Search results for: Effective properties
2694 Creep Constitutive Equation for 2- Materials of Weldment-304L Stainless Steel
Authors: Amir Hossein Daei Sorkhabi, Farid Vakili Tahami
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In this paper, creep constitutive equations of base (Parent) and weld materials of the weldment for cold-drawn 304L stainless steel have been obtained experimentally. For this purpose, test samples have been generated from cold drawn bars and weld material according to the ASTM standard. The creep behavior and properties have been examined for these materials by conducting uniaxial creep tests. Constant temperatures and constant load uni-axial creep tests have been carried out at two high temperatures, 680 and 720 oC, subjected to constant loads, which produce initial stresses ranging from 240 to 360 MPa. The experimental data have been used to obtain the creep constitutive parameters using numerical optimization techniques.Keywords: Creep, Constitutive equation, Cold-drawn 304L stainless steel, Weld, Base material
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27722693 The Influence of Water Ingress to Aircraft Cabin Components
Authors: Nils Ischdonat
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The accomplished study is based on the appointment and identification of ageing effects and according to this absorption of moisture of aircraft cabin components over the life-cycle. In the first step of the study ceiling panels from same age and from the same aircraft cabin have been examined according to weight changes depending on the position in the aircraft cabin. In the second step of the study different aged ceiling panels have been examined concerning deflection, weight changes and the acoustic sound transmission loss. To prove the assumption of water absorption within the study and with the theoretical background from literature and scientific papers, an older test panel was exposed extreme thermal conditions (humidity and temperature) within a climate chamber to show that there is a general ingress of water to cabin components and that this ingress of water leads to the change of different mechanical properties.Keywords: Aircraft Cabin, water ingress, ageing effects, sound transmission loss
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19762692 Process-based Business Transformation through Services Computing
Authors: Sinnakkrishnan Perumal, Nitish Pandey
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Business transformation initiatives are required by any organization to jump from its normal mode of operation to the one that is suitable for the change in the environment such as competitive pressures, regulatory requirements, changes in labor market, etc., or internal such as changes in strategy/vision, changes in the capability, change in the management, etc. Recent advances in information technology in automating the business processes have the potential to transform an organization to provide it with a sustained competitive advantage. Process constitutes the skeleton of a business. Thus, for a business to exist and compete well, it is essential for the skeleton to be robust and agile. This paper details “transformation" from a business perspective, methodologies to bring about an effective transformation, process-based transformation, and the role of services computing in this. Further, it details the benefits that could be achieved through services computing.Keywords: Business Transformation, Services Oriented Architecture, Business Processes, Process-based Transformation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21412691 Conceptual Design of Unmanned Aerial Targets
Authors: M. Adamski, J. Cwiklak
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The contemporary battlefield creates a demand for more costly and highly advanced munitions. Training personnel responsible for operations as well as immediate execution of combat tasks which engage real asset is unrealistic and economically not feasible. Owing to a wide array of exploited simulators and various types of imitators, it is possible to reduce the costs. One of the effective elements of training, which can be applied in the training of all service branches, is imitator of aerial targets. This research serves as an introduction to the commencement of design analysis over a real aerial target imitator. Within the project, the basic aerodynamic calculations were made, which enabled to determine its geometry, design layout, performance as well as mass balance of individual components. The conducted calculations of the parameters of flight characteristics come closer to the real performance of such Unmanned Aerial Vehicles.Keywords: Aerial target, aerodynamics, imitator, performance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19022690 Changes of in vitro Cytokine Production induced by δ-Lactams
Authors: Y. Baba hamed, A. Medjdoub, H. Merzouk, M. Narce
