Showing papers by "Université du Québec à Montréal published in 1986"
TL;DR: The aim of this paper is to argue that the process of code-mixing is constrained by the government relation that holds between the constituents of a sentence.
Abstract: The aim of this paper is to argue that the process of code-mixing is constrained by the government relation that holds between the constituents of a sentence. The government constraint replaces a number of specific constraints that have been proposed in the literature to account for apparently ‘impossible’, ‘ungrammatical’ or ‘non-occurring’ types of intra-sentential switches. Code-mixing is a form of linguistic behaviour which produces utterances consisting of elements taken from the lexicons of different languages. Some examples are given in (1).
330 citations
01 Jan 1986
292 citations
TL;DR: In this paper, the authors considered the problem of location-routing where a weight is assigned to each site and where sites are to be visited by vehicles having a given capacity and the solution must be such that the sum of the weights of sites visited on any given route does not exceed the capacity of the visiting vehicle.
Abstract: In location-routing problems, the objective is to locate one or many depots within a set of sites (representing customer locations or cities) and to construct delivery routes from the selected depot or depots to the remaining sites at least system cost. The objective function is the sum of depot operating costs, vehicle acquisition costs and routing costs. This paper considers one such problem in which a weight is assigned to each site and where sites are to be visited by vehicles having a given capacity. The solution must be such that the sum of the weights of sites visited on any given route does not exceed the capacity of the visiting vehicle. The formulation of an integer linear program for this problem involves degree constraints, generalized subtour elimination constraints, and chain barring constraints. An exact algorithm, using initial relaxation of most of the problem constraints, is presented which is capable of solving problems with up to twenty sites within a reasonable number of iterations.
180 citations
TL;DR: In this paper, the evidence for a climatic event in Atlantic Canda was presented, which involved a warming trend before 11,000 yr BP that was interrupted by a cold period which persisted until the abrupt Holocene warming at ∼10, 000 yr BP.
Abstract: Attempts1–5 to relate late-glacial events in northeastern North America to the well-documented climato- and chrono-stratigraphy of Europe and the British Isles6 have not been considered convincing because the evidence presented was from isolated sites, and could therefore be interpreted as local fluctuations not related to a general, widespread climatic change7–10. However, recent palyno-logical studies in northeastern North America postulating a late-glacial climatic oscillation11–15 have caused renewed interest in relating such an oscillation to the Allerod/younger Dryas event. We have extended our preliminary results from Nova Scotia and New Brunswick13,14, and here present the evidence for a climatic event in Atlantic Canda. This event involved a warming trend before 11,000 yr BP that was interrupted by a cold period which persisted until the abrupt Holocene warming at ∼10,000 yr BP. We propose a possible mechanism to link this event with that of Europe.
169 citations
TL;DR: An exact algorithm for the asymmetrical capacitated vehicle routing problem, i.
Abstract: The aim of this article is to develop an exact algorithm for the asymmetrical capacitated vehicle routing problem, i. e., the multiple traveling salesman problem subject to capacity restrictions. The problem is solved by means of a branch and bound tree in which subproblems are modified assignment problems subject to some restrictions. Two branching rules and three partitioning rules are examined. Computational results for problems involving up to 260 nodes (cities) are reported.
164 citations
TL;DR: In this article, a model for the evolution of the late Archaean Abitibi greenstone belt of the Superior Province of Canada is proposed based on structural, geochemical, sedimentological and geochronological studies.
Abstract: Based on structural, geochemical, sedimentological and geochronological studies, we have formulated a model for the evolution of the late Archaean Abitibi greenstone belt of the Superior Province of Canada. The southern volcanic zone (SVZ) of the belt is dominated by komatiitic to tholeiitic volcanic plateaux and large, bimodal, mafic-felsic volcanic centres. These volcanic rocks were erupted between approximately 2710 Ma and 2700 Ma in a series of rift basins formed as a result of wrench-fault tectonics.The SVZ superimposes an older volcanic terrane which is characterized in the northern volcanic zone (NVZ) of the Abitibi belt and is approximately 2720 Ma or older. The NVZ comprises basaltic to andesitic and dacitic subaqueous massive volcanics which are cored by comagmatic sill complexes and layered mafic-anorthositic plutonic complexes. These volcanics are overlain by felsic pyroclastic rocks that were comagmatic with the emplacement of tonalitic plutons at 2717 ±2 Ma.The tectonic model envisages the SVZ to have formed in a series of rift basins which dissected an earlier formed volcanic arc (the NVZ). Analogous rift environments have been postulated for the Hokuroko basin of Japan, the Taupo volcanic zone of New Zealand and the Sumatra and Nicaragua arcs. The difference between rift related ‘submergent’ volcanism in the SVZ and ‘emergent’ volcanism in the NVZ resulted in the contrasting metallogenic styles, the former being characterized by syngenetic massive sulphide deposits, whilst the latter was dominated by epigenetic ‘porphyry-type’ Cu(Au) deposits.
124 citations
TL;DR: The results suggest that the constrictor effect of NPY on guinea pig coronary vessels results from a direct effect on vascular smooth muscle cells, is mediated by specific receptors and is likely to involve the participation of extracellular calcium ions.
