Search results for: mechanical parameters
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4697

Search results for: mechanical parameters

4577 Self Organizing Mixture Network in Mixture Discriminant Analysis: An Experimental Study

Authors: Nazif Çalış, Murat Erişoğlu, Hamza Erol, Tayfun Servi

Abstract:

In the recent works related with mixture discriminant analysis (MDA), expectation and maximization (EM) algorithm is used to estimate parameters of Gaussian mixtures. But, initial values of EM algorithm affect the final parameters- estimates. Also, when EM algorithm is applied two times, for the same data set, it can be give different results for the estimate of parameters and this affect the classification accuracy of MDA. Forthcoming this problem, we use Self Organizing Mixture Network (SOMN) algorithm to estimate parameters of Gaussians mixtures in MDA that SOMN is more robust when random the initial values of the parameters are used [5]. We show effectiveness of this method on popular simulated waveform datasets and real glass data set.

Keywords: Self Organizing Mixture Network, MixtureDiscriminant Analysis, Waveform Datasets, Glass Identification, Mixture of Multivariate Normal Distributions

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4576 Dynamic Behavior of Brain Tissue under Transient Loading

Authors: Y. J. Zhou, G. Lu

Abstract:

In this paper, an analytical study is made for the dynamic behavior of human brain tissue under transient loading. In this analytical model the Mooney-Rivlin constitutive law is coupled with visco-elastic constitutive equations to take into account both the nonlinear and time-dependent mechanical behavior of brain tissue. Five ordinary differential equations representing the relationships of five main parameters (radial stress, circumferential stress, radial strain, circumferential strain, and particle velocity) are obtained by using the characteristic method to transform five partial differential equations (two continuity equations, one motion equation, and two constitutive equations). Analytical expressions of the attenuation properties for spherical wave in brain tissue are analytically derived. Numerical results are obtained based on the five ordinary differential equations. The mechanical responses (particle velocity and stress) of brain are compared at different radii including 5, 6, 10, 15 and 25 mm under four different input conditions. The results illustrate that loading curves types of the particle velocity significantly influences the stress in brain tissue. The understanding of the influence by the input loading cures can be used to reduce the potentially injury to brain under head impact by designing protective structures to control the loading curves types.

Keywords: Analytical method, mechanical responses, spherical wave propagation, traumatic brain injury.

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4575 Synthesis of Polystyrene Grafting Filler Nanoparticles: Effect of Grafting on Mechanical Reinforcement

Authors: M. Khlifa, A. Youssef, A. F. Zaed, A. Kraft, V. Arrighi

Abstract:

A series of polystyrene (PS) nanoparticles were prepared by grafting polystyrene from both aggregated silica and colloidally dispersed silica nanoparticles using atom-transfer radical polymerisation (ATRP). Cross-linking and macroscopic gelation were minimised by using a miniemulsion system. The thermal and mechanical behaviour of the nanocomposites have been examined by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA).

Keywords: ATRP, nanocomposites, polystyrene, reinforcement.

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4574 Variation of Metrological Parameters as They Affect the Tropospheric Radio Refractivity for Akure South-West Nigeria

Authors: Famoriji J.Oluwole

Abstract:

This research work examines the effect of variations of metrological parameters on the tropospheric radio refractivity during dry and raining seasons for Akure in 2013. The daily averages of radio refractivity during dry (January) and raining (August) seasons were calculated from the data obtained from the Nigeria Metrological Agency (NIMET). The data that was used for the computation of radio refractivity is a daily interval of the variations of metrological parameters for each day in the troposphere for Akure. Consequently, the daily averages of radio refractivity during raining season (August) were greater than the results in dry season (January) as a result of the variations in meteorological parameters such as temperature, humidity and atmospheric pressure in the lower troposphere.

Keywords: Troposphere, Radio refractivity, Akure, Meteorological parameters.