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The aim of this work was to study the in vitro effects of δ-lactam 1 and its 4-chlorophenyl derivative 2, on the proliferative responses of human lymphocytes and Th1 and Th2 cytokine secretion. The possible protective role of vitamin E on intracellular stress oxidative induced by these compounds was also investigated. Peripheral blood lymphocytes were isolated using differential centrifugation on a density gradient of Histopaque. They were cultured with mitogen concanavalin A, vitamin E (10 μM) and with different concentrations of the compounds 1 and 2 (0.1 to 10 μM). Proliferation (MTT assay), IL-2, INFγ and IL-4 (Elisa kits), intracellular superoxide anion were determined. 1 and 2 were immunostimulant and increased cytokine secretion with a shift away from Th1 response to Th2. These properties were however accompanied by an increase in intracellular oxidative stress. The presence of vitamin E exhibited protective effects by reducing δ- lactam-induced superoxide anion generation in lymphocytes.Keywords: Cytokines, δ-Lactams, In vitro Lymphocyte Proliferation, Superoxide Anion
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 38742689 Characterization of Catalagzi Fly Ash for Heavy Metal Adsorption
Authors: Nurcan Tugrul, Nil Baran Acarali, Seyma Kolemen, Emek Moroydor Derun, Sabriye Piskin
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Fly ash is a significant waste that is released of thermal power plants and defined as very fine particles that are drifted upward with up taken by the flue gases due to the burning of used coal [1]. The fly-ash is capable of removing organic contaminants in consequence of high carbon content, a large surface area per unit volume and contained heavy metals. Therefore, fly ash is used as an effective coagulant and adsorbent by pelletization [2, 3]. In this study, the possibility of use of fly ash taken from Turkey like low-cost adsorbent for adsorption of zinc ions found in waste water was investigated. The fly ash taken from Turkey was pelletized with bentonite and molass to evaluate the adsorption capaticity. For this purpose; analyses such as sieve analysis, XRD, XRF, FTIR and SEM were performed. As a result, it was seen that pellets prepared from fly ash, bentonite and molass would be used for zinc adsorption.Keywords: Fly ash, heavy metal, sieve, adsorbent.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25932688 A Hybrid Method for Determination of Effective Poles Using Clustering Dominant Pole Algorithm
Authors: Anuj Abraham, N. Pappa, Daniel Honc, Rahul Sharma
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In this paper, an analysis of some model order reduction techniques is presented. A new hybrid algorithm for model order reduction of linear time invariant systems is compared with the conventional techniques namely Balanced Truncation, Hankel Norm reduction and Dominant Pole Algorithm (DPA). The proposed hybrid algorithm is known as Clustering Dominant Pole Algorithm (CDPA), is able to compute the full set of dominant poles and its cluster center efficiently. The dominant poles of a transfer function are specific eigenvalues of the state space matrix of the corresponding dynamical system. The effectiveness of this novel technique is shown through the simulation results.
Keywords: Balanced truncation, Clustering, Dominant pole, Hankel norm, Model reduction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26872687 Effect of Oxygen and Micro-Cracking on the Flotation of Low Grade Nickel Sulphide Ore
Authors: Edison Muzenda, Ayo S Afolabi
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This study investigated the effect of oxygen and micro-cracking on the flotation of low grade nickel sulphide ore. The ore treated contained serpentine minerals which have a history of being difficult to process efficiently. The use of oxygen as a bubbling gas has been noted to be effective because it increases the pulp potential. The desired effect of micro cracking the ore is that the nickel sulphide minerals will become activated and this activation will render these minerals more susceptible to react with potassium amyl xanthate collectors, resulting in a higher recovery of nickel and hinder the recovery of other undesired minerals contained in the ore. Higher nickel recoveries were obtained when pure oxygen was used as a bubbling gas rather than the conventional air. Microwave cracking favored the recovery of nickel.Keywords: Flotation, Conventional air, Oven micro-cracking, Recovery.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21982686 HelpMeBreathe: A Web-Based System for Asthma Management
Authors: Alia Al Rayssi, Mahra Al Marar, Alyazia Alkhaili, Reem Al Dhaheri, Shayma Alkobaisi, Hoda Amer
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We present in this paper a web-based system called “HelpMeBreathe” for managing asthma. The proposed system provides analytical tools, which allow better understanding of environmental triggers of asthma, hence better support of data-driven decision making. The developed system provides warning messages to a specific asthma patient if the weather in his/her area might cause any difficulty in breathing or could trigger an asthma attack. HelpMeBreathe collects, stores, and analyzes individuals’ moving trajectories and health conditions as well as environmental data. It then processes and displays the patients’ data through an analytical tool that leads to an effective decision making by physicians and other decision makers.
