères ont été fort peu modifiés, si ce n’est qu’en surface. Force est de conclure que les nouveaux critères maintiennent la logique de transmission et de substitution dévolue aux manuels scolaires depuis 1979. Conséquemment, on ne peut que constater que le ministère reconduit les principes précédemment en vigueur d’une évaluation qui risque de demeurer superficielle et peu articulée. L’adéquation des futurs manuels pour la mise en oeuvre d’une intervention éducative s’inscrivant dans une perspective constructiviste est dès lors compromise.
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Konôpka, Bohdan, Jozef Pajtík, Michal Bošeľa, Tomáš Hlásny, and Zuzana Sitková. "Inter- and intra-annual dynamics of height increment in young beech and spruce stands in relation to tree size and weather conditions." Forestry Journal 60, no. 1 (March 1, 2014): 52–60. http://dx.doi.org/10.2478/forj-2014-0005.
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Abstract We investigated the seasonal dynamics of height increment, as well as total annual height increment, in 2009-2013 on young stands of beech and spruce grown at the same site. The results showed that the inter-annual dynamics of basic stand characteristics, especially tree density, were more obvious in spruce than in beech stands. Much higher tree mortality in spruce was explained by a lower light intensity under the spruce stand canopy and higher tolerance of beech to shade. Large interspecific differences were also found in the timing of height increment. Specifically, the height increment of beech trees started earlier than those of spruce. Moreover, the terminal grew for longer in spruce (nearly 70 days) compared to beech (about 45 days). The comparisons between the courses of the height increment and the ambient factors suggested that global radiation played a principal role. In the beech stand, the maximum height increment rate occurred during the same days as the maximal global radiation in 2009 and 2011, while a decline of the height increment occurred simultaneously with a depression in global radiation in 2012. As for the spruce stand, its one-peak maxima in height increment were related to the maximum of global radiation in 2009 and in 2012. On the other hand, double-peak courses of height increment in 2010 and 2011 may have been related to sudden declines in global radiation. Interspecific differences in height increment timing might play a certain role in cases of unfavourable weather conditions, e.g. drought episodes in the middle part of the growing season when the height increment would be accomplished in beech but would still be ongoing in spruce.
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Naick, Bhukya Krishna, Tarun Kumar Chatterjee, and Kalyan Chatterjee. "Performance Analysis of Maximum Power Point Tracking Algorithms Under Varying Irradiation." International Journal of Renewable Energy Development 6, no. 1 (March 22, 2017): 65–74. http://dx.doi.org/10.14710/ijred.6.1.65-74.
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Photovoltaic (PV) system is one of the reliable alternative sources of energy and its contribution in energy sector is growing rapidly. The performance of PV system depends upon the solar insolation, which will be varying throughout the day, season and year. The biggest challenge is to obtain the maximum power from PV array at varying insolation levels. The maximum power point tracking (MPPT) controller, in association with tracking algorithm will act as a principal element in driving the PV system at maximum power point (MPP). In this paper, the simulation model has been developed and the results were compared for perturb and observe, incremental conductance, extremum seeking control and fuzzy logic controller based MPPT algorithms at different irradiation levels on a 10 KW PV array. The results obtained were analysed in terms of convergence rate and their efficiency to track the MPP.Article History: Received 3rd Oct 2016; Received in revised form 6th January 2017; Accepted 10th February 2017; Available onlineHow to Cite This Article: Naick, B. K., Chatterjee, T. K. & Chatterjee, K. (2017) Performance Analysis of Maximum Power Point Tracking Algorithms Under Varying Irradiation. Int Journal of Renewable Energy Development, 6(1), 65-74.http://dx.doi.org/10.14710/ijred.6.1.65-74
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Faragó, István, Sergey Korotov, and Tamás Szabó. "On Modifications of Continuous and Discrete Maximum Principles for Reaction-Diffusion Problems." Advances in Applied Mathematics and Mechanics 3, no. 1 (February 2011): 109–20. http://dx.doi.org/10.4208/aamm.10-m1027.
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AbstractIn this work, we present and discuss some modifications, in the form of two-sided estimation (and also for arbitrary source functions instead of usual sign-conditions), of continuous and discrete maximum principles for the reactiondiffusion problems solved by the finite element and finite difference methods.
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Tirel, Astrid. "L’analyse dramaturgique autochtone comme nouvel objet de la sociologie." Cahiers de recherche sociologique, no. 59-60 (June 15, 2016): 245–57. http://dx.doi.org/10.7202/1036796ar.
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Si la sociologie peut faire son objet de tout phénomène social, elle ne peut faire abstraction des changements d’appréhension, de perception et de représentation qui interviennent entre les acteurs concernés. Or la dramaturgie autochtone nécessite un décentrement du regard pour apprécier un modèle esthétique qui, s’il s’inscrit fort bien dans les schèmes occidentaux du genre, propose une esthétique ancrée dans des savoirs culturels dont les principes et valeurs lui échappent. À ce titre, l’étude de cette dramaturgie se situe au confluent de diverses disciplines telles que les études sociologiques, anthropologiques, politiques, théâtrales, post-culturelles ou théologiques qu’elle mobilise. En bousculant la légitimité du savoir, elle exige de nouveaux outils méthodologiques susceptibles de rendre compte des réalités contemporaines de la diversité et de leur impact sur la vie en société.
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Landry, Simone. "Les femmes et la qualité totale." L’actualité 6, no. 1 (January 22, 2008): 173–83. http://dx.doi.org/10.7202/301207ar.
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Résumé La récession économique a donné aux nouvelles formes d'organisation du travail, dont l'approche de la qualité totale, l'allure de remèdes magiques susceptibles de permettre la survie d'entreprises au bord de la faillite. Les syndicats se doivent d'analyser ces nouvelles approches et de se positionner par rapport à elles. Mais il ne faut pas oublier qu'il s'agit là d'abord et avant tout de statégies de gestion, c'est-à-dire de stratégies patronales. Par ailleurs, les principes qui sous-tendent l'approche de la qualité totale rejoignent par plusieurs aspects des valeurs généralement associées à la culture des femmes. Certaines de ces valeurs sont ici décrites et les femmes sont invitées à la prudence face à cette nouvelle approche qui pourrait fort bien surcharger encore davantage la super-femme d'aujourd'hui.
