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Experimental and Numerical Analysis of Compression Thin-Walled Composite Plates Weakened by Cut-Outs

. Debski, H.; Sadowski, T., “Modelling of microcracks initiation and evolution along interfaces of the WC/Co composite by the finite element method:, COMPUTATIONAL MATERIALS SCIENCE 83: 403-411, 2014. 6. Falkowicz K., Debski H. “Postbuckling Behaviour of Laminated Plates with a Cut-Out”, ADVANCES IN SCIENCE AND TECHNOLOGY RESEARCH JOURNAL 11(1): 186-193, 2017. 7. Falkowicz K., Debski H. “Numerical and Experimental Analysis of Compression Plate with Cut-Out”, Mechanics and Mechanical Engineering 20(2): 167-175, 2016. 8. Falkowicz, K., Ferdynus, M

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Mode frequency analysis of antisymmetric angle-ply laminated composite stiffened hypar shell with cutout

1 Introduction Laminated composite shells now constitute a large percentage of structures including aerospace, marine, and automotive structural components. Structural engineers have already picked up laminated composite hypar shells (hyperbolic paraboloid bounded by straight edges) as roofing units because these can cover large column-free areas with reduced dead weight. This class of shells has only the radius of cross curvature that is unique to this shell form. Roof structures are sometimes provided with cutout to allow the entry of light, venting and

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Qualitative analysis of irregular fields delivered with dual electron multileaf collimator: A Monte Carlo study

Abstract

The use of a dual electron multileaf collimator (eMLC) to collimate therapeutic electron beam without the use of cutouts has been previously shown to be feasible. Further Monte Carlo simulations were performed in this study to verify the nature and appearance of the isodose distribution in water phantom of irregular electron beams delivered by the eMLC. Electron fields used in this study were selected to reflect those used in electron beam therapy. Results of this study show that the isodose distribution in a water phantom obtained from the simulation of irregular electron beams through the eMLC conforms to the pattern of the eMLC used in the delivery of the beam. It is therefore concluded that the dual eMLC could deliver isodose distributions reflecting the pattern of the eMLC field that was used in the delivery of the beam.

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Seismic Performance Of A Precast Reinforced Concrete Wall With Cut-Out Opening Retrofitted Using Carbon Fibre Strips

, El Maaddawy T, Sherif S., 2009. FRP composites for shear strengthening of reinforced concrete deep beams with openings. Compos Struct 89:60–9. Enochsson O, Lundqvist J, Taljsten B, Rusinowski P, Olofsson T., 2007. CFRP strengthened openings in two-way concrete slabs – an experimental and numerical study. Constr Build Mater, 21:810–26. Florut S-C, Sas G, Popescu C, Stoian V., 2014. Tests on reinforced concrete slabs with cut-out openings strengthened with fibre-reinforced polymers. Compos Part B – Eng, 66:484–93. Ganesan, N., Abraham, R., Beena, P

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Dynamical Analysis of Stiffened Plates under Patch Loading

References Ali R. and Atwal S.J. (1980): Prediction of natural frequencies of rectangular plates with rectangular cutouts . - Computer and Structures, vol.12, pp.819-823. Corr R.B. and Jennings A.A. (1976): Simultaneous iteration for symmetric eigen value problem. - Int. Journal of Numerical Method Engng., vol.10, pp.647-663. Dickinson S.M. and Kalidas M.M. (1981): Vibration and buckling calculation for rectangular plates subjected to complicated in-plane stress distribution by using numerical

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Compensating Pose Uncertainties through Appropriate Gripper Finger Cutouts

Abstract

The gripper finger design is a recurring problem in many robotic grasping platforms used in industry. The task of switching the gripper configuration to accommodate for a new batch of objects typically requires engineering expertise, and is a lengthy and costly iterative trial-and-error process. One of the open challenges is the need for the gripper to compensate for uncertainties inherent to the workcell, e.g. due to errors in calibration, inaccurate pose estimation from the vision system, or object deformation. In this paper, we present an analysis of gripper uncertainty compensating capabilities in a sample industrial object grasping scenario for a finger that was designed using an automated simulation-based geometry optimization method (Wolniakowski et al., 2013, 2015). We test the developed gripper with a set of grasps subjected to structured perturbation in a simulation environment and in the real-world setting. We provide a comparison of the data obtained by using both of these approaches. We argue that the strong correspondence observed in results validates the use of dynamic simulation for the gripper finger design and optimization.

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Influence of RC Element Wiring in Electrical Circuit on Electromechanical Thermostat Contact Wear

Abstract

Contact wear caused by electric arc during electric contact make (cut-in) and break (cut-out) has the direct impact on the contact lifetime. The RC element wired parallelly to the contact will eliminate or reduce the arcing and subsequently extend the lifetime. Comparative tests of the two sets of identical Danfoss 077B electromechanical thermostats have been carried out. In the first batch, standard thermostats were tested. In the second batch, the same thermostat types, but with RC elements wired parallel to thermostats main contacts were tested. Measurement has not proven any improvement of the contact wear. Temperature drift and change of the critical dimension caused by contact wear were very similar in the both cases. Thus, the application of RC element is considered not reasonable measure for reduction of contact wear of electromechanical thermostats.

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Technology of Producing the Contact Connections of Superconductor Metal-Sheathed Cable

Abstract

The technology of producing the current contact connections on the superconductor cable edges is presented. This lead cable is used as one of the major elements of the magnetic system in thermonuclear reactor construction, actuality for modern world energy. The technology is realized by the radial draft of metal thin-walled tube on the conductor’s package. The filling of various profiles by round section wire is optimized. Geometrical characteristics of the dangerous crosssection (as a broken ring) of thin-walled tube injured by the sector cut-out are accounted. The comparative strength calculation of the solid and injured tubes at a longitudinal compression and lateral bending is acted. The radial draft mechanism of cylindrical thin-walled sheath with the wire packing is designed. The necessity to use the nonlinear theory for the sheaths calculate is set. The resilient co-operation of wires as the parallel located cylinders with the contact stripes of rectangular form is considered.

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Mechanical Studies of Injection Molded Composites with Polypropilene Matrix

Abstract

The wide use of composite materials is mainly due to their excellent strength / mass ratio, corrosion resistance and relatively low price. Approximately 35-40% of the fibre-reinforced composites are made of thermoplastic polymers in which fibreglass, carbon or natural fibres are most often used as reinforcement, while the remaining 60 – 65% is made up of high-tech carbon or glass fibre-reinforced thermosetting composites. Most of them are used in the transport and electronics industries. New processing technologies not only improve the properties of the products but also contribute to reducing costs.

In this paper, we compare the results of mechanical tests with molded standard specimens with polypropylene matrix and test results from cut-outs from injection molded products.

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Rules for folding polyminoes from one level to two levels

Abstract

Polyominoes have been the focus of many recreational and research investigations. In this article, the authors investigate whether a paper cutout of a polyomino can be folded to produce a second polyomino in the same shape as the original, but now with two layers of paper. For the folding, only “corner folds” and “half edge cuts” are allowed, unless the polyomino forms a closed loop, in which case one is allowed to completely cut two squares in the polyomino apart. With this set of allowable moves, the authors present algorithms for folding different types of polyominoes and prove that certain polyominoes can successfully be folded to two layers. The authors also establish that other polyominoes cannot be folded to two layers if only these moves are allowed.

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