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4573 Inferences on Compound Rayleigh Parameters with Progressively Type-II Censored Samples

Authors: Abdullah Y. Al-Hossain

Abstract:

This paper considers inference under progressive type II censoring with a compound Rayleigh failure time distribution. The maximum likelihood (ML), and Bayes methods are used for estimating the unknown parameters as well as some lifetime parameters, namely reliability and hazard functions. We obtained Bayes estimators using the conjugate priors for two shape and scale parameters. When the two parameters are unknown, the closed-form expressions of the Bayes estimators cannot be obtained. We use Lindley.s approximation to compute the Bayes estimates. Another Bayes estimator has been obtained based on continuous-discrete joint prior for the unknown parameters. An example with the real data is discussed to illustrate the proposed method. Finally, we made comparisons between these estimators and the maximum likelihood estimators using a Monte Carlo simulation study.

Keywords: Progressive type II censoring, compound Rayleigh failure time distribution, maximum likelihood estimation, Bayes estimation, Lindley's approximation method, Monte Carlo simulation.

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4572 Comparative Studies on Dissimilar Metals thin Sheets Using Laser Beam Welding - A Review

Authors: K. Kalaiselvan, A. Elango, N. M. Nagarajan

Abstract:

Laser beam welding for the dissimilar Titanium and Aluminium thin sheets is an emerging area which is having wider applications in aerospace, aircraft, automotive, electronics and in other industries due to its high speed, non-contact, precision with low heat effects, least welding distortion, low labor costs and convenient operation. Laser beam welding of dissimilar metal combinations are increasingly demanded due to high energy densities with small fusion and heat affected zones. Furthermore, no filler or electrode material is required and contamination of weld is also very small. The present study is to reviews the influence of different parameters like laser power, welding speed, power density, beam diameter, focusing distance and type of shielding gas on the mechanical properties of dissimilar metal combinations like SS/Al, Cu/Al and Ti/Al focusing on aluminum to other materials. Research findings reveal that Ti/Al combination gives better metallurgical and mechanical properties than other combinations such as SS/Al and Cu/Al.

Keywords: Laser Beam Welding, dissimilar metals, SS/Al, Cu/Al and Ti/Al sheets.

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4571 Microstructural Evolution of an Interface Region in a Nickel-Based Superalloy Joint Produced by Direct Energy Deposition

Authors: M. Ferguson, T. Konkova, I. Violatos

Abstract:

Microstructure analysis of additively manufactured (AM) materials is an important step in understanding the interrelationship between mechanical properties and materials performance. Literature on the effect of a laser-based AM process parameters on the microstructure in the substrate-deposit interface is limited. The interface region, the adjoining area of substrate and deposit, is characterized by the presence of the fusion zone (FZ) and heat affected zone (HAZ) experiencing rapid thermal gyrations resulting in thermal induced transformations. Inconel 718 was utilized as a work material for both the substrate and deposit. Three blocks of Inconel 718 material were deposited by Direct Energy Deposition (DED) using three different laser powers, 550W, 750W and 950W, respectively. A coupled thermo-mechanical transient approach was utilized to correlate temperature history to the evolution of microstructure. Thermal history of the deposition process was monitored with the thermocouples installed inside the substrate material. Interface region of the blocks were analysed with Optical Microscopy (OM) and Scanning Electron Microscopy (SEM) including electron back-scattered diffraction (EBSD) technique. Laser power was found to influence the dissolution of intermetallic precipitated phases in the substrate and grain growth in the interface region. Microstructure and thermal history data were utilized to draw conclusive comparisons between the investigated process parameters.

Keywords: Additive manufacturing, direct energy deposition, electron back-scatter diffraction, finite element analysis, Inconel 718, microstructure, optical microscopy, scanning electron microscopy, substrate-deposit interface region.