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Dermine-Brullot, Sabrina, and André Torre. "Dossier « L’économie circulaire : modes de gouvernance et développement territorial » – Quelle durabilité pour le développement territorial ? Réflexions sur les composantes spatiales de l’économie circulaire." Natures Sciences Sociétés 28, no. 2 (April 2020): 108–17. http://dx.doi.org/10.1051/nss/2020034.
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L’objectif de cet article est de fournir des éléments de réflexion sur la place de l’espace et la dimension territoriale dans les processus d’économie circulaire ainsi que d’interroger leur contribution au développement durable des territoires. Nous commençons par examiner les racines territoriales des grandes stratégies d’économie circulaire définies par les pouvoirs publics français en faisant une place particulière à l’écologie industrielle et territoriale, qui manifeste un intérêt plus fort pour les dimensions spatiales des processus circulaires. Dans une seconde partie, nous interrogeons la capacité réelle de l’économie circulaire à contribuer au développement durable de la société dans son ensemble et à sa mise en action au niveau local : après avoir proposé une définition du développement territorial durable, nous procédons à un examen des différentes stratégies en cours fondées sur les principes ainsi définis.
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Mendola, Joseph. "Intuitive Maximin." Canadian Journal of Philosophy 35, no. 3 (September 2005): 429–39. http://dx.doi.org/10.1080/00455091.2005.10716597.
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One standard objection to familiar utilitarian consequentialism queries its troubling commitment to the maximization of overall value irrespective of distribution, for instance among the well and badly off. Call this ‘the objection from distribution.'The simplest and most obvious alternative form of consequentialism deploys some sort of maximin principle. Maximin principles maximize the well-being of the worst off. Lexical maximin rules in particular, which are perhaps the simplest and most obvious subtype, maximize first the well-being of the worst-off, and then in case of ties among the worst-off, maximize the well-being of the second worst-off, and so forth. Maximin principles provide an obvious route to the unification of plausible concerns with maximization and with distributional equity.
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Enache, Cristian. "Maximum principles for a class of nonlinear second-order elliptic boundary value problems in divergence form." Boundary Value Problems 2006 (2006): 1–13. http://dx.doi.org/10.1155/bvp/2006/64543.
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Guitard, Paulette. "L'apprentissage expérientiel et l'ergothérapie: Compatibilité théorique et pratique." Canadian Journal of Occupational Therapy 63, no. 4 (October 1996): 252–59. http://dx.doi.org/10.1177/000841749606300406.
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Pour favoriser l'adaptation du client, l'ergothérapeute doit souvent avoir recours à l'enseignement. La relation ergothérapeute-client est alors modifiée et définie comme le processus enseignement-apprentissage. L'ergothérapie reconnaît le processus enseignement-apprentissage comme un outil d'intervention fort précieux, mais il demeure néanmoins méconnu des ergothérapeutes. La littérature mentionne peu de modèles éducatifs ou pédagogiques utilisés en ergothérapie. Un des modèles cités est celui de l'apprentissage expérientiel. Ce modèle est un processus cyclique qui se base sur l'activité, l'expérience concrète de l'apprenant pour favoriser l'apprentissage. L'apprentissage est alors plus significatif pour l'apprenant et mieux intégré à sa réalité quotidienne. Le présent article définit ce modèle d'apprentissage et présente une analyse comparative de ses principes de base et des croyances fondamentales de l'ergothérapie. L'analyse démontre que l'approche expérientielle est tout à fait compatible avec la philosophie et la pratique de l'ergothérapie.
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Marandola, Fabrice. "Dossier enquête : Pulau Dewata : des arrangements raisonnables ?" Circuit 18, no. 3 (October 16, 2008): 53–72. http://dx.doi.org/10.7202/019139ar.
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Résumé Pulau Dewata est la seule oeuvre de Claude Vivier dont l’orchestration reste totalement libre. Composée en 1977, au retour d’un voyage consacré pour une large part à l’étude de la musique balinaise, elle a fait depuis l’objet d’un nombre conséquent d’adaptations fort diverses qui vont de la stricte répartition instrumentale du matériau musical original à l’orchestration la plus élaborée. Afin de comprendre pourquoi les « arrangements » des uns apparaissent comme des « dérangements » pour les autres, l’article procède à une mise en perspective des orchestrations qui en ont été réalisées, avec des exemples provenant principalement des versions de John Rea et Walter Boudreau. Cette comparaison des approches est précédée d’une analyse de la forme et des principes qui ont guidé la composition de Pulau Dewata, analyse qui s’appuie notamment sur les esquisses et les notes de travail du compositeur conservées aux archives de l’Université de Montréal.
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Aprilliani, Fasha Nabilah, Muhammad Rohmadi, and Atikah Anindyarini. "PELANGGARAN PRINSIP KERJA SAMA DALAM PEMBELAJARAN BAHASA INDONESIA DI SMK BATIK 1 SURAKARTA." Basastra: Jurnal Bahasa, Sastra, dan Pengajarannya 6, no. 2 (December 6, 2019): 61. http://dx.doi.org/10.20961/basastra.v6i2.37674.
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<em>The purpose of this research is to explain and describe (1) a form of violation of the principle of cooperation in the interaction of learning Indonesian in SMK Batik 1 Surakarta; (2) the purpose of violating the principle of cooperation in learning Indonesian in SMK Batik 1 Surakarta; (3) the function of violating the principle of cooperation in the interaction of learning Indonesian in SMK Batik 1 Surakarta. This research is descriptive qualitative research with main data source that is recording of learning activity of Indonesia in class X Visual Communication Design and XI Marketing. Technique of data retrieval in this research use observation technique and deep interview technique. Technique of taking research subject using purposive sampling technique. The data validity test used is triangulation technique and triangulation theory. Data analysis techniques using interactive analysis techniques. Based on the results of the research, found a speech breaking a maximum of cooperation and speech principles that violate two maxims of cooperation principles, called a single maximal offense and a double maximal offense. Violation of maxim that happened not only done by teacher but also done by student. Maximum violations have 11 violation objectives. Maximum violation of the principle of cooperation done by both students and teachers have their respective functions. The function of language related to maximal violation have 7 functions.</em>
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Winguth, A. M. E., and B. Kelp. "The Urban Heat Island of the North-Central Texas Region and Its Relation to the 2011 Severe Texas Drought." Journal of Applied Meteorology and Climatology 52, no. 11 (November 2013): 2418–33. http://dx.doi.org/10.1175/jamc-d-12-0195.1.
