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In the presented case study, the authors applied the multimethod approach utilising geophysical imaging with estimated uncertainty to the landslide in Cisiec, southwest Poland. Application of multiple geophysical methods such as electrical resistivity tomography (ERT), multichannel analysis of surface waves (MASW), refraction seismic method , ray-based seismic tomography , and reflection imaging was aimed at obtaining a detailed and high-resolution image of the subsurface. Drone-based digital terrain models (DTM) supported the subsurface imaging by providing a detailed view of the landslide surface. Accurate GPS-based geodesy conducted during data gathering was used to complete information about the topography of the area and correlate the results of geophysical surveys . The combination and transfer of information between methods allow solving multiple reflection imaging problems, especially lack of borehole information. The final result presents the detailed geophysical images of the landslide with a recognized depth of main slip surface ranging from 16 to 36 m. Because the study site is used as a ski slope, detailed information about the landslide structure is needed to provide safety for nearby construction. The methodology proposed in this paper can be used in similar case studies, where fast and cost-effective recognition of a landslide is required.

The presented work was realized within the framework of the AQUILO project, aiming in creating the base of knowledge for prospective future investments in offshore wind energy on Baltic Sea. The presented part of the work is focused on the experimental validation of numerical method of evaluation of the wave-induced forces on the bottom-mounted support structure of the offshore wind turbine. The experimental setup and measurement equipment, including in-house developed 6-DOF (six degree of freedom) dynamometer, are described. As a result, comparison of performance of different methods of evaluation of wave loads for wide range of parameters is presented. The results of experiments and numerical analyses are fairly consistent; largest discrepancy occurred at lowest wave frequencies, i.e. largest wave lengths. This may result from increased relative error of measurements for very long waves in relatively short tank.

The paper presents the results of numerical simulations of ship propeller operation bearing the name of Propeller Open Water (POW) Tests. The object of tests was a sample ship propeller (PPTC1), the geometrical and kinematic data of which are available, along with the results of model tests, on the official page of the research centre involved in the measurements. The research aimed at verifying the correctness of results of numerical simulations performed in the model and real scale. The results of numerical analyses performed in the model scale were confronted with those measured in the experiment. Then, making use of dimensionless coefficients which characterise propeller’s operation, the recorded model data were extrapolated to real conditions and compared with corresponding results of simulations. Both the numerical simulations and the experimental research were performed for the same propeller load states. The reported research is in line with other activities which aim at developing advanced numerical methods to support the process of ship propeller designing.

The standard propeller has been investigated in model scale, using medium size cavitation tunnel. The hydroacoustic characteristics of propellers under different loading conditions have been investigated. Additionally the presented experimental results have been used for the verification of applied numerical approach. During both numerical and experimental analyses non-uniform inflow propeller’s conditions have been adapted. Good correlations of both kinds of results have been noticed and highlighted.

Biomass of agricultural origin has the biggest potential from all kind of renewable energy sources in Poland because it provide continuous electricity generation, and is the only widespread source of renewable heat. In this paper an installation with a batch reactor was used to conductor experimental tests on three different energy plants by means of the torrefaction process: willow, Pennsylvanian mallow, and Jerusalem artichokes. Those energy plants were growing ion low-grade soils, which are abundant in Poland. Torrefaction or simply roasting of biomass is a thermal degradation of biomass structures by heating it a inert gas atmosphere like nitrogen under atmospheric pressure. This process removes low weight organic volatile components and moisture as well as depolymerises the long polysaccharide chains of biomass. To build up a demonstration plant for torrefaction process of energy crops plants the information concerning the specific temperature of caring the carbonization process for specific type of fuel and residence time should be provided in order to obtain the best C/H ratio in fuel, which is responsible for High Heating Value, carbonization level and best physico-chemical properties as a new fuel for energy production.

Engine intake systems should be carefully designed to provide a uniform flow to all cylinders. The current note presents the initial phase of the redesign process of an intake manifold of a four cylinder aircraft IC engine. By means of computational fluid dynamics analysis, the deficiency of the initial design in splitting the air flow among the runners is discovered, and an improvement of the original design is proposed. It is shown that a significant improvement in the flow distribution can be achieved by an appropriately installed guide vane, whereas the flow split is observed to be very sensitive to the geometry of the guide vane, necessitating a very careful design.

The article describes the research on the intake manifold for ultralight aircraft engine Vaxell 100i. It presents the actual and new redesigned manifold construction and points out the design requirements. The results of previously made numerical simulation of air flow inside the manifold are discussed. Computer analysis confirmed the appropriateness of internal guide vanes usage to improve the uniform air distribution between cylinders. For verification, a flow bench test stand was made for multicylinder intake manifold testing. A prototype manifold was built with the possibility of guide vane adjustment. The best variant had almost 5 times better uniformity of air distribution comparing to variant without the guide vane. Flow bench results confirmed the conclusions from numerical simulations.

In applications of augmented reality it is an essential task to retrieve the camera pose for correct overlay with virtual content. This can be realized by using a model-based camera tracking approach that fits a given model of the scene to the images captured by the camera. These systems have to be initialized properly for the pose estimation process of continuous tracking. We present a two-step concept for the global initialization of such model-based tracking systems. With a model database and known GPS coordinates as well as compass orientation, it is possible to determine which part of the scene is visible and to obtain a first rough pose. We also introduce a method to refine the initialization pose to overcome GPS inaccuracies. It has been successfully tested in an urban context.