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4570 Effects of an Added Foaming Agent on Hydro-Mechanical Properties of Soil

Authors: Moez Selmi, Mariem Kacem, Mehrez Jamei, Philippe Dubujet

Abstract:

Earth pressure balance (EPB) tunnel boring machines are designed for digging in different types of soil, especially clay soils. This operation requires the treatment of soil by lubricants to facilitate the procedure of excavation. A possible use of this soil is limited by the effect of treatment on the hydro-mechanical properties of the soil. This work aims to study the effect of a foaming agent on the hydro-mechanical properties of clay soil. The injection of the foam agent in the soil leads to create a soil matrix in which they are incorporated gas bubbles. The state of the foam in the soil is scalable thanks to the degradation of the gas bubbles in the soil.

Keywords: EPB, clay soils, foam agent, hydro-mechanical properties, degradation.

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4569 A Comparison of Single Point Incremental Forming Formability between Carbon Steel and Stainless Steel

Authors: K. Rattanachan

Abstract:

In sheet metal forming process, raw material mechanical properties are important parameters. This paper is to compare the wall’s incline angle or formability of SS 400 steel and SUS 304 stainless steel in single point incremental forming. The two materials are ferrous base alloyed, which have the different unit cell, mechanical property and chemical composition. They were forming into cone shape specimens having 100 mm diameter with different wall’s incline angle: 90o, 75o and 60o. The investigation was continued until the specimens formed surface facture. The experimental result showed that the smaller the wall incline angle higher the formability with the both materials. The formability limit of the ferrous base alloy was approx. 60o wall’s incline angle. By nature, SS 400 has higher formability than SUS 304. This result can be used as the initial data in designing the single point incremental forming parts.

Keywords: NC incremental forming, Single point incremental forming, Wall incline angle, Formability.

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4568 Assessment of Compaction Temperatures on Hot Mix Asphalt (HMA) Properties

Authors: Houman Saedi

Abstract:

Hot Mix Asphalt (HMA) is one of the most commonest constructed asphalts in Iran and the quality control of constructed roads with HMA have been always paid due attention by researchers. The quality control of constructed roads with this method is being usually carried out by measuring volumetric parameters of HMA marshall samples. One of the important parameters that has a critical role in changing these volumetric parameters is “compaction temperature"; which as a result of its changing, volumetric parameters of Marshall Samples and subsequently constructed asphalt is encountered with variations. In this study, considering the necessity of preservation of the compaction temperature, the effect of various temperatures on Hot Mix Asphalt (HMA) samples properties has been evaluated. As well, to evaluate the effect of this parameter on different grading, two different grading (Top coat index grading and binder index grading) have been used and samples were compacted at 5 various temperatures.

Keywords: Compaction Temperature, HMA, Volumetric Parameters, Marshall Method

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4567 Improvement Approach on Rotor Time Constant Adaptation with Optimum Flux in IFOC for Induction Machines Drives

Authors: S. Grouni, R. Ibtiouen, M. Kidouche, O. Touhami

Abstract:

Induction machine models used for steady-state and transient analysis require machine parameters that are usually considered design parameters or data. The knowledge of induction machine parameters is very important for Indirect Field Oriented Control (IFOC). A mismatched set of parameters will degrade the response of speed and torque control. This paper presents an improvement approach on rotor time constant adaptation in IFOC for Induction Machines (IM). Our approach tends to improve the estimation accuracy of the fundamental model for flux estimation. Based on the reduced order of the IM model, the rotor fluxes and rotor time constant are estimated using only the stator currents and voltages. This reduced order model offers many advantages for real time identification parameters of the IM.

Keywords: Indirect Field Oriented Control (IFOC), InductionMachine (IM), Rotor Time Constant, Parameters ApproachAdaptation. Optimum rotor flux.

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4566 Complex Method for Localized Muscle Fatigue Evaluation

Authors: Vasilescu M., Rusu L., Nestianu V., Romanescu F., Dragomir M

Abstract:

The research was designed to examine the relationship between the development of muscle fatigue and the effect it has on sport performance, specifically during maximal voluntary contraction. This kind of this investigation using simultaneous electrophysiological and mechanical recordings, based on advanced mathematical processing, allows us to get parameters, and indexes in a short time, and finally, the mapping to use for the thorough investigation of the muscle contraction force, respectively the phenomenon of local muscle fatigue, both for athletes and other subjects.