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AbstractHourly surface temperature differences between Dallas–Fort Worth, Texas, metropolitan and rural sites have been used to calculate the urban heat island from 2001 to 2011. The heat island peaked after sunset and was particularly strong during the drought and heat wave in July 2011, reaching a single-day instantaneous maximum value of 5.4°C and a monthly mean maximum of 3.4°C, as compared with the 2001–11 July average of 2.4°C. This severe drought caused faster warming of rural locations relative to the metropolitan area in the morning as a result of lower soil moisture content, which led to an average negative heat island in July 2011 of −2.3°C at 1100 central standard time. The ground-based assessment of canopy air temperature at screening level has been supported by a remotely sensed surface estimate from the Moderate Resolution Imaging Spectroradiometer (MODIS) on board the Terra satellite, highlighting a dual-peak maximum heat island in the major city centers of Dallas and Fort Worth. Both ground-based and remotely sensed spatial analyses of the maximum heat island indicate a northwest shift, the result of southeast winds in July 2011 of ~2 m s−1 on average. There was an overall positive trend in the urban heat island of 0.14°C decade−1 in the Dallas–Fort Worth metropolitan area from 2001 to 2011, due to rapid urbanization. Superimposed on this trend are significant interannual and decadal variations that influence the urban climate.
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Jullien, Vincent. "Relativité, determinatio et parallaxe, remarques sur le traitement cartésien de trois controverses scientifiques." Articles 38, no. 2 (January 11, 2012): 493–521. http://dx.doi.org/10.7202/1007461ar.
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Trois sujets de philosophie naturelle, fort controversés à l’époque où Descartes élabore sa physique (incluant son système du Monde) sont particulièrement présents dans les Principes de la philosophie de Descartes, le principe de relativité des mouvements des corps matériels, la nature que l’on nommera plus tard vectorielle de la grandeur, qui caractérise l’état de mouvement d’un corps et que Descartes contribue à constituer par la notion de determinatio et l’objection parallactique contre l’héliocentrisme. On examine ici comment l’actualité du débat scientifique permet de comprendre l’argumentation cartésienne et on insiste sur le caractère polémique de ce traité. On peut notamment relever que les théories galiléennes pèsent d’un grand poids dans la modification des conceptions cartésiennes du mouvement et que les arguments, alors les plus récents, avancés en astronomie soutiennent la mise au point du système du monde cartésien. Il s’agit de mettre l’histoire des sciences au service d’une meilleure intelligence de la somme philosophique cartésienne.
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Pineau, Jean. "Les grands objectifs et les lignes de force de la réforme." La réforme du droit des obligations 30, no. 3 (April 12, 2005): 587–97. http://dx.doi.org/10.7202/042964ar.
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On reproche au Code civil du Bas-Canada de reposer essentiellement sur une théorie de l'autonomie de la volonté qui permettrait au fort d'écraser le faible et sur une théorie de la responsabilité fondée sur la faute, qui laisse la victime sans indemnisation lorsque le préjudice ne résulte pas d'un comportement fautif de l'auteur. Pour remédier à certaines injustices, le législateur eut recours à l'adoption de règles particulières, souvent imperatives. Que peut-on faire à l'aube d'un nouveau code, pour tenter de mieux équilibrer les rapports individuels ? De l'Avant-projet, semblent se dégager deux lignes de force : d'une part, la consolidation de la théorie générale, par la codification de principes déjà reconnus et par la mise en relief d'armes inexploitées ou explicitées; d'autre part, l'accentuation de l'esprit protectionniste dans les contrats nommés. Jusqu'où le législateur peut-il aller dans le désir de protéger certaines catégories de personnes et comment peut-il y parvenir ?
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Mosquera, Dolores, Andrew M. Leeds, and Anabel Gonzalez. "Application de la thérapie EMDR au trouble de la personnalité borderline." Journal of EMDR Practice and Research 9, no. 4 (2015): 123E—141E. http://dx.doi.org/10.1891/1933-3196.9.4.123.
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Il y a aujourd'hui un intérêt croissant pour l'utilisation de la thérapie de désensibilisation et de retraitement par les mouvements oculaires (EMDR), au-delà du traitement de l'état de stress post-traumatique (ESPT) où son application est bien établie. Étant donné le fort consensus scientifique actuel autour de la responsabilité des vécus traumatiques du passé dans le développement d'un trouble de la personnalité borderline (TPB), l'EMDR semble en effet pouvoir apporter beaucoup au traitement des personnes qui en souffrent. Cependant, les traits spécifiques de ces patients font que l'application de la thérapie EMDR dans leur traitement s'avérer parfois difficile et nécessite plusieurs adaptations (mineures) des procédures standard de l'EMDR pour l'ESPT. Le présent article propose des principes et des stratégies permettant de préparer de façon sûre et efficace les patients TPB à la thérapie EMDR et d'accéder et de retraiter les origines traumatiques du TPB. Des exemples cliniques sont donnés tout au long de cet article.
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Nicolas, Patrice. "De quelques fausses idées du contrepoint d’école et de leurs conséquences." Les Cahiers de la Société québécoise de recherche en musique 14, no. 2 (March 13, 2014): 11–24. http://dx.doi.org/10.7202/1023737ar.
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Désirant renouer avec une tradition contrapuntique dont les principes étaient depuis longtemps oubliés, les théoriciens de l’école française des xixe et xxe siècles, désormais dominés par les notions harmoniques, donnèrent les chimères de leur imagination pour des vérités ayant de tout temps existé. Il est donc malheureux que leurs ouvrages servent encore de base à l’enseignement du contrepoint dans la plupart des institutions québécoises d’éducation musicale, en ce qu’ils condamnent l’esprit de tout apprenti contrapuntiste à se perdre dans le dédale inextricable d’une science imaginaire. Il en résulte d’ailleurs un fait fort inquiétant sur lequel on ne peut plus élever le moindre doute : c’est que le contrepoint d’école ne mène aucunement l’étudiant vers les grands polyphonistes. Dès lors, incapable d’analyser correctement les oeuvres du Moyen Âge et de la Renaissance – et donc incapable d’en saisir les mécanismes et de s’en faire une idée complète –, l’apprenti compositeur s’en détourne, passant à côté de bien des techniques d’écritures fort intéressantes, lesquelles, surtout en ces temps postmodernes, ne pourraient donner que plus d’élan à son originalité. Après un bref exposé de la théorie contrapuntique originelle, quelques-unes des fictions romantiques sont passées en revue. Il est ainsi démontré que rien ne vaut l’emploi des traités du Moyen Âge et de la Renaissance pour l’enseignement du contrepoint et de l’analyse de la musique ancienne. De courts extraits tirés d’oeuvres de différentes époques sont analysés afin de montrer que la théorie contrapuntique originelle conduit à une parfaite compréhension des oeuvres contemporaines, une chose à laquelle ne peut prétendre le pseudo-contrepoint romantique.
