Applied Mechanics and Materials Vol. 791

Abstract: The paper presents a methodology of building a mathematical model of dynamic system of shaft grinding under the condition of elastic strain, and the model itself. The model was worked out basing on analytical identification. The system of equations and general structural pattern of MM system of dynamic grinding are introduced. Such prepared system of equations and structural pattern of MM takes into account the geometry of machined layer and forces of cutting during the grinding, elastic properties of DS and the process of forming the section of the machined layer (ML). The specification of DS identifying for grinding the small stiffness shafts is shown.

Abstract: One of the requirements to the cabin of a forestry machine is the ability to absorb a certain amount of energy during deformation in the event of a rollover. The paper presents a method for increasing energy absorption of protective structure of a forestry machine cabin, enabling to reduce the risk of injuries to the operators in the event of an emergency. This is achieved by introducing into the structure of the protective frame of a cab energy-absorbing mounts in which the energy is absorbed due to plastic deformation of their elements in the event of a rollover of forestry machine. The article presents the design of the mount, describes the principle of its operation in the event of an emergency, and theoretical and experimental studies of the deformable mount. As the result of theoretical and experimental investigations the geometric parameters of the energy-absorbing mount are determined.

Abstract: The increasingly higher requirements of the contemporary industry contribute to the development of machining technologies, and also to the use of special jigs. The paper discusses, on the selected example, the process of designing and analyzing a special system for hydraulic clamping of simultaneously four castings to be machined on a modern CNC milling machine tool. Taking into account the possibility of a different solution to the formulated problem, two clamping system concepts are presented for making their comparison.

Abstract: In practice, worm surfaces are most often shaped as cone-derivative helical surfaces. Much less often, due to engineering difficulties, torus-derivative or other helical surfaces are used. Whereas, worms are most commonly machined with rotary tools by the hobbing method, whereby the tool action surface and the machined surface (being mutually enveloping) contact with each other over the entire profile height. In the case of the step-by-step method, the tool is a small-diameter finger mill, whose action surface is coupled with the surface being machined, thus it is an universal tool. As a result, it is possible to shape a helical surface with a preset arbitrary axial profile using the same tool. The machining is carried out in many passes on a CNC machine tool. The paper discusses the determination of the parameters of tool setting in the worm axial plane for the programming of a CNC machine tool.

Abstract: We present the results on the Karman vortex creations on the two circular cylinders. Changing the inlet velocity we examine static and dynamic pressure distributions. In such a configuration,a polymer piezoelectric foil, which could be placed inside turbulent boundary layers, can work as anenergy harvester. By matching the fluid flows predominant frequency with the natural frequency ofthe piezoelectric generator would maximize the piezoelectric power output.

Abstract: The paper presents the new flow equations of the cement dispersion, using different rheological models. The derived solutions are exact ones, obtained without previous approximations. The results of calculations carried out on the basis of the presented equations are compared to available literature data, obtained their good agreement.

Abstract: Hip replacement is one of the most commonly performed orthopedic procedures. The implant prosthesis is used in the treatment of lesions within the joint or damage caused by mechanical stress. The main factors are disease, that indication for arthroplasty include: rheumatoid arthritis, advanced degenerative changes, fractures proximal epiphysis of the femur and femoral head necrosis. The design elements of hip replacements and analysis of preclinical surgical implant mobilized towards the use of medical imaging techniques. It is this end, the patient qualified for arthroplasty are tested using one of the methods of radiological examination (X-ray), computed tomography (CT) or magnetic resonance imaging (MRI). The date obtained as a result of medical imaging are stored in the DICOM format ( Digital Imaging and Communications in Medicine). It is a standard established that create and exchange of medical images obtained as a result of various diagnostic methods. DICOM medical device obtains the information about the structure of data stored in a file or a sequence of files, and how to communicate with any device and program for their transfer. Contains data to interpret and process correctly the files, regardless of the equipment, that generated them. Additionally, it has the calibration information, which allows you to take measurements and calculations using the browser's [1].

Abstract: This paper presents the possibility of using advanced IT tools for the identification and analysis of biological signals on the example of electroencephalographic tests. Identification and numerical analysis of EEG signals from a person suffering from epilepsy during and between seizures is presented.

Abstract: In this paper, time-series pattern recognition is applied for a damage evaluation sequence represented by a frequency response change due to a damage coefficient occurrence. The objective of this paper is parameters tuning of pattern recognition system which discovers dependencies between data entries in time-series. The influence of input parameters over the ability of the immune algorithm to identify similarity of historical sequences describing frequency response change of an object (antibodies) as a result of a damage coefficient occurrence to a sequence describing frequency response with a noise due to external disturbances (pathogen) is researched. The investigated parameters are: affinity threshold At, suppression threshold St, number of mutated genes Nm, number of iterations Ino and number of clones K. Antibodies (sequences) belonging to a given neighborhood represent a given type of damage. Antibodies from the neighborhood undergo clonal selection and affinity maturation process to achieve better affinity to the pathogen. With the best matched antibody the type of damage in the problem of time-series pattern recognition is achieved.

Abstract: Designing process is such type of engineering activity that needs to link systemized engineering knowledge with non-systemized method of heuristic concepts generation. To obtain the more predictable results it is needed to change the heuristic elements into more systemized ones. One of possible solution is to use the integrative approach. It bases on the previously proposed structure of any technical mean and on the breakdown of designing activities according to analyzed constructional forms. The structure includes such subsystems of a technical mean like: structural one, drive one and control one. Whereas the distinguished constructional feature includes: geometric one, material one and assembly one. By proper joining the subsystems and constructional features it is possible to manage a designing process in the more effective way. In the paper is presented the formalized method of designing that utilizes mentioned integrative approach. The formalization allows conducting a designing process according the uniform set of rules. The proposed approach was applied for designing specific hydraulic systems. In the paper is presented its application for designing the new system of canopy movement for a mining mechanized support. The purpose of conducted project was to eliminate the unwanted movements of a canopy in the horizontal direction. Using the integrative approach it was possible to design the straight-line mechanism. It led to move a canopy only in the vertical direction. From the system point of view in this mechanism were eliminated the rotational kinematic pairs. Instead them it was used a sliding pair in a form of a square guides. The applied solution allows simplifying the construction of a support and also decreasing its weight. And this, in turns, leads to an increase of durability. From the perspective of the whole life-cycle of a mining support, as a specific technical mean, it results in significantly lower total costs.