Search results for: and NODE displacement
691 Material Failure Process Simulation by Improved Finite Elements with Embedded Discontinuities
Authors: Gelacio Juárez-Luna, Gustavo Ayala, Jaime Retama-Velasco
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This paper shows the advantages of the material failure process simulation by improve finite elements with embedded discontinuities, using a new definition of traction vector, dependent on the discontinuity length and the angle. Particularly, two families of this kind of elements are compared: kinematically optimal symmetric and statically and kinematically optimal non-symmetric. The constitutive model to describe the behavior of the material in the symmetric formulation is a traction-displacement jump relationship equipped with softening after reaching the failure surface. To show the validity of this symmetric formulation, representative numerical examples illustrating the performance of the proposed formulation are presented. It is shown that the non-symmetric family may over or underestimate the energy required to create a discontinuity, as this effect is related with the total length of the discontinuity, fact that is not noticed when the discontinuity path is a straight line.Keywords: variational formulation, strong discontinuity, embedded discontinuities, strain localization
Procedia PDF Downloads 781690 Design and Fabrication of an Array Microejector Driven by a Shear-Mode Piezoelectric Actuator
Authors: Chiang-Ho Cheng, Hong-Yih Cheng, An-Shik Yang, Tung-Hsun Hsu
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This paper reports a novel actuating design that uses the shear deformation of a piezoelectric actuator to deflect a bulge-diaphragm for driving an array microdroplet ejector. In essence, we employed a circular-shaped actuator poled radial direction with remnant polarization normal to the actuating electric field for inducing the piezoelectric shear effect. The array microdroplet ejector consists of a shear type piezoelectric actuator, a vibration plate, two chamber plates, two channel plates and a nozzle plate. The vibration, chamber and nozzle plate components are fabricated using nickel electroforming technology, whereas the channel plate is fabricated by etching of stainless steel. The diaphragm displacement was measured by the laser two-dimensional scanning vibrometer. The ejected droplets of the microejector were also observed via an optic visualization system.Keywords: actuator, nozzle, microejector, piezoelectric
Procedia PDF Downloads 427689 A New DIDS Design Based on a Combination Feature Selection Approach
Authors: Adel Sabry Eesa, Adnan Mohsin Abdulazeez Brifcani, Zeynep Orman
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Feature selection has been used in many fields such as classification, data mining and object recognition and proven to be effective for removing irrelevant and redundant features from the original data set. In this paper, a new design of distributed intrusion detection system using a combination feature selection model based on bees and decision tree. Bees algorithm is used as the search strategy to find the optimal subset of features, whereas decision tree is used as a judgment for the selected features. Both the produced features and the generated rules are used by Decision Making Mobile Agent to decide whether there is an attack or not in the networks. Decision Making Mobile Agent will migrate through the networks, moving from node to another, if it found that there is an attack on one of the nodes, it then alerts the user through User Interface Agent or takes some action through Action Mobile Agent. The KDD Cup 99 data set is used to test the effectiveness of the proposed system. The results show that even if only four features are used, the proposed system gives a better performance when it is compared with the obtained results using all 41 features.Keywords: distributed intrusion detection system, mobile agent, feature selection, bees algorithm, decision tree
Procedia PDF Downloads 408688 Creep Effect on Composite Beam with Perfect Steel-Concrete Connection
Authors: Souici Abdelaziz, Tehami Mohamed, Rahal Nacer, Said Mohamed Bekkouche, Berthet Jean-Fabien
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In this paper, the influence of the concrete slab creep on the initial deformability of a bent composite beam is modelled. This deformability depends on the rate of creep. This means the rise in value of the longitudinal strain ε c(x,t), the displacement D eflec(x,t) and the strain energy E(t). The variation of these three parameters can easily affect negatively the good appearance and the serviceability of the structure. Therefore, an analytical approach is designed to control the status of the deformability of the beam at the instant t. This approach is based on the Boltzmann’s superposition principle and very particularly on the irreversible law of deformation. For this, two conditions of compatibility and two other static equilibrium equations are adopted. The two first conditions are set according to the rheological equation of Dischinger. After having done a mathematical arrangement, we have reached a system of two differential equations whose integration allows to find the mathematical expression of each generalized internal force in terms of the ability of the concrete slab to creep.Keywords: composite section, concrete, creep, deformation, differential equation, time
Procedia PDF Downloads 383687 Numerical Investigation of Seismic Behaviour of Building
Authors: Tinebeb Tefera Ashene