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Carnis, Laurent. "Le contrôle automatisé de la vitesse en Australie : quelques enseignements pour mener une politique de dissuasion efficace." Criminologie 41, no. 2 (November 26, 2008): 269–90. http://dx.doi.org/10.7202/019440ar.
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Résumé Le contrôle automatisé de la vitesse (CAV) constitue une modalité d’intervention des autorités pour réduire le nombre de victimes de la route. Cette technique de détection permet d’accroître l’intensité des contrôles, d’augmenter la sanction potentielle des contrevenants et de rendre possible une procédure judiciaire plus rapide. Ce type de dispositif a été introduit pour la première fois en Australie au milieu des années 1980 dans l’État de Victoria. Depuis, cette technique s’est généralisée à l’ensemble des États. Les dispositifs en fonctionnement se révèlent fort divers et s’appuient sur des stratégies spécifiques. Néanmoins, ces expériences convergent vers une même conclusion : la diminution significative des accidents de la circulation et le nombre de victimes. Ils s’avèrent donc particulièrement efficaces. Par ailleurs, ces différents programmes de contrôle s’appuient sur des architectures organisationnelles et institutionnelles différentes, illustrant par la même une certaine souplesse quant à leur implantation dans des environnements particuliers. Toutefois, ils reposent tous sur les principes simples des « 4C » (contrôle, coopération, communication et continuité), nécessitant l’intégration des acteurs clés.
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Ndogmo, Jean-Claude. "Some variational principles associated with ODEs of maximal symmetry. Part 1: Equations in canonical form." Journal of Applied Analysis 24, no. 1 (June 1, 2018): 17–26. http://dx.doi.org/10.1515/jaa-2018-0002.
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AbstractVariational and divergence symmetries are studied in this paper for linear equations of maximal symmetry in canonical form, and the associated first integrals are given in explicit form. All the main results obtained are formulated as theorems or conjectures for equations of a general order. Some of these results apply to linear equations of a general form and of arbitrary orders or having a symmetry algebra of arbitrary dimension.
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Estwick, Stacey Alicia. "The impact of principal-principal conflict on financial flexibility." Qualitative Research in Financial Markets 8, no. 4 (November 7, 2016): 305–30. http://dx.doi.org/10.1108/qrfm-12-2015-0043.
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Purpose This study examined the attainment and the benefits of financial flexibility in the presence of concentrated ownership in the Caribbean. Design/methodology/approach This study used qualitative methodology via the use of case studies. Findings Results revealed that liquidity may be considered the most important form of financial flexibility for firms in transitioning economies, due to constrained capital markets. Blockholder firms also focus on liquidity out of a concern for recovering their substantial investment. This study suggested that in addition to an emphasis on liquidity, blockholder owners emphasise professionalism in managing the firm. This professionalism, accompanied by a genuine separation of ownership and control, may be critical in minimising the possibility of misappropriation of surplus liquidity. The study showed that blockholder owned firms may not recognise maximum capital investment benefits because of the use of sub-optimal capital budgeting techniques reflecting their liquidity preference, or pay maximum dividends, opting instead to use dividends as a governance tool. However, the ability to separate ownership from the management of the operations may counteract this, leading to an increased focus on net present value (NPV) maximising projects, and a dividend policy aimed at preserving future financial flexibility. Research limitations/implications This study highlights the value of qualitative studies in finance research, by providing a deeper insight into the management of firm financial flexibility, under blockholder ownership. It emphasises the importance of considering liquidity as a critical form of financial flexibility. Furthermore, the study shows that two significant factors in controlling principal–principal (PP) conflict may be the ability to separate ownership from control and the appointment of a professional management team. Originality/value This research introduces the variable of PP agency in the study of financial flexibility.
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Huscroft, Crystal A., Brent C. Ward, René W. Barendregt, Lionel E. Jackson Jr., and Neil D. Opdyke. "Pleistocene volcanic damming of Yukon River and the maximum age of the Reid Glaciation, west-central Yukon." Canadian Journal of Earth Sciences 41, no. 2 (February 1, 2004): 151–64. http://dx.doi.org/10.1139/e03-098.
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Stratigraphic, paleomagnetic, and radioisotope investigations of the Selkirk Volcanic Group have identified a new eruptive period and constrained the age of the Reid Glaciation, the most extensive middle Pleistocene cordilleran advance recognized in central Yukon. Downstream from Fort Selkirk, a complex of valley-filling compound pahoehoe basalt flows and pillow basalt is exposed for 10 km along the Yukon River and is overlain by outwash deposited during the Reid Glaciation. The flows have an 40Ar/39Ar age of 311 ± 32 ka. This age is consistent with the normal magnetization of the flows and their termination below the level of the contemporary Yukon River flood plain. Taken with the ca. 190 ka Sheep Creek tephra, which overlies Reid drift elsewhere in Yukon Territory, the Reid Glaciation is constrained to oxygen isotope stage 8, not stage 6 as previously thought. The presence of thick foreset-bedded pillow breccia units intercalated with the subaerial flows indicates that this eruption caused damming of the Yukon River. Reevaluation of the stratigraphy of early Pleistocene basalt flows and pillow lavas in the Fort Selkirk area indicates that volcanic damming of the Yukon River has occurred at least once previously.
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Caloz, R., A. Pointet, and C. Collet. "Approche comparée de méthodes de classification d'images aériennes : une étude de cas." Geographica Helvetica 58, no. 2 (June 30, 2003): 141–53. http://dx.doi.org/10.5194/gh-58-141-2003.