Keywords: Asthma, environmental triggers, map interface, peak flow, web-based system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8692685 Energy Management Techniques in Mobile Robots
Authors: G. Gurguze, I. Turkoglu
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Today, the developing features of technological tools with limited energy resources have made it necessary to use energy efficiently. Energy management techniques have emerged for this purpose. As with every field, energy management is vital for robots that are being used in many areas from industry to daily life and that are thought to take up more spaces in the future. Particularly, effective power management in autonomous and multi robots, which are getting more complicated and increasing day by day, will improve the performance and success. In this study, robot management algorithms, usage of renewable and hybrid energy sources, robot motion patterns, robot designs, sharing strategies of workloads in multiple robots, road and mission planning algorithms are discussed for efficient use of energy resources by mobile robots. These techniques have been evaluated in terms of efficient use of existing energy resources and energy management in robots.
Keywords: Energy management, mobile robot, robot administration, robot management, robot planning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15702684 2D Fracture Analysis of the First Compression Piston Ring
Authors: I. Razmi, N. Choupani
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The incidence of mechanical fracture of an automobile piston rings prompted development of fracture analysis method on this case. The three rings (two compression rings and one oil ring) were smashed into several parts during the power-test (after manufacturing the engine) causing piston and liner to be damaged. The radial and oblique cracking happened on the failed piston rings. The aim of the fracture mechanics simulations presented in this paper was the calculation of particular effective fracture mechanics parameters, such as J-integrals and stress intensity factors. Crack propagation angles were calculated as well. Two-dimensional fracture analysis of the first compression ring has been developed in this paper using ABAQUS CAE6.5-1 software. Moreover, SEM fractography was developed on fracture surfaces and is discussed in this paper. Results of numerical calculations constitute the basis for further research on real object.Keywords: Compression piston ring, Crack, Fracture mechanics, SEM fractography.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23792683 Investigating Financial Literacy among Emiratis
Authors: Ashraf Khalil, Salam Abdallah, Khalil Al-hilo, Ebere Iroadu
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Financial literacy is one of the key factors needed in making informed financial decisions. As businesses continue to be more profit driven, more financial and economic intrigues arise that continue to put individuals at the risk of spending more and more without considering the short term and long term effects. We conducted a study to assess financial literacy and financial decision making among Emiratis. Our results show that financial literacy is lacking among Emiratis. Also, almost half of respondents owe loans to other peoples and 1/5 of them have bank loans. We expect that the outcome of this research will be useful for designing educational programs and policies to promote financial planning and security among Emiratis. We also posit that deeper and more informed understanding of this problem is a precursor for developing effective financial education programs with the aim of improving financial decision- making among Emiratis.
Keywords: Financial literacy, loans, financial planning, Emiratis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19882682 Production and Characterization of Sol-Enhanced Zn- Ni-Al2O3 Nanocomposite Coating
Authors: Soroor Ghaziof, Wei Gao
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Sol-enhanced Zn-Ni-Al2O3 nanocomposite coatings were electroplated on mild steel by our newly developed solenhanced electroplating method. In this method, transparent Al2O3 sol was added into the acidic Zn-Ni bath to produced Zn-Ni-Al2O3nanocomposite coatings. The chemical composition, microstructure and mechanical properties of the composite and alloy coatings deposited at two different agitation speed were investigated. The structure of all coatings was single γ-Ni5Zn21 phase. The composite coatings possess refined crystals with higher microhardness compared to Zn-Ni alloy coatings. The wear resistance of Zn-Ni coatings was improved significantly by incorporation of alumina nano particles into the coatings. Higher agitation speed provided more uniform coatings with smaller grain sized and slightly higher microhardness. Considering composite coatings, high agitation speeds may facilitate co-deposition of alumina in the coatings.Keywords: Microhardness, Sol-enhanced electro plating, Wear resistance, Zn-Ni-Al2O3 composite coatings.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22522681 Mathematical Model for Progressive Phase Distribution of Ku-band Reflectarray Antennas
Authors: M. Y. Ismail, M. Inam, A. F. M. Zain, N. Misran
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Progressive phase distribution is an important consideration in reflectarray antenna design which is required to form a planar wave in front of the reflectarray aperture. This paper presents a detailed mathematical model in order to determine the required reflection phase values from individual element of a reflectarray designed in Ku-band frequency range. The proposed technique of obtaining reflection phase can be applied for any geometrical design of elements and is independent of number of array elements. Moreover the model also deals with the solution of reflectarray antenna design with both centre and off-set feed configurations. The theoretical modeling has also been implemented for reflectarrays constructed on 0.508mm thickness of different dielectric substrates. The results show an increase in the slope of the phase curve from 4.61°/mm to 22.35°/mm by varying the material properties.