Keywords: Electromyography, mechanomyography, musclefatigue

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4565 Maximum Likelihood Estimation of Burr Type V Distribution under Left Censored Samples

Authors: N. Feroze, M. Aslam

Abstract:

The paper deals with the maximum likelihood estimation of the parameters of the Burr type V distribution based on left censored samples. The maximum likelihood estimators (MLE) of the parameters have been derived and the Fisher information matrix for the parameters of the said distribution has been obtained explicitly. The confidence intervals for the parameters have also been discussed. A simulation study has been conducted to investigate the performance of the point and interval estimates.

Keywords: Fisher information matrix, confidence intervals, censoring.

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4564 Modal Dynamic Analysis of a Mechanism with Deformable Elements from an Oil Pump Unit Structure

Authors: N. Dumitru, S. Dumitru, C. Copilusi, N. Ploscaru

Abstract:

On this research, experimental analyses have been performed in order to determine the oil pump mechanism dynamics and stability from an oil unit mechanical structure. The experimental tests were focused on the vibrations which occur inside of the rod element during functionality of the oil pump unit. The oil pump mechanism dynamic parameters were measured and also determined through numerical computations. Entire research is based on the oil pump unit mechanical system virtual prototyping. For a complete analysis of the mechanism, the frequency dynamic response was identified, mainly for the mechanism driven element, based on two methods: processing and virtual simulations with MSC Adams aid and experimental analysis. In fact, through this research, a complete methodology is presented where numerical simulations of a mechanism with deformed elements are developed on a dynamic mode and these can be correlated with experimental tests.

Keywords: Modal dynamic analysis, oil pump, vibrations, flexible elements, frequency response.

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4563 Optimizing Turning Parameters for Cylindrical Parts Using Simulated Annealing Method

Authors: Farhad Kolahan, Mahdi Abachizadeh

Abstract:

In this paper, a simulated annealing algorithm has been developed to optimize machining parameters in turning operation on cylindrical workpieces. The turning operation usually includes several passes of rough machining and a final pass of finishing. Seven different constraints are considered in a non-linear model where the goal is to achieve minimum total cost. The weighted total cost consists of machining cost, tool cost and tool replacement cost. The computational results clearly show that the proposed optimization procedure has considerably improved total operation cost by optimally determining machining parameters.

Keywords: Optimization, Simulated Annealing, Machining Parameters, Turning Operation.

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4562 An Evaluation of TIG Welding Parametric Influence on Tensile Strength of 5083 Aluminium Alloy

Authors: Lakshman Singh, Rajeshwar Singh, Naveen Kumar Singh, Davinder Singh, Pargat Singh

Abstract:

Tungsten Inert Gas (TIG) welding is a high quality welding process used to weld the thin metals and their alloy. 5083 Aluminium alloys play an important role in engineering and metallurgy field because of excellent corrosion properties, ease of fabrication and high specific strength coupled with best combination of toughness and formability.

TIG welding technique is one of the precise and fastest processes used in aerospace, ship and marine industries. TIG welding process is used to analyze the data and evaluate the influence of input parameters on tensile strength of 5083 Al-alloy specimens with dimensions of 100mm long x 15mm wide x 5mm thick. Welding current (I), gas flow rate (G) and welding speed (S) are the input parameters which effect tensile strength of 5083 Al-alloy welded joints. As welding speed increased, tensile strength increases first till optimum value and after that both decreases by increasing welding speed further. Results of the study show that maximum tensile strength of 129 MPa of weld joint are obtained at welding current of 240 Amps, gas flow rate of 7 Lt/min and welding speed of 98 mm/min. These values are the optimum values of input parameters which help to produce efficient weld joint that have good mechanical properties as a tensile strength.

Keywords: 5083 Aluminium alloy, Gas flow rate, TIG welding, Welding current, Welding speed and Tensile strength.