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Abstract. L'exploitation d'images aériennes ou satellitales à très haute résolution (< 5 m) remet en cause des procédures de Classification qui pourtant avaient fait leur preuve pour l'exploitation d'images à plus faible résolution. Par une étude de cas portant sur les dégâts forestiers provoqués par le passage de l'ouragan Lothar en fin décembre 1999, nous mettons en évidence le comportement de deux approches, l'une conventionnelle basée sur une Classification non-dirigée, l'autre exploitant la notion de croissance de région. Ces méthodes numériques sont mises en relation avec une cartographie des dégâts réalisée par photointerprétation. On montre que photointerprétation et approche numérique ne peuvent être comparées en termes strictement quantitatifs du fait de règles différentes intervenant dans la généralisation des contours des unités spatiales. Un bref résumé des principes sur lesquels est construite la Classification par croissance de région est présenté. L'image aérienne utilisée présentant un fort effet de «hot spot», il a été possible de mettre en évidence une plus grande robustesse des signatures définies par catégorie thématique dans le cas de la classification par croissance de région. Les zones de dègâts sont déterminées avec le même taux de réussite, indépendamment de leur position dans l'image.
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Cocchetti, Giuseppe, and Egidio Rizzi. "Least-thickness symmetric circular masonry arch of maximum horizontal thrust." Archive of Applied Mechanics 91, no. 6 (March 20, 2021): 2617–39. http://dx.doi.org/10.1007/s00419-021-01909-1.
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AbstractThis analytical note shall provide a contribution to the understanding of general principles in the Mechanics of (symmetric circular) masonry arches. Within a mainstream of previous research work by the authors (and competent framing in the dedicated literature), devoted to investigate the classical structural optimization problem leading to the least-thickness condition under self-weight (“Couplet-Heyman problem”), and the relevant characteristics of the purely rotational five-hinge collapse mode, new and complementary information is here analytically derived. Peculiar extremal conditions are explicitly inspected, as those leading to the maximum intrinsic non-dimensional horizontal thrust and to the foremost wide angular inner-hinge position from the crown, both occurring for specific instances of over-complete (horseshoe) arches. The whole is obtained, and confronted, for three typical solution cases, i.e., Heyman, “CCR” and Milankovitch instances, all together, by full closed-form explicit representations, and elucidated by relevant illustrations.
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Murphy, John M., and Arne Bakke. "Low-temperature thermal history of the Gilmore Dome area, Fairbanks Mining District, Alaska." Canadian Journal of Earth Sciences 30, no. 4 (April 1, 1993): 764–68. http://dx.doi.org/10.1139/e93-062.
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Eight apatite and two zircon fission-track ages provide evidence of complex Tertiary thermal overprinting by hydrothermal fluids in the Gilmore Dome area. Five ages on apatite from the Fort Knox gold deposit average 41 Ma, one from the Stepovich prospect is 80 Ma, and two from Pedro Dome average 67 Ma. Elevations of these samples overlap but their ages do not, indicating that each area experienced a different thermal history.Ages of apatite from the Fort Knox gold deposit decrease with elevation from 42 to 36 Ma but have data trends indicative of complex cooling. Two ~51 Ma ages on zircon indicate that maximum temperatures approached or exceeded ~180 °C. An alteration assemblage of chalcedony + zeolite + calcite + clay in the deposit resulted from deposition by a paleo-hydrothermal system. The data suggest that the system followed a complex cooling path from > 180 to < 110 °C between 51 and 36 Ma, and that final cooling to below 60 °C occurred after ~25 Ma.The 80 Ma age from Stepovich prospect either resulted from cooling after intrusion of the underlying pluton (~90 Ma) or records postintrusion thermal overprinting sometime after ~50 Ma. The 67 Ma samples from Pedro Dome may also have experienced partial age reduction during later heating. The differences in the data from the different areas and the presence of a late alteration assemblage at Fort Knox suggest that the fluids responsible for heating were largely confined to the highly fractured and porous Fort Knox pluton.
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Wang, Wei Bing, He Xue, Fu Qiang Yang, and Kun Liu. "Effects of Grain Size on Crack Tip Mechanical Fields of Intergranular Cracking." Advanced Materials Research 1004-1005 (August 2014): 1147–51. http://dx.doi.org/10.4028/www.scientific.net/amr.1004-1005.1147.
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Intergranular stress corrosion cracking is one of important failure form of structural materials in nuclear power plants, and the initiation and development of crack at grain boundary are affected by the grain size of materials. The macroscopic model and mesoscopic model of crack propagation was established by using finite element method, and the effects of grain size on fracture parameters such as Mises stress, the maximum principal stress and equivalent plastic strain nearby crack tip were studied. The results indicate that the distribution of Mises stress and equivalent plastic strain are discontinuity at grain boundary, and the maximum principal stress locates at grain boundary. The Mises stress, maximum principal stress and equivalent plastic strain nearby crack tip increase with the increasing of grain size.
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Abood, Saleel Hussein, and Majid Habeeb Faidh-Allah. "Analysis of Prosthetic Running Blade of Limb Using Different Composite Materials." Journal of Engineering 25, no. 12 (December 1, 2019): 15–25. http://dx.doi.org/10.31026/j.eng.2019.12.02.
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Prostheses are used as an alternative to organs lost from the body. Flex-Foot Cheetah is considered one of the lower limb prostheses used in high-intensity activities such as running. This research focused on testing two samples of Flex-Foot Cheetah manufactured of two various materials (carbon, glass) with polyester and compare between them to find the foot with the best performance in running on the level of professional athlete. In the numerical analysis, the maximum principal stress, maximum principal elastic strain, strain energy; finally, the blade total deformation were calculated for both feet. In experimental work, the load-deflection test was done for foot to calculate the bending the results were very close to the numerical results and the curve of the carbon foot sample was lower than that for the glass foot sample that indicates the strength of carbon fiber.
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Huang, Erick Ceasar, Sharon Sherry Huang, and Cheng-Hua Tsai. "A Study on the Minimum and Maximum Sum of C2 Problem in IMO2014." Journal of Mathematics Research 9, no. 5 (August 8, 2017): 1. http://dx.doi.org/10.5539/jmr.v9n5p1.