Keywords: Mathematical modeling, Progressive phase distribution, Reflectarray antenna, Reflection phase.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20672680 Correlation of Viscosity in Nanofluids using Genetic Algorithm-neural Network (GA-NN)
Authors: Hajir Karimi, Fakheri Yousefi, Mahmood Reza Rahimi
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An accurate and proficient artificial neural network (ANN) based genetic algorithm (GA) is developed for predicting of nanofluids viscosity. A genetic algorithm (GA) is used to optimize the neural network parameters for minimizing the error between the predictive viscosity and the experimental one. The experimental viscosity in two nanofluids Al2O3-H2O and CuO-H2O from 278.15 to 343.15 K and volume fraction up to 15% were used from literature. The result of this study reveals that GA-NN model is outperform to the conventional neural nets in predicting the viscosity of nanofluids with mean absolute relative error of 1.22% and 1.77% for Al2O3-H2O and CuO-H2O, respectively. Furthermore, the results of this work have also been compared with others models. The findings of this work demonstrate that the GA-NN model is an effective method for prediction viscosity of nanofluids and have better accuracy and simplicity compared with the others models.Keywords: genetic algorithm, nanofluids, neural network, viscosity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20852679 Computation of the Filtering Properties of Photonic Crystal Waveguide Discontinuities Using the Mode Matching Method
Authors: Athanasios Theoharidis, Thomas Kamalakis, Ioannis Neokosmidis, Thomas Sphicopoulos
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In this paper, the application of the Mode Matching (MM) method in the case of photonic crystal waveguide discontinuities is presented. The structure under consideration is divided into a number of cells, which supports a number of guided and evanescent modes. These modes can be calculated numerically by an alternative formulation of the plane wave expansion method for each frequency. A matrix equation is then formed relating the modal amplitudes at the beginning and at the end of the structure. The theory is highly efficient and accurate and can be applied to study the transmission sensitivity of photonic crystal devices due to fabrication tolerances. The accuracy of the MM method is compared to the Finite Difference Frequency Domain (FDFD) and the Adjoint Variable Method (AVM) and good agreement is observed.Keywords: Optical Communications, Integrated Optics, Photonic Crystals, Optical Waveguide Discontinuities.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15782678 Experimental Investigation on the Effect of Bond Thickness on the Interface Behaviour of Fibre Reinforced Polymer Sheet Bonded to Timber
Authors: Abbas Vahedian, Rijun Shrestha, Keith Crews
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The bond mechanism between timber and fibre reinforced polymer (FRP) is relatively complex and is influenced by a number of variables including bond thickness, bond width, bond length, material properties, and geometries. This study investigates the influence of bond thickness on the behaviour of interface, failure mode, and bond strength of externally bonded FRP-to-timber interface. In the present study, 106 single shear joint specimens have been investigated. Experiment results showed that higher layers of FRP increase the ultimate load carrying capacity of interface; conversely, such increase led to decrease the slip of interface. Moreover, samples with more layers of FRPs may fail in a brittle manner without noticeable warning that collapse is imminent.Keywords: FRP, single shear test, bond thickness, bond strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7562677 Modeling of Catalyst Deactivation in Catalytic Wet Air Oxidation of Phenol in Fixed Bed Three-Phase Reactor
Authors: Akram Golestani, Mohammad Kazemeini, Farhad Khorasheh, Moslem Fattahi