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4561 Characterization of Aluminium Alloy 6063 Hybrid Metal Matrix Composite by Using Stir Casting Method

Authors: Balwinder Singh

Abstract:

The present research is a paper on the characterization of aluminum alloy-6063 hybrid metal matrix composites using three different reinforcement materials (SiC, red mud, and fly ash) through stir casting method. The red mud was used in solid form, and particle size range varies between 103-150 µm. During this investigation, fly ash is received from Guru Nanak Dev Thermal Plant (GNDTP), Bathinda. The study has been done by using Taguchi’s L9 orthogonal array by taking fraction wt.% (SiC 5%, 7.5%, and 10% and Red Mud and Fly Ash 2%, 4%, and 6%) as input parameters with their respective levels. The study of the mechanical properties (tensile strength, impact strength, and microhardness) has been done by using Analysis of Variance (ANOVA) with the help of MINITAB 17 software. It is revealed that silicon carbide is the most significant parameter followed by red mud and fly ash affecting the mechanical properties, respectively. The fractured surface morphology of the composites using Field Emission Scanning Electron Microscope (FESEM) shows that there is a good mixing of reinforcement particles in the matrix. Energy-dispersive X-ray spectroscopy (EDS) was performed to know the presence of the phases of the reinforced material.

Keywords: Reinforcement, silicon carbide, fly ash, red mud.

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4560 Temperature Effect on the Mechanical Properties of Pd3Rh and PdRh3 Ordered Alloys

Authors: J. Davoodi , J. Moradi

Abstract:

The aim of this research was to calculate the mechanical properties of Pd3Rh and PdRh3 ordered alloys. The molecular dynamics (MD) simulation technique was used to obtain temperature dependence of the energy, the Yong modulus, the shear modulus, the bulk modulus, Poisson-s ratio and the elastic stiffness constants at the isobaric-isothermal (NPT) ensemble in the range of 100-325 K. The interatomic potential energy and force on atoms were calculated by Quantum Sutton-Chen (Q-SC) many body potential. Our MD simulation results show the effect of temperature on the cohesive energy and mechanical properties of Pd3Rh as well as PdRh3 alloys. Our computed results show good agreement with the experimental results where they have been available.

Keywords: Pd-Rh alloy; Mechanical properties; Moleculardynamics simulation

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4559 Impact of Altered Behavioral Condition on Markers of Oxidative Stress and Different Biochemical Parameters

Authors: D. S. Mohale, A. V. Chandewar

Abstract:

Aim- Study was undertaken to investigate the effect of altered behavioral condition like depression on various oxidative stress markers and biochemical parameters in rats. Methods- Rats were subjected for short (21 days) and long term (84 days) social isolation; the rats displayed an increase in depression on force swim test relative to control. Various markers of oxidative stress like lipid per oxidation (LPO), reduced glutathione (GSH), Supers oxide dismutase (SOD), catalase (CAT) and biochemical parameters like SGOT, SGPT, and blood glucose were determined. Results- There was significant increase in the level of LPO and decrease in the levels of GSH, SOD and CAT after long term isolation. Biochemical parameters were significantly altered after social isolation. Conclusion- Increased oxidative stress in depression which may leads to alteration of biochemical parameters.

Keywords: Depression, Glucose, LPO, Oxidative stress.

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4558 Morphological and Dynamic Mechanical Analyses of a Local Clay/Plantain Fiber Filled Hybrid Polystyrene Composites

Authors: K. P. Odimayomi, A. G. Adeniyi, S. A. Abdulkareem, F. M. Oladipo Emmanuel, C. A. Adeyanju, M. A Amoloye

Abstract:

The abundant availability of the local clay/plantain fiber coupled with the various renewable and sustainability advantages has led to their choice as co-fillers in the development of a hybrid polystyrene composite. The prime objective of this study is to evaluate the morphological and dynamic mechanical properties using Scanning Electron Microscopy and Dynamic Mechanical Analysis. The hybrid polystyrene composite development was developed via the hand-lay-up method. All processing including the constituent mixing and curing were achieved at room temperature (25 ± 2 ℃).   The mechanical characteristics of the developed composites via Dynamic Mechanical Analysis (DMA) confirm an indirect relationship between time and storage modulus, this pattern becomes more evident at higher frequencies. It is clearly portrayed that the addition of clay and plantain fiber in the polystyrene matrix increases the stiffness of the developed composite.

