Abstract: The surface micro textures on the feet of the animals such as flies, geckos and tree frogs have been studied. According to the research result and the science of the bionic tribology, the bionic surfaces with the convex domes which possess the certain structural features are obtained. They can increase the friction coefficient. The increasing friction mechanism of the bionic surface with the convex domes is analyzed using the methods of theory analysis, simulation and experimental verification. The friction force between the bionic surface with the convex domes and the belt consists of the sliding friction force and the additional resistance resulting from the inlaying meshing effect. The contact transformation of the bionic surface with cylindrical convex domes and the belt is simulated by the software ANSYS. The increasing friction effect of the bionic surface with the cylindrical convex domes is verified by the experiments.
Abstract: Delamination is recognized as one of the most critical defects that can result from the machining composites. Delamination has been a major form of failure in drilled composite materials due to the composites lack of strength in the drilling direction, which results in poor surface finish, reduction in bearing strength, reduction in structural integrity and ultimately poor performance of the composite. Currently, most of the major research reported delamination address specific of machining fiber glass, graphite fiber or carbon fiber reinforced polymer composites. It is not yet clear how different drilling parameters affect the machinability of natural fiber reinforced polymer composite materials and quality of drilled holes. This paper report the investigation in drilling holes on natural fibre reinforced polyester composites and evaluate its hole quality by measuring delamination. Three different type of drill: twist 118o drill, brad drill and end mill were used. Drilling process is carried out for three spindle speed (1500 rpm, 2000 rpm and 2500 rpm) and three feed rate (0.1 mm/rev, 0.15 mm/rev and 0.2 mm/rev). Brad drill experienced higher delamination values compared to twist and end mill. Increasing of feed rate and spindle speed also caused a relevant increase in the delamination values. It is found that Rice husk reinforced polyester composites delamination value is lower when compared to the glass fiber reinforced polymer.
Abstract: In this paper, an element-free Galerkin method is presented to simulate the liquid metal flow in an open channel under external magnetic field. The global weak form of governing equations is obtained for the case of same size of the height of the liquid film and width of the open channel. Numerical simulations are carried out for some cases of liquid metal flow in an open channel. Results show that the element-free Galerkin method may steadily compute this kind of problem in some cases.
Abstract: Dynamic response of an electro-rheological sandwich beam subjected to simultaneous Impact loads will be considered. Analytical solution will be used to draw FRF diagram of the beam for different electric field. Upper and lower layers of the beam have different material properties. Coupled governing equations derived from Hamilton Principle will be solved in frequency domain to find transverse vibration of the beam.
Abstract: Based on the transmission line mode theory, designed one kind of small and dual band microstrip antenna on the magnetoelectric composite material. Then do the simulation by HFSS11.0 which based on the finite element method. The simulation results show that, when the return loss less than -10dB, antenna working in band 2360MHz~2500MHz and 3900MHz ~4200MHz, Compared with ordinary antenna, this antenna not only realizes the multi band, but also in the working frequency bandwidth compared to common antenna slightly raised, antenna size is reduced nearly 85%. Good impedance matching. This microstrip antenna has some value on the mobile device miniaturization for the miniaturization and dual band.
Abstract: Utilizing the Phase change material or PCM as thermal storage in solar research has been widely focused. Some researches embedded metal and non-metal Nanoparticles into the PCM to investigate the effect on the thermal properties of the mixtures. In this study, copper nanoparticles are dispersed into paraffin wax to form Nanoparticles-PCM mixture. Three samples have been prepared: Sample 1 is paraffin wax only, Sample 2 is 1% 20nm copper powder + 150 ml paraffin wax, and Sample 3 is 2% 20nm copper powder + 150 ml paraffin wax. Differential Scanning Calorimeter is used to analyse the melting point, solidification point and specific heat of mixture. Transmission Electron Microscopy is used to identify the shape and size of 20nm copper powder. The study showed that thermal conductivity of Nanoparticles-PCM mixture was increased as well as the sensible heat. However, there is reduction in the melting point and heat flow to melt the Nanomaterials but latent heat of fusion was increased. 20nm copper powder is proven to be suspended in the paraffin wax.
Abstract: Flexible formworks are dominantly used for concrete constructions. These constructions become rigid after curing and their form cannot be changed, also their color or translucency is stable during usage period; i.e. these constructions are not flexible. On the other hand, in order to satisfy new architectural requirements the necessity of flexibility and smartness is undeniable for the construction.The questions of this paper are: How smartness can be added to rigid structures? What are the roles of nano-flexible formworks to turn non-flexible structures into flexible ones? To answer the research questions, descriptive - analytical research method has been adopted and empirical data gathered to feed inference mechanism. Our investigation shows that if the flexible formwork has been made by smart materials which are changeable in nano-scale, and the formwork is left on the structure even after curing, it would act as a nano-flexible skin for the structure and would satisfy some architectural requirements in nano-scale.
Abstract: Perception of vision and motion is a vast interdisciplinary field combining psychology, neurology, physiology, mathematics, computer science, physics, philosophy and more. The issue of the actual mechanism for the visual and computational perception of motion in the human are keep grow for the last decade. Each of the researchers is keep pursuit to find the ideal potion of a robust recognition and detection for video system. Clutches by illumination and pose variations, several compensation techniques were proposed to overcome these issues. However, were successful for face recognition in partly lightened faces and not for facial expression recognition (FER). Attempts were made to implement FER. However these were not focused for intruder face recognition/monitoring. They lack the region of interest (ROI, in this case face detection) while processing, which is crucial for environment such as in a car (a possibility of another person behind/beside the driver). Thus, an Automated Video Surveillance system is presented in this paper. The system aims at tracking an object in motion and classifying it as a human or non-human entity, which would help in subsequent human activity analysis based on PCA based feature extraction.
Abstract: This article is focused on computational modeling of an interaction of malleable lumbar spine fixation device with ambient bone tissue focusing on solving problems of clinical practise. It describes creation of computational model including model of geometry, materials, loads and constraints. There is a comparative stress strain analysis of spinal segment after fixation device application with its physiological state. Computations are performed with use of FEM method. To simulate natural way of loading we used the compression of motional spinal segment. Results show the difference between the system including intervertebral disc in between vertebras and the system with applied lumbar spinal fixation device.
Abstract: These days most of the workers use hand controller tools. Because of this it is useful to know the relations between hand and these kinds of tools. One of these relations is cylindrical power grip. For this reason first of all a device is prepared for measuring the torque value. After that by creating a model in ANYBODY software for gripping motion for forces and muscular activities have been calculated. In this case for solving the inverse kinetic problem several cost functions are defined and the results are compared. On the other hand, by using Electromyography tests in gripping motion the activity of 3 surface muscles are investigated and finally the modeling and Electromyography’s results are compared.