738 research outputs found

    L’influence de l’exploitation forestière sur la concentration des particules dans les petits cours d’eau de la Beauce, Québec

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    Cette étude a pour but d'évaluer l'influence de l'exploitation forestière sur l'augmentation de la quantité de sédiments en suspension dans cinq cours d'eau soumis à différents types de coupe. Lorsque les exploitations sont effectuées sans aucun souci de protection et que la machinerie forestière a libre accès au cours d'eau, les concentrations des sédiments inorganiques et organiques en suspension se maintiennent respectivement au-dessus de 1 000 et 500 ppm durant la coupe. Les maxima atteignent 197 000 et 65 000 ppm. Lorsque l'on garde la machinerie à une certaine distance des cours d'eau et que les arbres sont abattus en direction opposée, l'augmentation de la concentration de particules en suspension dans l'eau est faible. Il en va de même lorsque les cours d'eau sont protégés par des bandes boisées. Les concentrations des sédiments en suspension dans ces deux derniers cas demeurent généralement sous 35 ppm. Par contre, l'efficacité de la bande boisée est fortement atténuée par les passages de la machinerie, par l'arrivée d'un tributaire bouleversé par les opérations forestières ou par le creusage des tranchées d'égouttement des voies d'accès. Ainsi, les concentrations de sédiments inorganiques et organiques en suspension dépassent fréquemment 100 ppm et atteignent respectivement des maxima de 900 â 2 000 ppm.The influence of logging operations on the input of suspended matters is evaluated on five streams subjected to different logging patterns. When the operations are carried out without protective measures, including tractor crossing of watercourses, the concentrations of inorganic and organic suspended matters remain above 1,000 and 500 ppm respectively during logging. The maxima reach 197,000 and 65,000 ppm respectively. Keeping the tractors away from the streams and felling the trees in the opposite direction of the streams minimize the increase of the suspended load. Similar protection is offered by leaving standing timber strips. These two latter types of protection keep the concentration of suspended sediments below 35 ppm. On the other hand the efficiency of the green strip is greatly reduced by tractors using it, by the crossing of a disturbed tributary, or by the digging of road drains. Thus, the concentrations of suspended sediments frequently go beyond 100 ppm and the maxima reach 900 and 2,000 ppm for the inorganic and organic fraction respectively.Der Einfluss von Waldbautâtigkeit auf die Menge der Schwebstoffe wurde in funf Bachen, in Gebieten mit verschiedenartigen WaIdbaumethoden ausgewertet. Wenn die Arbeit ohne jegliche Schutzmassnahmen vorgeht und die Waldbaumaschinen die Wasserlaufe durchqueren, halt sich das Niveau fur organische und inorganische Schwebstoffe bei jeweils 1000 und 500 ppm, wâhrend des Fallens. Die Maxima erreichen jeweils 197000 und 65000 ppm. Die Maschinen ausserhalb der wasserlaufe zu halten, und die Baume in entgegengesetzter Richtung zum Wasserlauf zu fallen vermindert den Anstieg der Schwebstoffe. Ahnliche Beschutzung wird durch stehen gelassene Waldstreifen erreicht. Diese beiden Beschutzungstypen halten die Konzentration der Schwebstoffe unter 35 ppm. Andererseits wird die Leistungsfahigkeit der grunen Streifen durch Treckeruberquerungen. oder durch das Graben von Entwâsserungskanâlen fur die Wege sehr vermindert. So erhebt sich die Konzentration der inorganischen und organischen Schwebstoffe hâufig auf mehr als 100 ppm und erreicht Maxima von jeweils 900 und 2000 ppm

    Alien Registration- Plamondon, Leo P. (Sanford, York County)

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    https://digitalmaine.com/alien_docs/3631/thumbnail.jp