Keywords: Morphology, DMA, Akerebiata clay, plantain fiber, hybrid polystyrene composites.

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4557 Experimental Study on Thermomechanical Properties of New-Generation ODS Alloys

Authors: O. Khalaj, B. Mašek, H. Jirková, J. Svoboda

Abstract:

By using a combination of new technologies together with an unconventional use of different types of materials, specific mechanical properties and structures of the material can be achieved. Some possibilities are enabled by a combination of powder metallurgy in the preparation of a metal matrix with dispersed stable particles achieved by mechanical alloying and hot consolidation. This paper explains the thermomechanical properties of new generation of Oxide Dispersion Strengthened alloys (ODS) within three ranges of temperature with specified deformation profiles. The results show that the mechanical properties of new ODS alloys are significantly affected by the thermomechanical treatment.

Keywords: Hot forming, ODS, alloys, thermomechanical, Fe-Al, Al2O3.

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4556 Influence of Taguchi Selected Parameters on Properties of CuO-ZrO2 Nanoparticles Produced via Sol-gel Method

Authors: H. Abdizadeh, Y. Vahidshad

Abstract:

The present paper discusses the selection of process parameters for obtaining optimal nanocrystallites size in the CuOZrO2 catalyst. There are some parameters changing the inorganic structure which have an influence on the role of hydrolysis and condensation reaction. A statistical design test method is implemented in order to optimize the experimental conditions of CuO-ZrO2 nanoparticles preparation. This method is applied for the experiments and L16 orthogonal array standard. The crystallites size is considered as an index. This index will be used for the analysis in the condition where the parameters vary. The effect of pH, H2O/ precursor molar ratio (R), time and temperature of calcination, chelating agent and alcohol volume are particularity investigated among all other parameters. In accordance with the results of Taguchi, it is found that temperature has the greatest impact on the particle size. The pH and H2O/ precursor molar ratio have low influences as compared with temperature. The alcohol volume as well as the time has almost no effect as compared with all other parameters. Temperature also has an influence on the morphology and amorphous structure of zirconia. The optimal conditions are determined by using Taguchi method. The nanocatalyst is studied by DTA-TG, XRD, EDS, SEM and TEM. The results of this research indicate that it is possible to vary the structure, morphology and properties of the sol-gel by controlling the above-mentioned parameters.

Keywords: CuO-ZrO2 Nanoparticles, Sol-gel, Taguchi method.

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4555 Mechanical and Thermal Properties Characterisation of Vinyl Ester Matrix Nanocomposites Based On Layered Silicate

Authors: A. I. Alateyah, H. N. Dhakal, Z. Y. Zhang

Abstract:

The mechanical properties including flexural and tensile of neat vinyl ester and polymer based on layered silicate nanocomposite materials are discussed. The addition of layered silicate into the polymer matrix increased the tensile and flexural modulus up to 1 wt.% clay loading. The incorporation of more clay resulted in decreasing the mechanical properties which was traced to the existence of aggregation layers. Likewise, up to 1 wt.% clay loading, the thermal behaviour showed significant improvements and at higher clay loading the thermal pattern was reduced. The aggregation layers imparted a negative impact on the overall mechanical and thermal properties. Wide Angle X-ray Diffraction, Scanning Electron Microscopy and Transmission Electron Microscopy were utilised in order to characterise the interlamellar structure of nanocomposites.

Keywords: Vinyl ester, nanocomposites, layered silicate, mechanical properties, thermal analysis.