119 citations
TL;DR: The authors examined the effects of competition on intrinsic motivation and found that subjects in the competition condition displayed less subsequent intrinsic motivation than did mastery-oriented subjects. But their results corroborate predictions based on cognitive evaluation theory (Deci & Ryan, 1985) that competition can have deleterious consequences on intrinsic motivations.
Abstract: This study examined the effects of competition on intrinsic motivation. Subjects (N = 23) were randomly assigned to conditions of competition or intrinsic-mastery orientation. In the competition condition, subjects were instructed to perform an interesting activity with the explicit goal of “beating” other participants. In the intrinsic-mastery orientation condition, subjects were told to do as well as they could while looking for novel ways to perform the activity. Results showed that subjects in the competition condition displayed less subsequent intrinsic motivation than did mastery-oriented subjects. The present findings corroborate predictions based on cognitive evaluation theory (Deci & Ryan, 1985) that competition can have deleterious consequences on intrinsic motivation.
119 citations
TL;DR: In this article, an initial 230Th232Th ratio in the detrital component was determined by ThU measurements on the 14C dated stromatolites, using this value a 230Th234U chronology was calculated.
112 citations
TL;DR: In this paper, the influence of culturally-related caretaking practices on motor development was investigated in Bambara infants between 4 a.m. and 4:30 a.k.a.
Abstract: The present study is the first exploratory step of a larger investigation focusing on the influence of culturally-related caretaking practices on motor development. Four Bambara infants between 4 a...
89 citations
TL;DR: In this article, the authors report on 34 new Th and U isotope measurements on Strombus Bubonius and Glycymeris glycymersis fossils from raised marine terraces in the Almeria area, southeastern Spain, which yield a coherent chronology that indicates the presence of warm water S. bubonius fauna in the Mediterranean basin.
Abstract: Single dates obtained on mollusk shells by the U-series nuclides method are highly unreliable, primarily because of the mobility of uranium isotopes. However, in several cases, a statistical approach was demonstrated to yield coherent chronologies in both continental and marine environments. The authors report on 34 new Th and U isotope measurements on Strombus Bubonius and Glycymeris glycymeris fossils from raised marine terraces in the Almeria area, southeastern Spain. The results yield a coherent chronology that indicates the presence of the warm water S. bubonius fauna in the Mediterranean basin. Reconsideration of the Tyrrhenian stratigraphy based on the presence of S. bubonius is thus required.
TL;DR: In this article, it was shown that it is NP-hard to decide whether the rounding holds or not for an instance of the cutting stock problem for which the rounding property does not hold.
01 Jan 1986
TL;DR: In this article, a new method for numerically solving the classical quasi-geostrophic omega equation is proposed, which integrates the omega equation upward using two bottom boundary conditions at the top of the boundary layer: ω and ∂ω/∂p.
Abstract: A new method for numerically solving the classical quasi-geostrophic omega equation is proposed. The method, in effect, integrates the omega equation upward using two bottom boundary conditions at the top of the boundary layer: ω and ∂ω/∂p. The former can be specified by using methods that use only surface data while the latter is calculated using information contained in the horizontal Laplacian of the surface pressure tendency field. As opposed to traditional solutions, the proposed method requires no explicit horizontal boundary condition, requires no data above the level at which ω is desired, nor constrains the static stability. When integrated to the level near the top of the atmosphere where ω is normally taken to be zero, the equation becomes a development equation that is similar to (and is shown to be more complete than) the Petterssen-Sutcliffe development equation. The new method to calculate omega is tested in a simple, analytic atmosphere and the solution is found to satisfy the cla...
01 Jan 1986
TL;DR: In this article, three palynostratigraphic units have been observed and tentatively dated by Th/U measurements on embedded fossil wood on Cape Breton Island (Nova Scotia), near the margin of the Wisconsinan ice sheet.
Abstract: On Cape Breton Island (Nova Scotia), near the margin of the Wisconsinan ice sheet, karst depressions in Mississippian gypsum-bearing rocks contain interglacial and interstadial organic-rich deposits. Three palynostratigraphic units have been observed and tentatively dated by Th/U measurements on embedded fossil wood. The first, dated at ca. 125 ka, may be assigned to the oceanic /sup 18/O substage 5e; thermophilous forests (Quercus, Ostrya, pinus strobus) developed in response to a climate warmer than the present. The second unit, rich in Abies balsamea pollen and dated at ca. 87 ka, may relate to the /sup 18/O substage 5a; it reflects a cool and wet climate not unlike that of today. The third unit probably spans part of the mid-Wisconsinan (/sup 18/O stage 3); it shows alternating boreal forest-tundra forest assemblages indicative of climatic oscillations during a generally cold interval.
01 Jan 1986
01 Jan 1986
01 Jan 1986
TL;DR: In this paper, the authors computed the stress induced by the topography and density heterogeneity in the lithosphere for two different tectonic regions of the North American plate and showed that these stresses are locally comparable in magnitude to the regional tectonics stress (~ 20-50 MPa).
