This study aimed to indicate the variability range of parameter values describing the geomechanical properties of Carboniferous rocks depending on the moisture content of the laboratory sample. We assumed that the moisture content in the tested rock samples corresponds to various water saturation states in the rock mass. The states could be caused by complete and long-term drainage, water inflow, or the position of the rock sample to the ventilation ducts or the water table in flooded mine workings. In line with this assumption, measurements were made on samples of accompanying rock using two water saturation states of rock pores – moisture of samples, i.e., air-dried and capillary saturation states. Laboratory surveys were also made for the state of moisture of the coals obtained in the process of immersion of the sample in water. The air-dried state of rocks as standard in geomechanical tests in laboratories was compared with the surroundings of mining excavations, mostly ventilated ones, located within a long-term preserved depression cone, especially in hydrogeological covered areas. We used the capillary saturation state to demonstrate significant changes in the values of basic geomechanical parameters under the influence of the water from the surface and higher aquifers, circulating in the rock mass near groundwater reservoirs. Capillary saturation was the closest to natural moisture in the rock mass drained from free water. The coefficient of changes in the geomechanical properties of rocks associated with the change in moisture content and the transition of rocks from the air-dried state to the capillary saturation state was determined. The parameter was suitable for simulating probable changes in the values of geomechanical parameters of rocks and approximating the laboratory moisture content to the conditions occurring in the rock mass. Linear relationships were also developed with very good or good, and sometimes satisfactory coefficient determinations.

This article deals with the study of Gulf Arabic. By the means of the Qatari Arabic Corpus elaborated by Elmahdy et al. (2014), the aim of this study is investigating a number of selected verbal prefixes and the active participle gāʕid ‘sitting’ as a progressive aspect marker in Qatari Arabic, a relatively under researched variety in the field of Arabic Dialectology. A descriptive and quantitative approach in the data collection was adopted and the validation process, throughout the whole corpus which consists of 15 hours of speech flow, provided over 600 manually-selected tokens of verbal prefixes and active participles as progressive aspect markers whose main forms and functions were discussed in the paper.

The purpose of the present research relates to the sensitivity analysis of road vehicle comfort and handling performances with respect to suspension technological parameters. The envisaged suspension being of semi-active nature, this implies first to consider an hybrid modeling approach consisting of a 3D multibody model of the full car - an Audi A6 in our case - coupled with the electro-hydraulic model of the suspension dampers. Concerning parameter sensitivitie, the goal is to capture them for themselves - and not necessarily for optimization purpose - because their knowledge is of a great interest for the damper manufacturer.

An important issue of the research is to consider objective functions which are based on complete time integrations along a given trajectory, the goal being - for instance - to quantify the sensitivity of the carbody rms acceleration (comfort) or of the vehicle overturning character (handling) with respect to suspension parameters. On one hand, the accuracy of the various partial derivatives computation can be greatly enhanced thanks to the symbolic capabilities of our ROBOTRAN multibody program. On the other hand, the computational efficiency of the process also takes advantage of the recursive formulation of the multibody equations of motion which must be time integrated with respect to both the generalized coordinates and their partial derivatives in case of the so-called direct method underlying sensitivity analysis.