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4554 Production and Mechanical Characterization of Ballistic Thermoplastic Composite Materials

Authors: D. Korsacilar, C. Atas

Abstract:

In this study, first thermoplastic composite materials /plates that have high ballistic impact resistance were produced. For this purpose, the thermoplastic prepreg and the vacuum bagging technique were used to produce a composite material. Thermoplastic prepregs (resin-impregnated fiber) that are supplied ready to be used, namely high-density polyethylene (HDPE) was chosen as matrix and unidirectional glass fiber was used as reinforcement. In order to compare the fiber configuration effect on mechanical properties, unidirectional and biaxial prepregs were used. Then the microstructural properties of the composites were investigated with scanning electron microscopy (SEM) analysis. Impact properties of the composites were examined by Charpy impact test and tensile mechanical tests and then the effects of ultraviolet irradiation were investigated on mechanical performance.

Keywords: Ballistic, Composite, Thermoplastic.

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4553 Synthesis and Study the Effect of HNTs on PVA/Chitosan Composite Material

Authors: Malek Ali

Abstract:

Composites materials of Poly (vinyl alcohol) (PVA)/Chitosan (CS) have been synthesized and characterized successfully. HNTs have been added to composites to enhance the mechanical and degradation properties by hydrogen bonding interactions, compatibility, and chemical crosslink between HNTs and PVA. PVA/CS/HNTs composites prepared with different concentration ratio. SEM micrographs of composites surface showed that more agglomeration with more chitosan ratio. Mechanical and degradation properties were characterized and the result indicates that Mechanical and degradation of 80%PVA/5%Chitosan/15%HNTs higher than the others PVA/CS/HNTs composites.

Keywords: PVA/Chitosan, Composites, PVA/CS/HNTs, HNTs.

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4552 Region-Based Image Fusion with Artificial Neural Network

Authors: Shuo-Li Hsu, Peng-Wei Gau, I-Lin Wu, Jyh-Horng Jeng

Abstract:

For most image fusion algorithms separate relationship by pixels in the image and treat them more or less independently. In addition, they have to be adjusted different parameters in different time or weather. In this paper, we propose a region–based image fusion which combines aspects of feature and pixel-level fusion method to replace only by pixel. The basic idea is to segment far infrared image only and to add information of each region from segmented image to visual image respectively. Then we determine different fused parameters according different region. At last, we adopt artificial neural network to deal with the problems of different time or weather, because the relationship between fused parameters and image features are nonlinear. It render the fused parameters can be produce automatically according different states. The experimental results present the method we proposed indeed have good adaptive capacity with automatic determined fused parameters. And the architecture can be used for lots of applications.

Keywords: Image fusion, Region-based fusion, Segmentation, Neural network, Multi-sensor.

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4551 Mechanical Properties of Ultra High Performance Concrete

Authors: Prabhat Ranjan Prem, B.H.Bharatkumar, Nagesh R Iyer

Abstract:

A research program is conducted to evaluate the mechanical properties of Ultra High Performance Concrete, target compressive strength at the age of 28 days being more than 150 MPa. The methodology to develop such mix has been explained. The material properties, mix design and curing regime are determined. The material attributes are understood by studying the stress strain behaviour of UHPC cylinders under uniaxial compressive loading. The load –crack mouth opening displacement (cmod) of UHPC beams, flexural strength and fracture energy was evaluated using third point loading test. Compressive strength and Split tensile strength results are determined to find out the compressive and tensile behaviour. Residual strength parameters are presented vividly explaining the flexural performance, toughness of concrete.Durability studies were also done to compare the effect of fibre to that of a control mix For all the studies the Mechanical properties were evaluated by varying the percentage and aspect ratio of steel fibres The results reflected that higher aspect ratio and fibre volume produced drastic changes in the cube strength, cylinder strength, post peak response, load-cmod, fracture energy flexural strength, split tensile strength, residual strength and durability. In regards to null application of UHPC in India, an initiative is undertaken to comprehend the mechanical behaviour of UHPC, which will be vital for longer run in commercialization for structural applications.