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The focus of this paper is primarily on a problem: the principle of the extreme value under some special operations. After enumerating from the maximum sum to minimum and solving these cases, I found that the use of the two mathematical models enabled the derivation of the general form of the use of the two mathematical models enabled the derivation of the general form of the maximum and the minimum sum. This program looks into the principles of minimum and maximum sum, and the various patterns that come along with it. In order to further discuss this kind of problems, we set up other different conditions, solving them with two mathematical models and principle of sequence recursive relationship, induction proof, etc. We also extend all these problems to explore the generating functions of the maximum and the minimum sum with operating number m based on the parity of the number of papers. Finally, using computer generated software, we demonstrate the various sums of a particular state, along with coming up with a general rule for all states that can predict the maximum and the minimum sum through the usage of induction.
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ELSEN, J. M. "Sélection et introgression assistées par marqueurs." INRAE Productions Animales 13, HS (December 22, 2000): 233–37. http://dx.doi.org/10.20870/productions-animales.2000.13.hs.3844.
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La sélection et, plus généralement, l’amélioration génétique assistée par marqueurs est une des perspectives très importantes d’application de la génétique moléculaire. Les principes de base en sont rappelés et les modalités de mise en oeuvre rapidement décrites. L’efficacité de ces méthodes d’amélioration nouvelles est estimée relativement à celle des méthodes traditionnelles basées sur les seules informations quantitatives et généalogiques. Elle est d’autant plus grande que les valeurs génétiques sont difficiles à estimer (héritabilité faible, caractère exprimé dans un seul sexe ...). Le gain maximum sera obtenu en modifiant l’organisation de la sélection (pré-sélection des reproducteurs, introgression génique).
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Le Pichon, Céline, Marc Mingelbier, Maëlle Legros, Aline Foubert, and Philippe Brodeur. "Effets du réseau routier sur la connectivité des frayères du grand brochet (Esox lucius) au lac Saint-Pierre (fleuve Saint-Laurent, Canada)." Le Naturaliste canadien 142, no. 1 (November 22, 2017): 78–91. http://dx.doi.org/10.7202/1042016ar.
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Afin de compléter le portrait des pressions agissant sur les habitats aquatiques de la plaine d’inondation du lac Saint-Pierre, une analyse géomatique avancée évalue les effets du réseau routier sur la connectivité des frayères et des nourriceries du grand brochet (Esox lucius). Les résultats révèlent des effets négatifs sur les habitats à fort potentiel lorsque le débit à Sorel dépasse 12 000 m3.s−1 (récurrence : de 1 à 2 ans), créant des pertes directes au niveau des emprises (maximum : 142 ha) et de la fragmentation entre les habitats situés de part et d’autre des routes (maximum : 39 ha). Ces effets, principalement circonscrits dans la région nord-ouest du lac, dépendent largement des conditions hydrologiques entre la période de fraie et la première semaine de vie des larves. Les mesures de connectivité soulignent l’importance des ponceaux fonctionnels et du réseau hydrographique de la zone littorale, éléments essentiels à l’interconnexion des habitats. Il apparaît que les répercussions du réseau routier, bien qu’elles soient moindres que celles provoquées par les pratiques agricoles intensives ou encore par la régularisation du débit, demeurent non négligeables. La présente étude identifie les habitats à fort potentiel et des corridors de connectivité constituant des milieux prioritaires à protéger ou à restaurer.
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Lei, Jinhui, and Xiyan Tian. "Proposal of a new Maximum Lifetime Communication Model of Wireless Sensor Network." International Journal of Online Engineering (iJOE) 12, no. 10 (October 31, 2016): 31. http://dx.doi.org/10.3991/ijoe.v12i10.6202.
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<p style="margin: 0in 0in 10pt;"><span style="-ms-layout-grid-mode: line;"><span style="font-family: Times New Roman; font-size: small;">One new maximum lifetime communication model of wireless sensor network is proposed in this thesis and the model is based on conditions of base station with multiple sources and multiple links and the data generated from the source node can be transmitted to several base stations through multiple links. In this chapter, energy limitation and data stream conservation principles of a wireless sensor network are used to establish a linear planning model, and attaining the maximum lifetime of the network is the optimal objective to establish a model with multiple restrictions restricted by energy and bandwidth. The basic element influencing the lifetime of a wireless sensor network is the data forwarding rate. The lifetime of nodes will become longer with the decrease of node data. In this thesis, the data size of network nodes is taken as sub-optimization objective and the distributed heuristic algorithm will be used to solve the linear planning model. In the end, a simulation experiment is conducted to verify yhe performance of the communication model and indicate that the proposed model can effectively increase network lifetime.</span></span></p>
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Cho, S. M., A. H. Seltzer, and M. Blackbourn. "Thermal-Hydraulic Analysis of the Fort St. Vrain Modular Vault Dry Store System." Journal of Engineering for Gas Turbines and Power 113, no. 4 (October 1, 1991): 522–29. http://dx.doi.org/10.1115/1.2906272.
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A passive, natural thermosyphon, air-cooled modular vault dry store (MVDS) system is being constructed for the storage of nuclear spent fuel for the Fort St. Vrain (FSV) Nuclear Power Station. In support of this FSV-MVDS system, thermal-hydraulic design analyses have been performed. The objective of the analyses is to determine flow and temperature distributions within the system and thus to ensure that the maximum fuel element temperatures shall not exceed specified design limit values under various loading and unloading conditions. This paper presents the method of analysis and discusses the resulting thermal-hydraulic characteristics of the MVDS system.
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Gonzalez, Wilma B. Aleman, Jean M. Self-Trail, W. Burleigh Harris, Jessica Pierson Moore, and Kathleen M. Farrell. "Depositional sequence stratigraphy of Turonian to Santonian sediments, Cape Fear arch, North Carolina Coastal Plain, USA." Stratigraphy 16, no. 1 (December 11, 2020): 293–314. http://dx.doi.org/10.29041/strat.17.4.293-314.