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Modeling and simulation of fixed bed three-phase catalytic reactors are considered for wet air catalytic oxidation of phenol to perform a comparative numerical analysis between tricklebed and packed-bubble column reactors. The modeling involves material balances both for the catalyst particle as well as for different fluid phases. Catalyst deactivation is also considered in a transient reactor model to investigate the effects of various parameters including reactor temperature on catalyst deactivation. The simulation results indicated that packed-bubble columns were slightly superior in performance than trickle beds. It was also found that reaction temperature was the most effective parameter in catalyst deactivation.Keywords: Catalyst deactivation, Catalytic wet air oxidation, Trickle-bed, Wastewater.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24072676 Inclusive Education of Roma Students from Socially Disadvantaged Background as a Determinant of Their Social Inclusion in the Slovak Republic
Authors: L. Horňák
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The aim of the paper is to analyze a longstanding problem in Slovakia – the effective education of Roma students coming from socially disadvantaged backgrounds. Although it is a relatively small country, there are over 630 communities in the Slovak Republic. The efficiency of the projects was verified by interviews with participants; questionnaires; and direct observations. Evaluation reports which summarized and evaluated the outcomes of the projects only confirmed their success. Slovakia realizes that appropriate social inclusion of marginalized citizens coming from the Roma ethnic group can only be achieved through education based on equality of all students and acceptance of diversity.Keywords: Inclusive education, marginalized communities, Roma student, equality in education, socially disadvantaged backgrounds, social inclusion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11442675 Influence of Fibre Content on Crack Propagation Rate in Fibre-Reinforced Concrete Beams
Authors: Amir M. Alani, Morteza Aboutalebi, Martin J. King
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Experimental study on the influence of fibre content on crack behaviour and propagation in synthetic-fibre reinforced beams has been reported in this paper. The tensile behaviour of metallic fibre concrete is evaluated in terms of residual flexural tensile strength values determined from the load-crack mouth opening displacement curve or load-deflection curve obtained by applying a centre-point load on a simply supported notched prism. The results achieved demonstrate that an increase in fibre content has an almost negligible effect on compressive and tensile splitting properties, causes a marginal increment in flexural tensile strength and increasesthe Re3 value.
Keywords: Fibre-Reinforced Concrete, Crack, Flexural Test, Ductility, Fibre Content, Experimental Study.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 37312674 Dynamic Amplification Factors of Some City Bridges
Authors: I. Paeglite, A. Paeglitis
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Paper presents a study about dynamic effects obtained from the dynamic load testing of the city highway bridges in Latvia carried out from 2005 to 2012. 9 prestressed concrete bridges and 4 composite bridges were considered. 11 of 13 bridges were designed according to the Eurocodes but two according to the previous structural codes used in Latvia (SNIP 2.05.03-84). The dynamic properties of the bridges were obtained by heavy vehicle passing the bridge roadway with different driving speeds and with or without even pavement. The obtained values of the Dynamic amplification factor (DAF) and the bridge natural frequency were analyzed and compared to the values of built-in traffic load models provided in Eurocode 1. The actual DAF values for even bridge pavement in the most cases are smaller than the value adopted in Eurocode 1. Vehicle speed for uneven pavements significantly influence Dynamic amplification factor values.
Keywords: Bridge, dynamic effects, load testing, dynamic amplification factor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30002673 Magnesium Waste Evaluation in Moderate Temperature (70oC) Magnesium Borate Synthesis
Authors: E. Moroydor Derun, A. S. Kipcak, A. Kaplan, S. Piskin
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Waste problem is becoming a future problem all over the world. Magnesium wastes which can be used in recycling processes are produced by many industrial activities. Magnesium borates which have useful properties such as; high heat resistance, corrosion resistance, supermechanical strength, superinsulation, light weight, high coefficient of elasticity and so on. Addition, magnesium borates have great potential in the development of ceramic and detergents industry, whisker-reinforced composites, antiwear, and reducing friction additives.