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Glass facade systems have gained popularity in recent times. During an earthquake, building frames suffer large inter-story drifts, causing racking of building facade systems. A facade system is highly vulnerable and fails more frequently than a building with significant devastating effects. The usage of Metallic yield damper connections (Added Damping Stiffness) is proposed in this study to mitigate the aforementioned problems. Results showed as compared to control, usage of Metallic yield damper connections (Added-Damping-And-Stiffness) exhibited a reduction of connection deformation and axial force; differential displacement between frame and facade; and facade distortion by 44.35%, 43.33%, and 51.45% respectively. Also, employing proposed energy-absorbing connections reduced inter-story link joint drift by 71.11% and mitigated detrimental seismic effects on the entire building facade system.Keywords: damper, energy dissipation, metallic yield, facades
Procedia PDF Downloads 53686 Autism Spectrum Disorder Classification Algorithm Using Multimodal Data Based on Graph Convolutional Network
Authors: Yuntao Liu, Lei Wang, Haoran Xia
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Machine learning has shown extensive applications in the development of classification models for autism spectrum disorder (ASD) using neural image data. This paper proposes a fusion multi-modal classification network based on a graph neural network. First, the brain is segmented into 116 regions of interest using a medical segmentation template (AAL, Anatomical Automatic Labeling). The image features of sMRI and the signal features of fMRI are extracted, which build the node and edge embedding representations of the brain map. Then, we construct a dynamically updated brain map neural network and propose a method based on a dynamic brain map adjacency matrix update mechanism and learnable graph to further improve the accuracy of autism diagnosis and recognition results. Based on the Autism Brain Imaging Data Exchange I dataset(ABIDE I), we reached a prediction accuracy of 74% between ASD and TD subjects. Besides, to study the biomarkers that can help doctors analyze diseases and interpretability, we used the features by extracting the top five maximum and minimum ROI weights. This work provides a meaningful way for brain disorder identification.Keywords: autism spectrum disorder, brain map, supervised machine learning, graph network, multimodal data, model interpretability
Procedia PDF Downloads 67685 A Virtual Grid Based Energy Efficient Data Gathering Scheme for Heterogeneous Sensor Networks
Authors: Siddhartha Chauhan, Nitin Kumar Kotania
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Traditional Wireless Sensor Networks (WSNs) generally use static sinks to collect data from the sensor nodes via multiple forwarding. Therefore, network suffers with some problems like long message relay time, bottle neck problem which reduces the performance of the network. Many approaches have been proposed to prevent this problem with the help of mobile sink to collect the data from the sensor nodes, but these approaches still suffer from the buffer overflow problem due to limited memory size of sensor nodes. This paper proposes an energy efficient scheme for data gathering which overcomes the buffer overflow problem. The proposed scheme creates virtual grid structure of heterogeneous nodes. Scheme has been designed for sensor nodes having variable sensing rate. Every node finds out its buffer overflow time and on the basis of this cluster heads are elected. A controlled traversing approach is used by the proposed scheme in order to transmit data to sink. The effectiveness of the proposed scheme is verified by simulation.Keywords: buffer overflow problem, mobile sink, virtual grid, wireless sensor networks
Procedia PDF Downloads 391684 Process Safety Evaluation of a Nuclear Power Plant through Virtual Process Hazard Analysis Using Hazard and Operability Technique
Authors: Elysa V. Largo, Lormaine Anne A. Branzuela, Julie Marisol D. Pagalilauan, Neil C. Concibido, Monet Concepcion M. Detras
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The energy demand in the country is increasing; thus, nuclear energy is recently mandated to add to the energy mix. The Philippines has the Bataan Nuclear Power Plant (BNPP), which can be a source of nuclear energy; however, it has not been operated since the completion of its construction. Thus, evaluating the safety of BNPP is vital. This study explored the possible deviations that may occur in the operation of a nuclear power plant with a pressurized water reactor, which is similar to BNPP, through a virtual process hazard analysis (PHA) using the hazard and operability (HAZOP) technique. Temperature, pressure, and flow were used as parameters. A total of 86 causes of various deviations were identified, wherein the primary system and line from reactor coolant pump to reactor vessel are the most critical system and node, respectively. A total of 348 scenarios were determined. The critical events are radioactive leaks due to nuclear meltdown and sump overflow that could lead to multiple worker fatalities, one or more public fatalities, and environmental remediation. There were existing safeguards identified; however, further recommendations were provided to have additional and supplemental barriers to reduce the risk.Keywords: PSM, PHA, HAZOP, nuclear power plant
Procedia PDF Downloads 154683 Optimal Design of Composite Cylindrical Shell Based on Nonlinear Finite Element Analysis
Authors: Haider M. Alsaeq