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ABSTRACT: A new sequence stratigraphic framework for Turonian to Santonian (94-84 Ma) sediments is established using data from the USGS Kure Beach and Elizabethtown cores collected from the Atlantic Coastal Plain of North Carolina (NC). These sediments represent some of the oldest marine units deposited on the southeastern Atlantic Coastal Plain and record the early development of a clastic wedge atop crystalline basement. Sediments were deposited as transitional marginal-marine to marine units in a complex interplay of fluvial, estuarine, and shelf environments. Repetitive lithologies and minimal biostratigraphic control requires an integrated analysis of grain-size data, geophysical logs, biostratigraphy, and 87Sr/86Sr isotopic data to identify systems tracts and establish a sequence stratigraphic framework. From this integrated approach, three Turonian to Santonian sequences in the Elizabethtown core and six in the Kure Beach core are identified. The new sequences from oldest to youngest are Clubhouse II, Fort Fisher I, Fort Fisher II, Collins Creek I, Collins Creek II, Pleasant Creek I, and Pleasant Creek II. Sequences from North Carolina document significant shifts of global and regional sea-level during greenhouse conditions in the early Late Cretaceous. Maximum sea-level rise occurred globally during the early Turonian and is documented from the marine sediments of the Clubhouse II sequence. This sequence is unconformably overlain by terrestrial sediments deposited during a major fall in sea level and maximum progradation of the shoreline, as evidenced by the Fort Fisher I sequence. Global sea-level rise in the Coniacian resulted in the deposition of the Fort Fisher II sequence, which is present only in the Kure Beach core. Local marine circulation and erosion on the shelf is suggested by the absence of the Collins Creek I sequence at Kure Beach; this sequence is present only in the up-dip Elizabethtown core. Activation of a possible buried fault structure along the Cape Fear arch resulted in the formation of a regional depocenter during the late Coniacian to early Santonian and is reflected in the unusual thickness of the Collins Creek II and Pleasant Creek I sequences. The return to a more global sea-level influence occurred in the late Santonian with the deposition of the Pleasant Creek II sequence. A comparison of temporal distribution of sequences in the Elizabethtown and Kure Beach cores to corresponding sequences in New Jersey indicates significant differences in erosional and tectonic processes in the Cape Fear region during the Turonian and Santonian.
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Fan, Hao, Lianguo Wang, and Kai Wang. "Stability Analysis of Surrounding Rock in Circular Tunnels Based on Critical Support Pressure." Advances in Civil Engineering 2020 (October 16, 2020): 1–9. http://dx.doi.org/10.1155/2020/8870928.
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Accurate calculation for the critical support pressure of tunnels plays an important role in tunnel stability evaluation and support design. In this study, a mechanical model for circular tunnels is developed. Considering the intermediate principal stress and strain-softening characteristic of rock mass, the critical support pressure when the plastic zone and damage zone begin to occur is determined based on the unified strength criterion and strain-softening model. Through the example study, the critical support pressure under different intermediate principal stress coefficient is solved. Furthermore, the effect of initial field stress, softening coefficient, and maximum damage variable on the critical support pressure are also discussed. The results show that the critical support pressure and radii of plastic and damage zones all decrease with the increase of the intermediate principal stress coefficient. The larger the initial field stress, the larger the critical support pressure. The softening coefficient and maximum damage variable of rock mass has no influence on the critical support pressure when the plastic zone begins to form, but has a significant effect on the critical support pressure when the damage zone begins to form. As softening coefficient increases and maximum damage variable decreases, the critical support pressure when the damage zone which begins to form increases. Data presented in this contribution provide significant theoretical insights into evaluating tunnel stability and support system reliability.
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Mahabir, C., F. E. Hicks, C. Robichaud, and A. Robinson Fayek. "Forecasting breakup water levels at Fort McMurray, Alberta, using multiple linear regression." Canadian Journal of Civil Engineering 33, no. 9 (September 1, 2006): 1227–38. http://dx.doi.org/10.1139/l06-067.
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Spring breakup on northern rivers can result in ice jams that present severe flood risk to adjacent communities. Such events can occur extremely rapidly, leaving little or no advanced warning to residents. Fort McMurray, Alberta, is one such community, and at present no forecasting model exists for this site. Many of the previous studies regarding ice jam flood forecasting methods, in general, cite the lack of a comprehensive database as an obstacle to statistical modelling. This paper documents the development of an extensive database containing 106 variables, and covering the period from 1972 to 2004, that was created for ice jam forecasting on the Athabasca River. Through multiple linear regression analysis, equations were developed to model the maximum water level during spring breakup. The optimal model contained a combination of hydrological and meteorological data collected from early fall until the day before river ice breakup. The number of historical years of data, rather than the scope of variables, was found to be the major limitation in verifying the results presented in this study.Key words: river ice, breakup jam, multiple linear regression.
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Ndogmo, Jean-Claude. "Some variational principles associated with ODEs of maximal symmetry. Part 2: The general case." Journal of Applied Analysis 24, no. 2 (December 1, 2018): 175–83. http://dx.doi.org/10.1515/jaa-2018-0017.
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Abstract Variational and divergence symmetries are studied in this paper for the whole class of linear and nonlinear equations of maximal symmetry, and the associated first integrals are given in explicit form. All the main results obtained are formulated as theorems or conjectures for equations of a general order. A discussion of the existence of variational symmetries with respect to a different Lagrangian, which turns out to be the most common and most readily available one, is also carried out. This leads to significantly different results when compared with the former case of the transformed Lagrangian. The latter analysis also gives rise to more general results concerning the variational symmetry algebra of any linear or nonlinear equations.
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Qin, Zhongcheng, Bin Cao, Yongle Liu, and Tan Li. "Study on In Situ Stress Measurement and Surrounding Rock Control Technology in Deep Mine." Geofluids 2020 (September 8, 2020): 1–12. http://dx.doi.org/10.1155/2020/8839333.
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In situ stress is the direct cause of roadway deformation and failure in the process of deep mining activities. The measured data of in situ stress in the Shuanghe coal mine show that the maximum principal stress is 44.94~50.61 MPa, and the maximum principal stress direction is near horizontal direction, which belongs to tectonic stress field. The maximum horizontal principal stress is 1.66~1.86 of the vertical stress. The horizontal principal stress controls the deep stress field. According to the measured data of in situ stress, the high-strength prestress bolt and cable collaborative support form is designed in the Shuanghe coal mine. Based on the stress field research of bolt and cable, the optimal prestress ratio of bolt and cable is proposed as 3. When the prestress ratio of bolt and cable is constant, the smaller the length ratio of bolt and cable is, the better the effect of prestressed field formed by cooperative support is. The results are applied to the support design of the mining roadway in the Shuanghe coal mine. Through the field monitoring test results, it is found that the maximum roof subsidence is 86 mm, the maximum floor deformation is 52 mm, and the maximum deformation of two sides is 125 mm. The surrounding rock control effect of the roadway is good, and the surrounding rock deformation conforms to the engineering technology standard requirements. The research results of this paper can provide some reference for the surrounding rock support of high ground stress mining roadway under similar conditions.