In this study, using the starting materials of waste magnesium and H3BO3 the hydrothermal method was applied at a moderate temperature of 70oC with different reaction times. Several reaction times of waste magnesium to H3BO3 were selected as; 30, 60, 120, 240 minutes. After the synthesis, X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) techniques were applied to products. As a result, the forms of Admontite [MgO(B2O3)3.7(H2O)] and Mcallisterite [Mg2(B6O7(OH)6)2.9(H2O)] were synthesized.
Keywords: Hydrothermal synthesis, magnesium borates, waste magnesium.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20322672 What Managers Think of Informal Networks and Knowledge Sharing by Means of Personal Networking?
Authors: Mahmood Q.K. Ghaznavi, Martin Perry, Paul Toulson, Keri Logan
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The importance of nurturing, accumulating, and efficiently deploying knowledge resources through formal structures and organisational mechanisms is well understood. Recent trends in knowledge management (KM) highlight that the effective creation and transfer of knowledge can also rely upon extra-organisational channels, such as, informal networks. The perception exists that the role of informal networks in knowledge creation and performance has been underestimated in the organisational context. Literature indicates that many managers fail to comprehend and successfully exploit the potential role of informal networks to create value for their organisations. This paper investigates: 1) whether managers share work-specific knowledge with informal contacts within and outside organisational boundaries; and 2) what do they think is the importance of this knowledge collaboration in their learning and work outcomes.
Keywords: Informal network, knowledge management, knowledge sharing, performance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21132671 Effect of Low Frequency Memory on High Power 12W LDMOS Transistors Intermodulation Distortion
Authors: A. Alghanim, J. Benedikt, P. J. Tasker
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The increasing demand for higher data rates in wireless communication systems has led to the more effective and efficient use of all allocated frequency bands. In order to use the whole bandwidth at maximum efficiency, one needs to have RF power amplifiers with a higher linear level and memory-less performance. This is considered to be a major challenge to circuit designers. In this thesis the linearity and memory are studied and examined via the behavior of the intermodulation distortion (IMD). A major source of the in-band distortion can be shown to be influenced by the out-of-band impedances presented at either the input or the output of the device, especially those impedances terminated the low frequency (IF) components. Thus, in order to regulate the in-band distortion, the out of-band distortion must be controllable. These investigations are performed on a 12W LDMOS device characterised at 2.1 GHz within a purpose built, high-power measurement system.
Keywords: Low Frequency Memory, IntermodulationDistortion (IMD).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19532670 Plate-Laminated Slotted-Waveguide Fed 2×3 Planar Inverted F Antenna Array
Authors: Badar Muneer, Waseem Shabir, Faisal Karim Shaikh
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Substrate Integrated waveguide based 6-element array of Planar Inverted F antenna (PIFA) has been presented and analyzed parametrically in this paper. The antenna is fed with coupled transverse slots on a plate laminated waveguide cavity to ensure wide bandwidth and simplicity of feeding network. The two-layer structure has one layer dedicated for feeding network and the top layer dedicated for radiating elements. It has been demonstrated that the presented feeding technique for feeding such class of array antennas can be far simple in structure and miniaturized in size when it comes to designing large phased array antenna systems. A good return loss and standing wave ratio of 2:1 has been achieved while maintaining properties of typical PIFA.