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The present research is an attempt to figure out the best configuration of composite cylindrical shells of the sandwich type, i.e. the lightest design of such shells required to sustain a certain load over a certain area. The optimization is based on elastic-plastic geometrically nonlinear incremental-iterative finite element analysis. The nine-node degenerated curved shell element is used in which five degrees of freedom are specified at each nodal point, with a layered model. The formulation of the geometrical nonlinearity problem is carried out using the well-known total Lagrangian principle. For the structural optimization problem, which is dealt with as a constrained nonlinear optimization, the so-called Modified Hooke and Jeeves method is employed by considering the weight of the shell as the objective function with stress and geometrical constraints. It was concluded that the optimum design of composite sandwich cylindrical shell that have a rigid polyurethane foam core and steel facing occurs when the area covered by the shell becomes almost square with a ratio of core thickness to facing thickness lies between 45 and 49, while the optimum height to length ration varies from 0.03 to 0.08 depending on the aspect ratio of the shell and its boundary conditions.Keywords: composite structure, cylindrical shell, optimization, non-linear analysis, finite element
Procedia PDF Downloads 391682 Biosurfactants Produced by Antarctic Bacteria with Hydrocarbon Cleaning Activity
Authors: Claudio Lamilla, Misael Riquelme, Victoria Saez, Fernanda Sepulveda, Monica Pavez, Leticia Barrientos
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Biosurfactants are compounds synthesized by microorganisms that show various chemical structures, including glycolipids, lipopeptides, polysaccharide-protein complex, phospholipids, and fatty acids. These molecules have attracted attention in recent years due to the amphipathic nature of these compounds, which allows their application in various activities related to emulsification, foaming, detergency, wetting, dispersion and solubilization of hydrophobic compounds. Microorganisms that produce biosurfactants are ubiquitous, not only present in water, soil, and sediments but in extreme conditions of pH, salinity or temperature such as those present in Antarctic ecosystems. Due to this, it is of interest to study biosurfactants producing bacterial strains isolated from Antarctic environments, with the potential to be used in various biotechnological processes. The objective of this research was to characterize biosurfactants produced by bacterial strains isolated from Antarctic environments, with potential use in biotechnological processes for the cleaning of sites contaminated with hydrocarbons. The samples were collected from soils and sediments in the South Shetland Islands and the Antarctic Peninsula, during the Antarctic Research Expedition INACH 2016, from both pristine and human occupied areas (influenced). The bacteria isolation was performed from solid R2A, M1 and LB media. The selection of strains producing biosurfactants was done by hemolysis test on blood agar plates (5%) and blue agar (CTAB). From 280 isolates, it was determined that 10 bacterial strains produced biosurfactants after stimulation with different carbon sources. 16S rDNA taxonomic markers, using the universal primers 27F-1492R, were used to identify these bacterias. Biosurfactants production was carried out in 250 ml flasks using Bushnell Hass liquid culture medium enriched with different carbon sources (olive oil, glucose, glycerol, and hexadecane) during seven days under constant stirring at 20°C. Each cell-free supernatant was characterized by physicochemical parameters including drop collapse, emulsification and oil displacement, as well as stability at different temperatures, salinity, and pH. In addition, the surface tension of each supernatant was quantified using a tensiometer. The strains with the highest activity were selected, and the production of biosurfactants was stimulated in six liters of culture medium. Biosurfactants were extracted from the supernatants with chloroform methanol (2:1). These biosurfactants were tested against crude oil and motor oil, to evaluate their displacement activity (detergency). The characterization by physicochemical properties of 10 supernatants showed that 80% of them produced the drop collapse, 60% had stability at different temperatures, and 90% had detergency activity in motor and olive oil. The biosurfactants obtained from two bacterial strains showed a high activity of dispersion of crude oil and motor oil with halos superior to 10 cm. We can conclude that bacteria isolated from Antarctic soils and sediments provide biological material of high quality for the production of biosurfactants, with potential applications in the biotechnological industry, especially in hydrocarbons -contaminated areas such as petroleum.Keywords: antarctic, bacteria, biosurfactants, hydrocarbons
Procedia PDF Downloads 279681 Settlement Performance of Soft Clay Reinforced with Granular Columns
Authors: Muneerah Jeludin, V. Sivakumar
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Numerous laboratory-based research studies on the behavior of ground improved with granular columns with respect to bearing capacity have been well-documented. However, information on its settlement performance is still scarce. Laboratory model study on the settlement behavior of soft clay reinforced with granular columns was conducted and results are presented. The investigation uses a soft kaolin clay sample of 300 mm in diameter and 400 mm in length. The clay samples were reinforced with single and multiple granular columns of various lengths using the displacement and replacement installation method. The results indicated that that no settlement reduction was achieved for a short single floating column. The settlement reduction factors reported for L/d ratios of 5.0, 7.5 and 10.0 are in the range of 1 to 2. The findings obtained in this research showed that the reduction factors are considerably less and that load-sharing mechanism between columns and surrounding clay is complex, particularly for column groups and is affected by other factors such as negative skin friction.Keywords: ground improvement, model test, reinforced soil, settlement