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Bazˇant, Z. P., and Yuan-Neng Li. "Stability of Cohesive Crack Model: Part I—Energy Principles." Journal of Applied Mechanics 62, no. 4 (December 1, 1995): 959–64. http://dx.doi.org/10.1115/1.2896029.
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The paper deals with a cohesive crack model in which the cohesive (crack-bridging) stress is a specified decreasing function of the crack-opening displacement. Under the assumption that no part of the crack undergoes unloading, the complementary energy and potential energy of an elastic structure which has a cohesive crack and is loaded by a flexible elastic frame is formulated using continuous influence functions representing compliances or stiffnesses relating various points along the crack. By variational analysis, in which the derivatives of the compliance or stiffness functions with respect to the crack length are related to the crack-tip stress intensity factors due to various unit loads, it is shown that the minimizing conditions reduce to the usual compatibility or equilibrium equations for the cohesive cracks. The variational equations obtained can be used as a basis for approximate solutions. Furthermore, the conditions of stability loss of a structure with a growing cohesive crack are obtained from the condition of vanishing of the second variation of the complementary energy or the potential energy. They have the form of a homogeneous Fredholm integral equation for the derivatives of the cohesive stresses or crack opening displacements with respect to the crack length. Loadings with displacement control, load control, or through a flexible loading frame are considered. Extension to the analysis of size effect on the maximum load or maximum displacement are left to a subsequent companion paper.
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Rosenberger, S., F. P. Helmus, S. Krause, A. Bareth, and U. Meyer-Blumenroth. "Principles of an enhanced MBR-process with mechanical cleaning." Water Science and Technology 64, no. 10 (November 1, 2011): 1951–58. http://dx.doi.org/10.2166/wst.2011.765.
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Up to date, different physical and chemical cleaning protocols are necessary to limit membrane fouling in membrane bioreactors. This paper deals with a mechanical cleaning process, which aims at the avoidance of hypochlorite and other critical chemicals in MBR with submerged flat sheet modules. The process basically consists of the addition of plastic particles into the loop circulation within submerged membrane modules. Investigations of two pilot plants are presented: Pilot plant 1 is equipped with a 10 m2 membrane module and operated with a translucent model suspension; pilot plant 2 is equipped with four 50 m2 membrane modules and operated with pretreated sewage. Results of pilot plant 1 show that the establishment of a fluidised bed with regular particle distribution is possible for a variety of particles. Particles with maximum densities of 1.05 g/cm3 and between 3 and 5 mm diameter form a stable fluidised bed almost regardless of activated sludge concentration, viscosity and reactor geometry. Particles with densities between 1.05 g/cm3 and 1.2 g/cm3 form a stable fluidised bed, if the velocity at the reactor bottom is sufficiently high. Activities within pilot plant 2 focused on plant optimisation and the development of an adequate particle retention system.
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Trivaudey, F., and P. Delobelle. "High Temperature Creep Damage Under Biaxial Loading—Part I: Experiments." Journal of Engineering Materials and Technology 112, no. 4 (October 1, 1990): 442–49. http://dx.doi.org/10.1115/1.2903355.
Full textAbstract:
The respective influences of the Von-Mises equivalent stress and of the maximum principal stress on the high temperature creep damage of two industrial alloys (INCO 718 and 17–21 SPH stainless steel) are pointed out in a quantitative way through tensile-torsion biaxial tests. Through inversions of the shear component, the important part taken by the principal direction corresponding to the maximum principal stress is also shown. Opposite results are observed according to whether the alloy suffers cyclic hardening as 17-12 SPH does or cyclic softening which is the case of INCO 718. These results are supported by metallographic observations. They demand an anisotropic form for the damage variable D, while besides a time dependence kinetics equation must include the part taken by the strain. The bases of the formulation are described in Part II.
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Upadhaya, Poojan, Hongbo Du, and Raghava R. Kommalapati. "Meteorological Detrending of Ozone at Three Sites in the Dallas-Fort Worth Area: Application of KZ Filter Method." Atmosphere 11, no. 11 (November 13, 2020): 1226. http://dx.doi.org/10.3390/atmos11111226.
Full textAbstract:
The Dallas-Fort Worth (DFW) area that experiences high temperature and intense solar radiation falls into the moderate nonattainment classification. The variation in meteorological parameters plays an important role in ambient ozone levels variation. Meteorological influences need to be decoupled from ozone data for long-term trend analysis. Temporal separation of maximum daily average 8-h ozone (MDA8 ozone), maximum daily temperature (TMAX), daily average solar radiation (DASR), and daily average wind speed (DAWS) were conducted using Kolmogorov-Zurbenko (KZ) filter for ozone records at Keller (C17), Arlington (C61), Red Bird (C402) monitoring stations in the DFW area from 2003 to 2017. Temporal separation, regression analysis, and meteorological detrending were performed. The long-term component had a clear and stable trend. The contribution of the long-term component to total variation was negligible, which is less than 2%. This is due to the removal of the data noise from the original time series data. The seasonal component had a major contribution (55% to 72%) in the total variation of the maximum temperature and solar radiation. However, the short-term component was dominant in the total variation of the MDA8 ozone (41–54%) and wind speed (68–79%). Regression analysis showed the baseline component bears the highest correlation than the short-term and raw. Solar radiation had the highest correlation to the MDA8 ozone, followed by temperature data in all three stations. Meteorological detrending showed the detrended long-term ozone had an increasing trend. The increasing trend was significant at C402 with a trend of 0.19 ± 0.006 ppb/y (0.398 R2), whereas slight increasing trends were found at C17 (0.072 ± 0.006 (0.107 R2)) and at C61 (0.019 ± 0.007 (0.005 R2)). The increasing trend of long-term components of MDA8 ozone was justified by the increasing level of NOx and VOCs from the mobile sources in the DFW area.