The paper concerns the evolution of village’s roofs from 18^th century to the present time. The study covers iconographic materials of 19^th century and is made on the basis of remaining and contemporary buildings. Ridge- and hip roofs of village huts and polish mansard roofs of church roofs is also pointed out. Examples of roofs of contemporary dwelling houses are given and their influence on the village landscape is described.

The subjects of the research are vibrations of thin plates on viscoelastic basis. Differential equations describing vibrations of a thin plate as well as those which describe viscoelastic basis have been solved by two methods: the finite elements method and the method of Zienkiewicz – Wood. In order to illustrate the correctness of proposed methodology of solution, a computer program has been created. The program was used for specific calculations for thin plates on viscoelastic basis and the analysis of the results was performed.

In the paper the problem of thermal conductivity in periodical layered composites is analyzed using the method of microlocal homogenisation [Woźniak 1987]. It is assumed that the temperature consists of two parts: macrotemperature and microtemperature The macrotemperature describes the distribution of the temperature in the body neglecting the influence of the body structure, the microtemperature includes the structure by including different thermophysical properties of the investigation layer. In the considered homogenised model the numerical analysis of the macrotemperature, the microlocal parameters, the parameters describing the thermophysical properties of the investigated body and the total temperature was conducted. The examples for two layered periodical bodies are calculated in this paper.

Shape of particles is one of the most fundamental physical properties of soil. It is defined by four parameters; sphericity, roundness, degree angularity of particles and roughness. Determination of every single factor influence on others physical and mechanical properties of soils is very difficult, but it can be summarised in one parameter. Up to now the roughness of particles was determined by some methods, but they are very difficult to be used in practice. A new method of roughness measurements is presented in this paper. Measurements of geometrical particles parameters are on photos from electronic scanning microscope. On the photo the length of particle contour, and length of polygon circumscribed on particle was measured with planimeter. In this method the area of polygon circumscribed on particle and area particle shape on the photo are the same. The results are used for calculation of asperity index I_a (equation 3). The experimental part of this method was realised on photos of about 150 particles of several soils, which shapes and roughness were very differentiated. The theoretically analysis of asperity index determined for imagined surface is based on assumption, that roughness of the surface is composed only with triangles, semiculars, or only with trapezoides forms (fig. 4). The value of maximal asperity index calculated for simplified shape very near to the maximal value I_a obtained for real shape of fly ash particle.

Permeability proprieties of soils play fundamental role in design calculation of earth structure. Geotechnical parameter which describe these proprieties is permeability coefficient. The paper contains an analysis of testing procedure for determination of permeability coefficient in a horizontal direction in cohesive soils from BAT probe. In this paper the results of in situ coefficient k_hBAT in the havily overconsolidated clays Warsaw region have been presented. In the elaborated empirical formulae the coefficient was determined on the basis of calibration BAT probe and laboratory test results obtained from constant flow rate permeability tests (Flow Pump technique). Comparision of field and laboratory tests results gives the possibility to elaborate method for in situ measurement of coefficient k_hBAT by BAT probe. Analysis of factors influence on correct estimation flow water parameters in pliocene clays shown the variation of k_h coefficients at depth in the subsoil geological profile in Warsaw.

The paper concerns the use of microwave oven in determination of water content in soils. Major advantages of microwave oven based method consist in easy access to the equipment and its low cost (around 75–100 €). Besides the method is relatively quick (2–5 minutes). The tests results presented in the paper were obtained on the basis of 19 representative cohesive and cohesionless soils. For each soil water, content was determined in the wide range of its state: from air-dry to liquid state. The carried out tests made possible to obtain very good correlation between water content determined in standard oven and microwave oven methods. In conclusion some hints concerning test procedure were given which might be helpful in its wide application in geotechnical laboratory at site.

The aim of study was to estimate and discuss the maximum number of the realization dates of task and of all tasks contained in a network schedule time – limit. In this paper was considered task realization without any breaks as well as with division into two stages. Worked out formula was used to analyse very simple network schedule created from six tasks. In the second part of article it was proved that the number of possible task structures in the whole schedule depends mostly on the deadline realization time of enterprise, whole time slack in each task and on the number of all tasks in chart schedule. Obtained results have basic meaning while looking for an algorithm of resource analysis which enables to connect for all task start and end dates with available sources. Properly constructions and analysis of network schedule is necessary to create an effective project plan while keeping various technologic and organization conditions.

The ecophysiographic study is a new element of the Polish spatial planning system introduced in the 1^st of January 2001. The article presents evaluation of topoclimate and bioclimate as part of the ecophysiographic study. The highest biotopoclimatic differentiation in Łuk Siekierkowski area has been found between an agricultural area and urban area. In case of appropriation this rural area for housing sparsely building making good conditions of ventilation are recommended. In case of appropriation this area for industry additional specialistic elaboration is necessary.

The term of mean distance L was widened for its various aspects in case of expanses P of any border configuration and of any position of industrial and/or commercial centre G. By selecting p(x, y) skilfully, the quality of soils, various plant covers, vertical differentiation as well as various technological obstacles in the expanse under investigation can be taken into consideration:
where
The calculations can be performed under computer control. To check the quality of spatial development and to compare various expanses, an expanse shape coefficient U defined by a relation of U = L/L_nm is introduced, L_nm being the shortest of the mean distances, which can be obtained in the expanse under investigation:
the shortest.
The shape coefficient U determined in such a way lets us know what amount of labour above that necessary has been done due to the position of existing industrial and/or commercial centre that is not the best with respect to the expanse.

The study presents the description of the loss of stability and problems associated with the determination of energy-consumption in plastic states of thickset, thin-walled and sandwich, cylindrical axially crushed rods. The author analysed the course of rod deformation depending on the applied load using a simultaneous, divided screen filming technique. The obtained theoretical results were compared with experimental results of thin-walled rods made of steel St35 (DIN 2391-67).