Procedia PDF Downloads 466680 FZP Design Considering Spherical Wave Incidence
Authors: Sergio Pérez-López, Daniel Tarrazó-Serrano, José M. Fuster, Pilar Candelas, Constanza Rubio
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Fresnel Zone Plates (FZPs) are widely used in many areas, such as optics, microwaves or acoustics. On the design of FZPs, plane wave incidence is typically considered, but that is not usually the case in ultrasounds, especially in applications where a piston emitter is placed at a certain distance from the lens. In these cases, having control of the focal distance is very important, and with the usual Fresnel equation a focal displacement from the theoretical distance is observed due to the plane wave supposition. In this work, a comparison between FZP with plane wave incidence design and FZP with point source design in the case of piston emitter is presented. Influence of the main parameters of the piston in the final focalization profile has been studied. Numerical models and experimental results are shown, and they prove that when spherical wave incidence is considered for the piston case, it is possible to have a fine control of the focal distance in comparison with the classical design method.Keywords: focusing, Fresnel zone plates, FZP, ultrasound
Procedia PDF Downloads 253679 Concrete Cracking Simulation Using Vector Form Intrinsic Finite Element Method
Authors: R. Z. Wang, B. C. Lin, C. H. Huang
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This study proposes a new method to simulate the crack propagation under mode-I loading using Vector Form Intrinsic Finite Element (VFIFE) method. A new idea which is expected to combine both VFIFE and J-integral is proposed to calculate the stress density factor as the crack critical in elastic crack. The procedure of implement the cohesive crack propagation in VFIFE based on the fictitious crack model is also proposed. In VFIFIE, the structure deformation is described by numbers of particles instead of elements. The strain energy density and the derivatives of the displacement vector of every particle is introduced to calculate the J-integral as the integral path is discrete by particles. The particle on the crack tip separated into two particles once the stress on the crack tip satisfied with the crack critical and then the crack tip propagates to the next particle. The internal force and the cohesive force is applied to the particles.Keywords: VFIFE, crack propagation, fictitious crack model, crack critical
Procedia PDF Downloads 335678 Equal Channel Angular Pressing of Al1050 Sheets: Experimental and Finite Element Survey
Authors: P. M. Keshtiban, M. Zdshakoyan, G. Faragi
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Different severe plastic deformation (SPD) methods are the most successful ways to build nano-structural materials from coarse grain samples without changing the cross-sectional area. One of the most widely used methods in the SPD process is equal channel angler pressing (ECAP). In this paper, ECAP process on Al1050 sheets was evaluated at room temperature by both experiments and finite element method. Since, one of the main objectives of SPD processes is to achieve high equivalent plastic strain (PEEQ) in one cycle, the values of PEEQ obtained by finite element simulation. Also, force-displacement curve achieved by FEM. To study the changes of mechanical properties, micro-hardness tests were conducted on samples and improvement in the mechanical properties were investigated. Results show that there is the good proportion between FEM, theory and experimental results.Keywords: AL1050, experiments, finite element method, severe plastic deformation
Procedia PDF Downloads 420677 Signal Strength Based Multipath Routing for Mobile Ad Hoc Networks
Authors: Chothmal
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In this paper, we present a route discovery process which uses the signal strength on a link as a parameter of its inclusion in the route discovery method. The proposed signal-to-interference and noise ratio (SINR) based multipath reactive routing protocol is named as SINR-MP protocol. The proposed SINR-MP routing protocols has two following two features: a) SINR-MP protocol selects routes based on the SINR of the links during the route discovery process therefore it select the routes which has long lifetime and low frame error rate for data transmission, and b) SINR-MP protocols route discovery process is multipath which discovers more than one SINR based route between a given source destination pair. The multiple routes selected by our SINR-MP protocol are node-disjoint in nature which increases their robustness against link failures, as failure of one route will not affect the other route. The secondary route is very useful in situations where the primary route is broken because we can now use the secondary route without causing a new route discovery process. Due to this, the network overhead caused by a route discovery process is avoided. This increases the network performance greatly. The proposed SINR-MP routing protocol is implemented in the trail version of network simulator called Qualnet.Keywords: ad hoc networks, quality of service, video streaming, H.264/SVC, multiple routes, video traces
