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Cabri 3D is a software which connects geometry and algebra to enable measuring length, distance, area, angles, scalar product, volume and use them in calculations or in algebraic expressions. Cabri 3D gives new opportunities for teaching three-dimentional Euclidean geometry. In this work we describe some tools and functions of Cabri 3D. We also give a skech of using this mathematical software to create...
Image segmentation is an essential step in image processing. Many image segmentation methods are available but most of these methods are not suitable for noisy images or they require priori knowledge, such as knowledge on the type of noise. In order to overcome these obstacles, a new image segmentation algorithm is proposed by using a self-organizing map (SOM) with some changes in its structure and...
Flax fiber reinforced epoxy composites were subjected to water immersion tests in order to study the effects of water absorption on the mechanical properties. Epoxy composites specimens containing 0, 1, 5 and 10% fiber weight were prepared. Water absorption tests were conducted by immersing specimens in a deionized water bath at 25 °C and 90 °C for different time durations. The tensile and flexural...
In this study, stacking sequence optimization of composite beams with different layer thicknesses is investigated for various boundary conditions. A unified shear deformation theory is used for analytical solution. The optimization process is carried out in order to obtain the minimum deflection parameters for Clamped-Free (C-F), Clamped-Clamped (C-C) and simply supported (S-S) boundary conditions...
It is well-known that artificial neural networks have the ability to learn based on the provisions of new data. A special case of the so-called supervised learning is a mutual learning of two neural networks. This type of learning applied to a specific networks called Tree Parity Machines (abbreviated as TPM networks) leads to achieving consistent weight vectors in both of them. Such phenomenon is...
This paper presents conditions of forming products from titanium sheets by means of rubber stamping method. After introducing the issues connected with these elements manufacturing for aviation industry, considering standards and legal regulations, technological problems occurring during forming deep stiffening ribs. The results in the characteristic curvatures and distortion in the final products...
Adhesive joints may be used instead of forced-in joints, welded and riveted joints, soldered and twisted connections. They are characterized by a lot of advantages, thanks to them the adhesive joints are willingly used in manufacturing processes. These advantages include low price of joint, reduction of weight of the final construction, improvement of durability, reliability and quality and improving...
The paper presents the experimental investigation of the impact of velocity on drag force in the autogyro model. One of the methods which simulate motion of the flying object consists of using a wind tunnel. In this case, test object is stationary and the motion of air is forced by e.g. a special fan. The costs related with renting and the wind tunnel service are still very high. In this paper, the...
The paper presents a method, developed by the authors, for manufacturing polymer composites with the matrix manufactured in a layered manner (via 3D printing – Fused Deposition Modeling) out of a thermoplastic material. As an example of practical application of this method, functional prototypes are presented, which were used as elements of foundry tooling – patterns for sand molding. In case of manufacturing...
CMMs accuracy depend on a number of factors. In spite of using various methods for CMM correction, the differences can be observed in the metrological capability be¬tween the areas in the measuring volume of CMM. Authors attempted to estimate the impact of one of potential CMM accuracy influencing factors, a CMM Z-axis position during measurement, on measurement result. This article presents performed...
The paper presents functional relationships between surface geometry parameters, feedrate and vibrations level in the radial direction of the workpiece. Time characteristics of the acceleration of cutting tool vibration registered during C45 steel and stainless steel machining for separate axes (X, Y, Z) were presented as a function of feedrate f. During the tests surface geometric accuracy assessment...
Grinding is still an important method for surface finishing. At FPTM JEPU research, which deals with this issue is conducted. Experiments are carried out with grinding various materials under different conditions and then selected components of the surface integrity are evaluated. They include roughness Ra, Rm and Rz, Material ratio curve (Abbott Firestone curve) and also the obtained roundness. This...
Quality of service (QoS) is an important attribute for selecting a service during the service composition process. Although availability and reliability have been considered as the predominant factors for estimating reputation, two aspects are missing in the literature. First, their use is limited to composite service level and does not count on the atomic level. Second, their combined effect is not...
Carbon Nanotubes (CNTs) have a great potential in many areas like electromechanical systems, medical application, pharmaceutical industry etc. The surrounding physical environment of CNT is very important on torsional vibration behavior of CNT. Damp¬ing and elastic effect of medium to the torsional vibration of CNTs are investigated in the present study. Governing equation of motion of nanotube is...
Liquid metal when filling sand casting mould while pouring it out from ladle at the first moment comes across the sprue/gate system of the mould the purpose of which is to transfer liquid metal and feed the mould recess. The materials presently used for the elements of the sprue/gate systems are based on ceramics or the mixtures based on paper pulp. In this study the use of alternative mineral additions...
3D image technologies are widely recognized as the next generation of visual presentation considering the achievement of more natural experiences. To produce such images, two cameras are placed in a bit different position. When we seek to compress such images, we need a procedure to compress two images synchronously. In this paper, a procedure is presented for a suitable compression based on fractal...
This paper is primarily devoted to one of adhesive curing process parameters – pressure applied during curing, as well as the type of adhesive. The aim of this work is to determine the influence of pressure applied during curing process of aluminium alloy sheet adhesive joints on the strength of adhesive joints formed with two epoxy adhesives: Loctite 9484 and Loctite 9466. Three types of aluminium...
Safety of Mg milling processes can be expressed by means of the form and the number of fractions of chips formed during milling. This paper presents the state of the art of magnesium alloys milling technology in the aspect of chip fragmentation. Further-more, the impact of the depth of cut ap and the rake angle γ on the number of chip fractions was analysed in the study. These were conducted on AZ91HP...
In case of coordinate machines that use CAA correction matrix, the issue of kine¬matic errors analysis may be based on the determination of residual error distribu¬tion. Temperature changes have an impact on CMM kinematic structure, which may cause the differences in the map of residual errors. As for today, the residual errors were analysed only for the reference temperature. No research was undertaken...
Numerous experimental studies, including experiments performed by the authors, have shown that the part orientation during layer deposition has a very strong in-fluence on final strength of a product manufactured by additive Fused Deposition Technology. The paper presents the results of tensile, bending and impact strength tests performed on samples of various orientations, made out of ABS material...
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