    Accumulation et fonte de la neige en milieux boisé et déboisé

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    Les auteurs présentent une étude des caractéristiques physiques du couvert de neige en relation avec l'altitude, l'exposition et le couvert forestier. L'expérience s'est déroulée à la forêt Montmorency, sise à 80 km au nord de Québec. Au cours des hivers 1981 et 1982, l'équivalent en eau maximal de la neige, pour l'ensemble du bassin du lac Laflamme, a été de 28 et 29 cm, respectivement. Durant cette période, les mesures effectuées n'ont pas permis de détecter l'effet des faibles différences d'altitude (50 m) sur l'accumulation de la neige. L'équivalent en eau de la neige était maximal dans les milieux découverts et apparaissait plus important sous les jeunes peuplements que sous les vieux. Les jeunes sapinières, entourées d'arbres plus hauts, agissent comme des pièges à neige. L'influence de l'exposition ne ressort que durant la période de fonte, accélérée d'une semaine sur les flancs sud. La fonte en sous-bois dure un mois et demi en moyenne et est écourtée d'une à deux semaines dans les sites découverts. Un modèle de fonte, basé sur les degrés-jours, est finalement adapté. Le coefficient de fonte est rajusté en fonction de deux périodes distinctes par la densité du manteau nival ou les degrés-jours cumulés.A study of physical characteristics of the snow cover in relation to altitude, aspect and forest cover, is presented in this paper. The experimental site is located at Montmorency forest, 80 km north of Québec City. During the winters of 1981 and 1982, the snow water equivalent for the lake Laflamme watershed reached a maximum of 28 and 29 cm, respectively. The effect on snow accumulation by the small elevation range (50 m) was not detectable by our measurements. The snow water equivalent was greatest in open areas and appeared greater under the young than the older stands. The young fir associations, surrounded by higher trees, act as snow traps. The aspect plays a role during the melting period only, which is shortened by one week on south exposures. Snowmeit lasts one and a half month in average under the cover and is shortened by one to two weeks in the open. A snowmeit model, based on degree-days, is finally calibrated. The melt coefficient is readjusted for two periods separated by snow density or cumulative degree-days.Die Autoren legen eine Studie vor, die die Beziehung der physischen Merkmale der Schneedecke zu Hôhe, Himmelsrichtung und Bewaldung untersucht. Der Versuch wurde im WaId Montmorency, der 80 km nôrdlich von Québec liegt, durchgefùhrt. Wàhrend der Winter 1981 und 1982 war das maximale Wasserâquivalent der Schneemenge 28 cm bzw. 29 cm fur das gesamte Becken des Laflamme-Sees. Wahrend dieser Période konnten die durchgefuhrten Messungen keinerlei Einflup der schwachen Hôhenunterschiede (50 m) auf die Menge des angesammelten Schnees feststellen. Das der Schneemenge entsprechende Wasserâquivalent war maximal in den freien Gebieten und schien grosser unter den jungen Baumbestanden als unter den alten. Die jungen Tannenwâlder, die von hôheren Baurnen umgeben sind, wirken wie Schneefallen. Der EinfluB der Himmelsrichtung wird erst wâhrend der Zeit der Schneeschmelze spurbar, die auf den Sudflanken urn eine Woche kùrzer ist. Die Schneeschmelze im WaId dauert im Durchschnitt eineinhalb Monate und ist ein bis zwei Wochen kurzer in den offenen Gelànden. Ein Schneeschmelze-Modell auf der Basis Grade-Tage wird schlieplich geeicht. Der Schmelzkoeffizient wird zwei Perioden angepaBt, die sich durch die Dichte der Schneedecke oder die kumulierten Grade-Tage unterscheiden

    Intergenerational Pathways From Reflective Functioning to Infant Attachment Through Parenting

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    The aim of this prospective study was to examine temporal pathways from mothers’ reflective functioning (RF) through parenting to infant attachment measured more than 16 months later. Participants were 88 mother–infant dyads from demographically diverse backgrounds and included a group of mothers with histories of childhood maltreatment. RF was assessed using the RF rating of the Adult Attachment Interview before the birth of the baby. Parenting was assessed when the infants were 6 months old using the Maternal Sensitivity scale, as well as when they were 16 months using the Disconnected and Extremely Insensitive Parenting scale. Infant attachment was assessed when the infants were 16 months old using the Strange Situation. As hypothesised, the study findings showed that mothers’ mentalization regarding their own early attachment relationships was associated with later parenting and infant attachment. Negative parenting behaviours explained the link between mothers’ RF about their own attachment relationships and infant attachment disorganization. The findings suggest that mothers’ mentalization about their early attachment relationships has important implications in the transition to becoming parents themselves. Mentalization appears to be particularly important in helping mothers screen and inhibit negative parenting behaviours that would otherwise undermine infant attachment security and organization

    A mediation meta-analysis of the role of maternal responsivity in the association between socioeconomic risk and children's language