Procedia PDF Downloads 249676 Optimization of a Cone Loudspeaker Parameter of Design Parameters by Analysis of a Narrow Acoustic Sound Pathway
Authors: Yue Hu, Xilu Zhao, Takao Yamaguchi, Manabu Sasajima, Yoshio Koike, Akira Hara
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This study tried optimization of design parameter of a cone loudspeaker unit as an example of the high flexibility of the products design. We developed an acoustic analysis software program that considers the impact of damping caused by air viscosity. In sound reproduction, it is difficult to each design the parameter of the loudspeaker. To overcome the limitation of the design problem in practice, this paper proposes a new an acoustic analysis algorithm to optimize design the parameter of the loudspeaker. The material character of cone paper and the loudspeaker edge was the design parameter, and the vibration displacement of the cone paper was the objective function. The results of the analysis were compared with the predicted value. They had high accuracy to the predicted value. These results suggest that, though the parameter design is difficult by experience and intuition, it can be performed comparatively easily using the optimization design by the developed acoustic analysis software.Keywords: air viscosity, loudspeaker, cone paper, edge, optimization
Procedia PDF Downloads 401675 Pulmonary Hydatid Cyst in a 13-Year-Old Child: A Case Report
Authors: Ghada Esheba, Bayan Hafiz, Ashwaq Al-Qarni, Abdulelah AlMalki, Esraa Kaheel
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Hydatid disease is caused by genus Echinococcus, it is transmitted to human through sheep and cattle. People who lived in an endemic area should be suspected to have the disease. Pulmonary hydatid disease can be presented by respiratory manifestations as in our case. We report a case of child, 13 years old, who was presented by shortness of breath and non-productive cough 2 months ago. The patient had an attack of hemoptysis 3 months ago but there is no history of fever, other constitutional symptoms or any medical illness. The patient has had a close contact with a horse. On examination, the patient was oriented and vitally stable. Both side of chest were moving equally with decrease air entry on the left side of the chest. Cervical lymph node enlargement was also detected. The case was provisionally diagnosed as tuberculosis. The x-ray was normal, while CT scan showed two cysts in the left side. The patient was treated surgically with resection of both cysts without lobectomy. Broncho-alveolar lavage was done and together with plural effusion and both cysts were sent for histopathology. The patient received the following medication: albendazole 200MG/BID/Orally for 30 days and Cefuroxime 250MG/Q12H/Orally for 10 days.Keywords: Echinococcus granulosus, hydatid disease, pediatrics, pulmonary hydatid cyst
Procedia PDF Downloads 273674 Analysis of Wall Deformation of the Arterial Plaque Models: Effects of Viscoelasticity
Authors: Eun Kyung Kim, Kyehan Rhee
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Viscoelastic wall properties of the arterial plaques change as the disease progresses, and estimation of wall viscoelasticity can provide a valuable assessment tool for plaque rupture prediction. Cross section of the stenotic coronary artery was modeled based on the IVUS image, and the finite element analysis was performed to get wall deformation under pulsatile pressure. The effects of viscoelastic parameters of the plaque on luminal diameter variations were explored. The result showed that decrease of viscous effect reduced the phase angle between the pressure and displacement waveforms, and phase angle was dependent on the viscoelastic properties of the wall. Because viscous effect of tissue components could be identified using the phase angle difference, wall deformation waveform analysis may be applied to predict plaque wall composition change and vascular wall disease progression.Keywords: atherosclerotic plaque, diameter variation, finite element method, viscoelasticity
Procedia PDF Downloads 216673 Design Improvement of Dental Implant-Based on Bone Remodelling
Authors: Solehuddin Shuib, Koay Boon Aik, Zainul Ahmad Rajion
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There are many types of mechanical failure on the dental implant. In this project, the failure that needs to take into consideration is the bone resorption on the dental implant. Human bone has its ability to remodel after the implantation. As the dental implant is installed into the bone, the bone will detect and change the bone structure to achieve new biomechanical environment. This phenomenon is known as bone remodeling. The objective of the project is to improve the performance of dental implant by using different types of design. These designs are used to analyze and predict the failure of the dental implant by using finite element analysis (FEA) namely ANSYS. The bone is assumed to be fully attached to the implant or cement. Hence, results are then compared with other researchers. The results were presented in the form of Von Mises stress, normal stress, shear stress analysis, and displacement. The selected design will be analyzed further based on a theoretical calculation of bone remodeling on the dental implant. The results have shown that the design constructed passed the failure analysis. Therefore, the selected design is proven to have a stable performance at the recovery stage.Keywords: dental implant, FEA, bone remodeling, design
Procedia PDF Downloads 501672 Monitoring of Belt-Drive Defects Using the Vibration Signals and Simulation Models
Authors: A. Nabhan, Mohamed R. El-Sharkawy, A. Rashed