Keywords: Ultra High Performance Concrete, Reinforcement Index, Compressive Strength, Tensile Strength, Flexural Strength, Residual Strength, Fracture Energy, Stress-Strain Relationships, Load-Crack Mouth Opening Displacement and Durability.

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4550 Analysis of the Gait Characteristics of Soldier between the Normal and Loaded Gait

Authors: Ji-il Park, Min Kyu Yu, Jong-woo Lee, Sam-hyeon Yoo

Abstract:

The purpose of this research is to analyze the gait strategy between the normal and loaded gait. To this end, five male participants satisfied two conditions: the normal and loaded gait (backpack load 25.2 kg). As expected, results showed that additional loads elicited not a proportional increase in vertical and shear ground reaction force (GRF) parameters but also increase of the impulse, momentum and mechanical work. However, in case of the loaded gait, the time duration of the double support phase was increased unexpectedly. It is because the double support phase which is more stable than the single support phase can reduce instability of the loaded gait. Also, the directions of the pre-collision and after-collision were moved upward and downward compared to the normal gait. As a result, regardless of the additional backpack load, the impulse-momentum diagram during the step-to-step transition was maintained such as the normal gait. It means that human walk efficiently to keep stability and minimize total net works in case of the loaded gait.

Keywords: Normal gait, loaded gait, impulse, collision, gait analysis, mechanical work, backpack load.

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4549 Mechanical Properties of Powder Metallurgy Processed Biodegradable Zn-Based Alloy for Biomedical Application

Authors: Maruf Yinka Kolawole, Jacob Olayiwola Aweda, Farasat Iqbal, Asif Ali, Sulaiman Abdulkareem

Abstract:

Zinc is a non-ferrous metal with potential application in orthopaedic implant materials. However, its poor mechanical properties were major challenge to its application. Therefore, this paper studies the mechanical properties of biodegradable Zn-based alloy for biomedical application. Pure zinc powder with varying (0, 1, 2, 3 & 6) wt% of magnesium powders were ball milled using ball-to-powder ratio (B:P) of 10:1 at 350 rpm for 4 hours. The resulting milled powders were compacted and sintered at 300 MPa and 350 °C respectively. Microstructural, phase and mechanical properties analyses were performed following American standard of testing and measurement. The results show that magnesium has influence on the mechanical properties of zinc. The compressive strength, hardness and elastic modulus of 210 ± 8.878 MPa, 76 ± 5.707 HV and 45 ± 11.616 GPa respectively as obtained in Zn-2Mg alloy were optimum and meet the minimum requirement of biodegradable metal for orthopaedics application. These results indicate an increase of 111, 93 and 93% in compressive strength, hardness and elastic modulus respectively as compared to pure zinc. The increase in mechanical properties was adduced to effectiveness of compaction pressure and intermetallic phase formation within the matrix resulting in high dislocation density for improving strength. The study concluded that, Zn-2Mg alloy with optimum mechanical properties can therefore be considered a potential candidate for orthopaedic application.

Keywords: Biodegradable metal, biomedical application mechanical properties, powder metallurgy, zinc.

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4548 Performance of an Electrocoagulation Process in Treating Direct Dye: Batch and Continuous Upflow Processes

Authors: C. Phalakornkule, S. Polgumhang, W. Tongdaung

Abstract:

This study presents an investigation of electrochemical variables and an application of the optimal parameters in operating a continuous upflow electrocoagulation reactor in removing dye. Direct red 23, which is azo-based, was used as a representative of direct dyes. First, a batch mode was employed to optimize the design parameters: electrode type, electrode distance, current density and electrocoagulation time. The optimal parameters were found to be iron anode, distance between electrodes of 8 mm and current density of 30 A·m-2 with contact time of 5 min. The performance of the continuous upflow reactor with these parameters was satisfactory, with >95% color removal and energy consumption in the order of 0.6-0.7 kWh·m-3.

Keywords: Decolorization, Direct Dye, Electrocoagulation, Textile Wastewater, Upflow Reactor.

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