TL;DR: In this paper, the authors analyse the solution set of first-order initial value differential problems of the form dy dx = ƒ(x, y), y(0) = 0 in the context of combinatorial species in the sense of A. Joyal (Adv. in Math. 42 (1981), 1−82).
TL;DR: In this paper, the Fourier transform infrared spectra of CHCl3 solutions containing a non-conjugated imine, R1HC=NR2 and an acid of the series HCl, HBr, HI, trichloro-, dichloro, monochloro-monobromo acetic acids and propionic acid have been recorded.
Abstract: The Fourier-transform infrared spectra of CHCl3 solutions containing a non-conjugated imine, R1HC=NR2 and an acid of the series HCl, HBr, HI, trichloro-, dichloro-, monochloro-, monobromo acetic acids and propionic acid have been recorded. Both the N+H and double bond stretching regions are examined. The results show that HCl, HBr and HI protonate the imine completely, trichloroacetic acid to about 90-95%, the other haloacetic acids to 55-80% and propionic acid to <10%. Considered as model studies for the problem of protonation in rhodopsins our results lead to the conclusion that with the relatively weak acids available in the pigments full protonation requires a stabilization mechanism which should be further investigated.
TL;DR: In this paper, the effect of short-term and continuous acidification on the primary production and biomass of periphyton was studied in seminatural conditions using an experimental device simulating streams ecosystems.
Abstract: The effect of short-term and continuous acidification on the primary production and biomass of periphyton was studied in seminatural conditions using an experimental device simulating streams ecosystems. After allowing periphytic algae to colonize unglazed ceramic tiles for 4 to 6 weeks under natural conditions, the pH of the water was lowered with sulfuric acid (H 2 SO 4 ) from 6.5 to 6.7 to 4 to 4.6 for short periods (12 to 72 h) or long periods (continuous acidification, 84 days). During short-term acidification, in all the experiments but one, there was a significant increase (up to 2.6 times as compared to the control) of the primary production and specific activity in the first 12 h, followed by a significant decrease and slow recovery from 48 h until the end of the experiment. If acidification is continuous, primary production and specific activity are significantly higher (between 10 to 15 times that of the control) in acidified channels, either with or without aluminum, by Day 33 and until the end. Biomass stayed constant or decreased in short-term acidification and increased (from 10 to 15 times) in continuous acidification.
TL;DR: Results suggest a right hemisphere competence in the categorization of both texture and shape information, and males showed better separation of categories for stimuli presented to both hands only.
TL;DR: This mechanism of cellular restriction of the virus by MHV3-activated macrophages from the resistant A/J strain appeared to be one of the sensitive targets for the suppressive action of dieldrin on host resistance.
01 Jan 1986
TL;DR: The problem of local realization of nonlinear systems by state-space is a classical problem in control theory as discussed by the authors, which has been completely solved by Kaiman [10] in the case of linear systems.
Abstract: Realization of nonlinear systems by state-space is a classical problem in control theory This problem has been completely solved by Kaiman [10] in the case of linear systems Similarly, it was solved for bilinear systems (see Brockett [2], d’Alessandro, Isidori, Ruberti [1], Fliess [3], Sussmann [12]) In the general case, let us mention the work of Sussmann [13], Hermann, Krener [7] and Jakubczyk [9]: they assume that the solutions are regular at any time and for any inputs This restriction lead Fliess to study local realization of nonlinear systems [5]
TL;DR: Good correlations were obtained for the immunomodulatory effects of selected pesticides, as measured by PFC and ELISA, which encourages support for the latter technique in the immunotoxicological screening of pesticides.
TL;DR: Chaetomiumcellulolyticum was able to produce xylanases on all the three lignocelluloses: wheat straw, corn stover and aspen wood.
Abstract: Chaetomium
cellulolyticum was able to produce xylanases on all the three lignocelluloses: wheat straw, corn stover and aspen wood. Wheat straw was the best. Solid state fermentation of lignocelluloses gave higher yields of xylanases than liquid state fermentation, but it took longer time of incubation.
TL;DR: In this article, the dependence of the protonation of neutral ammonia on the axial kinetic energy of protonated reactant ions has been studied in the gas phase, using various Protonated carbonyl compounds, inside the collision cell of a tandem quadrupole mass spectrometric system.
Abstract: The dependence of the protonation of neutral ammonia on the axial kinetic energy of protonated reactant ions has been studied in the gas phase, using various protonated carbonyl compounds, inside the collision cell of a tandem quadrupole mass spectrometric system. The hypothesis of two different and non-competitive reaction channels has been proposed. The first is characterized by a very low (peaked at ±0.05 eVcm) and well-defined axial kinetic energy of the reactant ion, while the second is more energy demanding (estimated threshold at ±0.2 eVcm) and expressed by a collisionally induced dissociation-like energy curve. Fourier transform mass spectrometric experiments have shown that ammonium ion can be generated by direct proton exchange and fragmentation of the adduct ion obtained.
TL;DR: Seymour's conjecture can be reduced to a conjecture about critical nonseparable graphs (in the sense of matching theory) and the latter conjecture is verified in the case of outerplanar graphs, thus proving that Seymour's conjecture holds for outerplanars graphs.