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The main aim of this paper is to dedicate the belt drive system faults like cogs missing, misalignment and belt worm using vibration analysis technique. Experimentally, the belt drive test-rig is equipped to measure vibrations signals under different operating conditions. Finite element 3D model of belt drive system is created and vibration response analyzed using commercial finite element software ABAQUS/CAE. Root mean square (RMS) and Crest Factor will serve as indicators of average amplitude of envelope analysis signals. The vibration signals pattern obtained from the simulation model and experimental data have the same characteristics. It can be concluded that each case of the RMS is more effective in detecting the defect for acceleration response. While Crest Factor parameter has a response with the displacement and velocity of vibration signals. Also it can be noticed that the model has difficulty in completing the solution when the misalignment angle is higher than 1 degree.Keywords: simulation model, misalignment, cogs missing, vibration analysis
Procedia PDF Downloads 284671 Leakage Current Analysis of FinFET Based 7T SRAM at 32nm Technology
Authors: Chhavi Saxena
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FinFETs can be a replacement for bulk-CMOS transistors in many different designs. Its low leakage/standby power property makes FinFETs a desirable option for memory sub-systems. Memory modules are widely used in most digital and computer systems. Leakage power is very important in memory cells since most memory applications access only one or very few memory rows at a given time. As technology scales down, the importance of leakage current and power analysis for memory design is increasing. In this paper, we discover an option for low power interconnect synthesis at the 32nm node and beyond, using Fin-type Field-Effect Transistors (FinFETs) which are a promising substitute for bulk CMOS at the considered gate lengths. We consider a mechanism for improving FinFETs efficiency, called variable supply voltage schemes. In this paper, we’ve illustrated the design and implementation of FinFET based 4x4 SRAM cell array by means of one bit 7T SRAM. FinFET based 7T SRAM has been designed and analysis have been carried out for leakage current, dynamic power and delay. For the validation of our design approach, the output of FinFET SRAM array have been compared with standard CMOS SRAM and significant improvements are obtained in proposed model.Keywords: FinFET, 7T SRAM cell, leakage current, delay
Procedia PDF Downloads 455670 A Mathematical Description of a Growing Cell Colony Based on the Mechanical Bidomain Model
Authors: Debabrata Auddya, Bradley J. Roth
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The mechanical bidomain model is used to describe a colony of cells growing on a substrate. Analytical expressions are derived for the intracellular and extracellular displacements. Mechanotransduction events are driven by the difference between the displacements in the two spaces, corresponding to the force acting on integrins. The equation for the displacement consists of two terms: one proportional to the radius that is the same in the intracellular and extracellular spaces (the monodomain term) and one that is proportional to a modified Bessel function that is responsible for mechanotransduction (the bidomain term). The model predicts that mechanotransduction occurs within a few length constants of the colony’s edge, and an expression for the length constant contains the intracellular and extracellular shear moduli and the spring constant of the integrins coupling the two spaces. The model predictions are qualitatively consistent with experiments on human embryonic stem cell colonies, in which differentiation is localized near the edge.Keywords: cell colony, integrin, mechanical bidomain model, stem cell, stress-strain, traction force
Procedia PDF Downloads 238669 Effect of Elastic Modulus Anisotropy on Helical Piles Behavior in Sandy Soil
Authors: Reza Ziaie Moayed, Javad Shamsi Soosahab
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Helical piles are being used extensively in engineering applications all over the world. There are insufficient studies on the helical piles' behavior in anisotropic soils. In this paper, numerical modeling was adopted to investigate the effect of elastic modulus anisotropy on helical pile behavior resting on anisotropic sand by using a finite element limit analysis. The load-displacement behavior of helical piles under compression and tension loads is investigated in different relative densities of soils, and the effect of the ratio of horizontal elastic modulus with respect to vertical elastic modulus (EH/EV) is evaluated. The obtained results illustrate that in sandy soils, the anisotropic ratio of elastic modulus (EH/EV) has notable effect on bearing capacity of helical piles in different relative density. Therefore, it may be recommended that the effect of anisotropic condition of soil elastic modulus should be considered in helical piles behavior.Keywords: helical piles, bearing capacity, numerical modeling, soil anisotropy
Procedia PDF Downloads 163668 An Automatic Generating Unified Modelling Language Use Case Diagram and Test Cases Based on Classification Tree Method
Authors: Wassana Naiyapo, Atichat Sangtong
