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The commonly observed over prediction of aeolian saltation transport on sandy beaches is, at least in part, caused by saltation intermittency. To study small-scale saltation processes, high frequency saltation sensors are required on a high spatial resolution. Therefore, we developed a low-cost Saltation Detection System (SalDecS) with the aim to measure saltation intensity at a frequency of 10 Hz and with a spatial resolution of 0.10 m in wind-normal direction. Linearity and equal sensitivity of the saltation sensors were investigated during wind tunnel and field experiments. Wind tunnel experiments with a set of 7 SalDec sensors revealed that the variability of sensor sensitivity is at maximum 9% during relatively low saltation intensities. During more intense saltation the variability of sensor sensitivity decreases. A sigmoidal fit describes the relation between mass flux and sensor output measured during 5 different wind conditions. This indicates an increasing importance of sensor saturation with increasing mass flux. We developed a theoretical model to simulate and describe the effect of grain size, grain velocity and saltation intensity on sensor saturation. Time-averaged field measurements revealed sensitivity equality for 85 out of a set of 89 horizontally deployed SalDec sensors. On these larger timescales (hours) saltation variability imposed by morphological features, such as sand strips, can be recognized. We conclude that the SalDecS can be used to measure small-scale spatiotemporal variabilities of saltation intensity to investigate saltation characteristics related to wind turbulence.

Since the introduction of audio-oral and audio-visual methods in foreign language teaching, the necessity to develop oral comprehension and production has been systematically emphasized. This assertion finds its full justification in the postulate that one of the ultimate goals of foreign language teaching is to lead the learner towards an autonomous participation in oral communication which subsumes both production and comprehension. However, if one analyzes the didactic material used towards this objective, one is struck both by the disparities in the approaches, and the low degree of systematization. This tangible contrast between the objective and its realization leads us to raise the following questions: if communication is the central element, what is the elation holding between communicative competence on the one hand, and oral and written understanding and production on the other. If we limit ourselves to the level of understanding, does the variety in the didactic approach used imply that the approach is random or that it follows the identification of sub-objectives, necessary intermediate steps towards auntonomous understanding in the target language? ispartof: I.T.L., Review of Applied Linguistics vol:66 issue:4 pages:61-77 status: published

In this dissertation, I investigate the pluralization of presentational haber (e.g. Habian fiestas. `There were parties.') in the Spanish of Havana, Santo Domingo and San Juan. Drawing on Goldberg's (1995. Constructions: A construction grammar approach to argument structure. Chicago: Chicago University Press.) Cognitive Construction Grammar, I claim that the phenomenon consists in a language change from below: the pluralized variant of the presentational haber construction () is replacing the singular variant(). Using a mixed-effects logistic regression analysis, I show that speakers of the three Caribbean dialects pluralize the verb in 41-46% of the cases. The linguistic factors that were investigated in this study (typical action-chain position of the noun's referent, absence/presence of negation, verb tense, comprehension-to-production priming, and production-to-production priming) argue in favor of considering the variation as an argument-structure alternation. The comparative sociolinguistic analyses reveal that these factors have the same effect and relative strengths in the three varieties. Conditional inference trees show that the linguistic factors also display a similar pattern of interaction in Havana, Santo Domingo, and San Juan. This suggests that the variation is constrained by three general cognitive constraints on linguistic expression, namely, markedness of coding, statistical preemption, and structural priming. Haber pluralization also covaries with social factors. The results for gender and social class support that the phenomenon constitutes an advanced change from below. These results support the main hypothesis. These results illustrate that, with cognitive-linguistic theory, variationists can construct more adequate statistical models of linguistic alternations and derive stronger generalizations from them. nrpages: 234 status: published

This paper is concerned with the distinction between nuclear and non-nuclear grammatical relations in Nyulnyul, an effectively extinct language of Dampier Land, Western Australia. Drawing on research within Semiotic Grammar, it is proposed that a fundamental distinction needs to be drawn between experiential relations (Actor, Undergoer, Agent, and the like) and logical relations (circumstantial or adverbial elements). Although it is tempting to correlate nuclear and non-nuclear relations with the experiential-logical contrast, the relations are so unalike that it is misleading to place them on a single hierarchy. It is suggested instead that experiential grammatical relations can be meaningfully divided into nuclear and core types, and that this distinction provides a layered model for the clause as an experiential unit.