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    This meta-analysis tested maternal responsivity as a mediator of the association between socioeconomic risk and children's preschool language abilities. The search included studies up to 2017 and meta-analytic structural equation modeling, allowed us to examine the magnitude of the indirect effect across 17 studies (k = 19). The meta-analysis included 6433 predominantly White, English speaking children (Mage  = 36 months; 50% female) from Western, industrialized countries. All paths in the model were statistically significant, notably, the indirect effect was significant (b = -.052), showing that maternal responsivity may be a proximal intervening variable between socioeconomic risk and children's language development. Moderator analyses found that the indirect effect was stronger for sensitive parenting than warmth and when parenting was assessed in the family home

    Tuning continua and keyboard layouts

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    Previous work has demonstrated the existence of keyboard layouts capable of maintaining consistent fingerings across a parametrized family of tunings. This paper describes the general principles underlying layouts that are invariant in both transposition and tuning. Straightforward computational methods for determining appropriate bases for a regular temperament are given in terms of a row-reduced matrix for the temperament-mapping. A concrete description of the range over which consistent fingering can be maintained is described by the valid tuning range. Measures of the resulting keyboard layouts allow direct comparison of the ease with which various chordal and scalic patterns can be fingered as a function of the keyboard geometry. A number of concrete examples illustrate the generality of the methods and their applicability to a wide variety of commas and temperaments, tuning continua and keyboard layouts

    Spectral tools for Dynamic Tonality and audio morphing

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    The analysis-resynthesis method used by the spectral toolbox allows the independent control of both frequency and amplitude for every partial in a given sound. The spectral toolbox begins by separating the 'signal' from the 'noise' which allows the peaks in the spectrum to be treated differently from the wide-band components. The spectral mapping technology is used to map the input to a fixed destination spectrum G like the SpT.Ntet routine maps all partials of the input sound to scale steps of the N-tone equal tempered scale that can be used to create sounds that are particularly appropriate for use in a given N-TET scale. Spectral morphing generates sound that moves smoothly between a source spectrum F and a destination spectrum G over a specified time t. A Dynamic Tonality synthesizer like Trans-FormSynth has a small number of parameters that enable many musically useful, and relatively, unexplored features like the continuous parameters α,β and γ move the tuning between a number of equal temperaments, non-equal temperaments and circulating temperaments

    Sigma-lognormal modeling of speech

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    Human movement studies and analyses have been fundamental in many scientific domains, ranging from neuroscience to education, pattern recognition to robotics, health care to sports, and beyond. Previous speech motor models were proposed to understand how speech movement is produced and how the resulting speech varies when some parameters are changed. However, the inverse approach, in which the muscular response parameters and the subject’s age are derived from real continuous speech, is not possible with such models. Instead, in the handwriting field, the kinematic theory of rapid human movements and its associated Sigma-lognormal model have been applied successfully to obtain the muscular response parameters. This work presents a speech kinematics-based model that can be used to study, analyze, and reconstruct complex speech kinematics in a simplified manner. A method based on the kinematic theory of rapid human movements and its associated Sigma-lognormal model are applied to describe and to parameterize the asymptotic impulse response of the neuromuscular networks involved in speech as a response to a neuromotor command. The method used to carry out transformations from formants to a movement observation is also presented. Experiments carried out with the (English) VTR-TIMIT database and the (German) Saarbrucken Voice Database, including people of different ages, with and without laryngeal pathologies, corroborate the link between the extracted parameters and aging, on the one hand, and the proportion between the first and second formants required in applying the kinematic theory of rapid human movements, on the other. The results should drive innovative developments in the modeling and understanding of speech kinematics

    T-systems and Y-systems in integrable systems

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    The T and Y-systems are ubiquitous structures in classical and quantum integrable systems. They are difference equations having a variety of aspects related to commuting transfer matrices in solvable lattice models, q-characters of Kirillov-Reshetikhin modules of quantum affine algebras, cluster algebras with coefficients, periodicity conjectures of Zamolodchikov and others, dilogarithm identities in conformal field theory, difference analogue of L-operators in KP hierarchy, Stokes phenomena in 1d Schr\"odinger problem, AdS/CFT correspondence, Toda field equations on discrete space-time, Laplace sequence in discrete geometry, Fermionic character formulas and combinatorial completeness of Bethe ansatz, Q-system and ideal gas with exclusion statistics, analytic and thermodynamic Bethe ans\"atze, quantum transfer matrix method and so forth. This review article is a collection of short reviews on these topics which can be read more or less independently.Comment: 156 pages. Minor corrections including the last paragraph of sec.3.5, eqs.(4.1), (5.28), (9.37) and (13.54). The published version (JPA topical review) also needs these correction
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