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The processes in software development by Object Oriented methodology have many stages those take time and high cost. The inconceivable error in system analysis process will affect to the design and the implementation process. The unexpected output causes the reason why we need to revise the previous process. The more rollback of each process takes more expense and delayed time. Therefore, the good test process from the early phase, the implemented software is efficient, reliable and also meet the user’s requirement. Unified Modelling Language (UML) is the tool which uses symbols to describe the work process in Object Oriented Analysis (OOA). This paper presents the approach for automatically generated UML use case diagram and test cases. UML use case diagram is generated from the event table and test cases are generated from use case specifications and Graphic User Interfaces (GUI). Test cases are derived from the Classification Tree Method (CTM) that classify data to a node present in the hierarchy structure. Moreover, this paper refers to the program that generates use case diagram and test cases. As the result, it can reduce work time and increase efficiency work.Keywords: classification tree method, test case, UML use case diagram, use case specification
Procedia PDF Downloads 162667 Advanced Hybrid Particle Swarm Optimization for Congestion and Power Loss Reduction in Distribution Networks with High Distributed Generation Penetration through Network Reconfiguration
Authors: C. Iraklis, G. Evmiridis, A. Iraklis
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Renewable energy sources and distributed power generation units already have an important role in electrical power generation. A mixture of different technologies penetrating the electrical grid, adds complexity in the management of distribution networks. High penetration of distributed power generation units creates node over-voltages, huge power losses, unreliable power management, reverse power flow and congestion. This paper presents an optimization algorithm capable of reducing congestion and power losses, both described as a function of weighted sum. Two factors that describe congestion are being proposed. An upgraded selective particle swarm optimization algorithm (SPSO) is used as a solution tool focusing on the technique of network reconfiguration. The upgraded SPSO algorithm is achieved with the addition of a heuristic algorithm specializing in reduction of power losses, with several scenarios being tested. Results show significant improvement in minimization of losses and congestion while achieving very small calculation times.Keywords: congestion, distribution networks, loss reduction, particle swarm optimization, smart grid
Procedia PDF Downloads 445666 Hegemonic Salaryman Masculinity: Case Study of Transitional Male Gender Roles in Today's Japan
Authors: D. Norton
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This qualitative study focuses on the lived experience and displacement of young white-collar masculinities in Japan. In recent years, the salaryman lifestyle has undergone significant disruption - increased competition for regular employment, rise in non-regular structurings of labour across public/private sectors, and shifting role expectations within the home. Despite this, related scholarship hints at a continued reinforcement of the traditional male gender role - that the salaryman remains a key benchmark of Japanese masculine identity. For those in structural proximity to these more ‘normative’ performativities, interest lies their engagement with such narratives - how they make sense of their masculinity in response to stated changes. In light of the historical emphasis on labour and breadwinning logics, notions of respective security or precarity generated as a result remain unclear. Similarly, concern extends to developments within the private sphere - by what means young white-collar men construct ideas of singlehood and companionship according to traditional gender ideologies or more contemporary, flexible readings. The influence of these still-emergent status distinctions on the logics of the social group in question is yet to be explored in depth by gender scholars. This project, therefore, focuses on a salaryman archetype as hegemonic - its transformation amidst these changes and socialising mechanisms that continue to legitimate unequal gender hierarchies. For data collection, a series of ethnographic interviews were held over a period of 12 months with university-educated, white-collar male employees from both Osaka and the Greater Tokyo Area. Findings suggest a modern salaryman ideal reflecting both continuities and shifts within white-collar employment. Whilst receptive to more contemporary workplace practices, the narratives of those interviewed remain imbued with logics supporting patterns of internal hegemony. Regular/non-regular distinction emerged as the foremost variable for both material and discursive patterns of white-collar stratification, with variants of displacement for each social group. Despite the heightened valorisation of stable employment, regular workers articulated various concerns over a model of corporate masculinity seen to be incompatible with recent socioeconomic developments. Likewise, non-regular employees face detachment owing to a still-inflexible perception of their working masculinity as marginalized amidst economic precarity. In seeking to negotiate respective challenges, those interviewed demonstrated an engagement with various concurrent social changes that would often either accommodate, reinforce, or expand upon traditional role behaviours. Few of these narratives offered any notable transgression of said ideal, however, suggesting that within the spectre of white-collar employment in Japan for the near future, any substantive transformation of corporate masculinity remains dependant upon economic developments, less so the agency of those involved.Keywords: gender ideologies, hegemonic masculinity, Japan, white-collar employment