Keywords: Feeding network, laminated waveguide, PIFA, transverse slots.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9412669 Face Recognition Using Discrete Orthogonal Hahn Moments
Authors: Fatima Akhmedova, Simon Liao
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One of the most critical decision points in the design of a face recognition system is the choice of an appropriate face representation. Effective feature descriptors are expected to convey sufficient, invariant and non-redundant facial information. In this work we propose a set of Hahn moments as a new approach for feature description. Hahn moments have been widely used in image analysis due to their invariance, nonredundancy and the ability to extract features either globally and locally. To assess the applicability of Hahn moments to Face Recognition we conduct two experiments on the Olivetti Research Laboratory (ORL) database and University of Notre-Dame (UND) X1 biometric collection. Fusion of the global features along with the features from local facial regions are used as an input for the conventional k-NN classifier. The method reaches an accuracy of 93% of correctly recognized subjects for the ORL database and 94% for the UND database.Keywords: Face Recognition, Hahn moments, Recognition-by-parts, Time-lapse.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17772668 On Tarski’s Type Theorems for L-Fuzzy Isotone and L-Fuzzy Relatively Isotone Maps on L-Complete Propelattices
Authors: František Včelař, Zuzana Pátíková
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Recently a new type of very general relational structures, the so called (L-)complete propelattices, was introduced. These significantly generalize complete lattices and completely lattice L-ordered sets, because they do not assume the technically very strong property of transitivity. For these structures also the main part of the original Tarski’s fixed point theorem holds for (L-fuzzy) isotone maps, i.e., the part which concerns the existence of fixed points and the structure of their set. In this paper, fundamental properties of (L-)complete propelattices are recalled and the so called L-fuzzy relatively isotone maps are introduced. For these maps it is proved that they also have fixed points in L-complete propelattices, even if their set does not have to be of an awaited analogous structure of a complete propelattice.Keywords: Fixed point, L-complete propelattice, L-fuzzy (relatively) isotone map, residuated lattice, transitivity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11102667 Hydrolytic Properties of Ellagic Acid in Commercial Pomegranate Juices
Authors: Sibel Uzuner, Jale Acar
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Pomegranate and pomegranate juices (PJs) have taken great attention for their health benefits in the last years. As there is an increasing concern about potential health benefits of ellagic acid, it is of great interest to evaluate alterations in ellagic acid concentration of commercial PJs. The purpose of this study is to analyze total phenolic, free and total ellagic acid content of six commercial PJs sold in Turkish markets using HPLC. The results showed that some commercial PJs had markedly high total phenolic and ellagic acid content. Total phenolic substances of commercial PJs range from 796.71 to 4608.91 mg GAE/l. Free amount of ellagic acid in commercial PJs range from 27.64 to 111.78 mg/l. Samples are hydrolyzed with concentrated HCl at 93oC for 2 and 24 hour and influences of temperature and time parameters on hydrolization were investigated. Thermal processing for pasteurization increased ellagic acid via ellagitannins hydrolysis.Keywords: Ellagic acid, ellagitannin, pomegranate juice, total phenolic compounds
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22122666 A Comparison Study of Fabric Objective Measurement (FOM) Using KES-FB and PhabrOmeter System on Warp Knitted Fabrics Handle – Smoothness, Stiffness and Softness
Authors: Ka-Yan Yim, Chi-Wai Kan
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This paper conducts a comparison study using KES-FB and PhabrOmeter to measure 58 selected warp knitted fabric hand properties. Fabric samples were selected and measured by both KES-FB and PhabrOmeter. Results show differences between these two measurement methods. Smoothness and stiffness values obtained by KES-FB were found significant correlated (p value = 0.003 and 0.022) to the PhabrOmeter results while softness values between two measurement methods did not show significant correlation (p value = 0.828). Disagreements among these two measurement methods imply limitations on different mechanism principles when facing warp knitted fabrics. Subjective measurement methods and further studies are suggested in order to ascertain deeper investigation on the mechanisms of fabric hand perceptions.
Keywords: Fabric hand, fabric objective measurement, KES-FB, PhabrOmeter.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33972665 A Genetic Algorithm for Clustering on Image Data
Authors: Qin Ding, Jim Gasvoda
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Clustering is the process of subdividing an input data set into a desired number of subgroups so that members of the same subgroup are similar and members of different subgroups have diverse properties. Many heuristic algorithms have been applied to the clustering problem, which is known to be NP Hard. Genetic algorithms have been used in a wide variety of fields to perform clustering, however, the technique normally has a long running time in terms of input set size. This paper proposes an efficient genetic algorithm for clustering on very large data sets, especially on image data sets. The genetic algorithm uses the most time efficient techniques along with preprocessing of the input data set. We test our algorithm on both artificial and real image data sets, both of which are of large size. The experimental results show that our algorithm outperforms the k-means algorithm in terms of running time as well as the quality of the clustering.
Keywords: Clustering, data mining, genetic algorithm, image data.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2053