Procedia PDF Downloads 125665 The Effect of Masonry Infills on the Seismic Response of Reinforced Concrete Structures
Authors: Mohammad Reza Ameri, Ali Massumi, Behnam Mahboubi
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The performance of masonry infilled frames during the past earthquakes shows that the infill panels play a major role as earthquake-resistant elements. The present study examines the influence of infill panels on seismic behavior of RC frame structures. For this purpose, several low- and mid-rise RC frames (two-, four-, seven-, and ten story) were numerically investigated. Reinforced masonry infill panels were then placed within the frames and the models were subjected to several nonlinear incremental static and dynamic analyses. The results of analyses showed that the use of reinforced masonry infill panels in RC frame structures can have beneficial effects on structural performance. It was confirmed that the use of masonry infill panels results in an increment in strength and stiffness of the framed buildings, followed by a reduction in displacement demand for the structural systems.Keywords: reinforced masonry infill panels, nonlinear static analysis, incremental dynamic analysis, low-rise reinforced concrete frames, mid-rise reinforced concrete frames
Procedia PDF Downloads 320664 Study of the Behavior of Geogrid Mechanically Stabilized Earth Walls Under Cyclic Loading
Authors: Yongzhe Zhao, Ying Liu, Zhiyong Liu, Hui You
Abstract:
The soil behind retaining wall is normally subjected to cyclic loading, for example traffic loading. Geotextile has been widely used to reinforce the soil for the purpose of reducing the settlement of the soil. A series of physical model tests were performed to investigate the settlement of footing under cyclic loading. The settlement of the footing, ground deformation and the vertical earth pressure in subsoil were presented and discussed under different types of geotextiles. The results indicate that including geotextiles significantly decreases the footing settlement and the stiffer the geotextile, the less the settlement. Under cyclic loading, the soil below the footing shows dilation within certain depths and beyond that it experiences contraction. The location of footing relative to the retaining wall has important effects on the deformation behavior of the soil in the ground, and the closer the footing to the retaining wall, the greater the contraction soil shows. This is because the retaining wall experienced greater lateral displacement.Keywords: physical model tests, reinforced retaining wall, cyclic loading, footing
Procedia PDF Downloads 155663 Decode and Forward Cooperative Protocol Enhancement Using Interference Cancellation
Authors: Siddeeq Y. Ameen, Mohammed K. Yousif
Abstract:
Cooperative communication systems are considered to be a promising technology to improve the system capacity, reliability and performances over fading wireless channels. Cooperative relaying system with a single antenna will be able to reach the advantages of multiple antenna communication systems. It is ideally suitable for the distributed communication systems; the relays can cooperate and form virtual MIMO systems. Thus the paper will aim to investigate the possible enhancement of cooperated system using decode and forward protocol. On decode and forward an attempt to cancel or at least reduce the interference instead of increasing the SNR values is achieved. The latter can be achieved via the use group of relays depending on the channel status from source to relay and relay to destination respectively. In the proposed system, the transmission time has been divided into two phases to be used by decode and forward protocol. The first phase has been allocated for the source to transmit its data whereas the relays and destination nodes are in receiving mode. On the other hand, the second phase is allocated for the first and second groups of relay nodes to relay the data to the destination node. Simulations results have shown an improvement in performance is achieved compared to the conventional decode and forward in terms of BER and transmission rate.Keywords: cooperative systems, decode and forward, interference cancellation, virtual MIMO
Procedia PDF Downloads 323662 Case Report: Clinical Improvement of Forbrain Neurologic Signs in 3- Month- Old Persian Mastiff Dog with Calvarial Hyperostosis Syndrome after Corticosteroid, Antiepileptic and Antibiotic Therapy
Authors: Hamidreza Jahani, Zahra Salehzadeh, Ehsan Amini, Mohsen Tohidifar
Abstract:
Calvarial Hyperostosis Syndrome (CHS) is a benign bone disease of the skull. It is a non-neoplastic and proliferative bone disease, and the main feature of the disease is progressive and asymmetrical bone involvement. CHS is mostly reported in young male and female bullmastiff dogs and less frequently in other breeds. The etiology of CHS is unknown. This is the first case report of CHS in Iran. A 3-month-old male Persian Mastiff was presented with chief complaints of multiple episodes of seizure, pacing, bizarre behavior, delayed growth, head pressing, and difficulty in opening the mouth. Central blindness and open fontanelles were observed in clinical examination. No abnormality was found in the complete blood count and routine blood biochemical tests. CT scan findings include cortical thickening of frontal and parietal bones and enlargement of the left retropharyngeal lymph node. For treatment, oral clindamycin for two weeks, prednisolone and phenobarbital for one month, respectively, were administrated, and the case showed improvement after a week and recovered after one month.Keywords: calvarial hyperostosis, Persian Mastiff, frontal bone, seizure
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