Search results for: Non linear process
1534 Numerical Study of a Butterfly Valve for Vibration Analysis and Reduction
Authors: Malik I. Al-Amayreh, Mohammad I. Kilani, Ahmed S. Al-Salaymeh
Abstract:
This work presents a Computational Fluid Dynamics (CFD) simulation of a butterfly valve used to control the flow of combustible gas mixture in an industrial process setting.The work uses CFD simulation to analyze the flow characteristics in the vicinity of the valve, including the pressure distributions and Frequency spectrum of the pressure pulsations downstream the valves and the vortex shedding allow predicting the torque fluctuations acting on the valve shaft and the possibility of generating mechanical vibration and resonance.These fluctuations are due to aerodynamic torque resulting from fluid turbulence and vortex shedding in the valve vicinity. The valve analyzed is located in a pipeline between two opposing 90o elbows, which exposes the valve and the surrounding structure to the turbulence generated upstream and downstream the elbows at either end of the pipe.CFD simulations show that the best location for the valve from a vibration point of view is in the middle of the pipe joining the elbows.
Keywords: Butterfly Valve Vibration Analysis, Computational Fluid Dynamics, Fluid Flow Circuit Design, Fluid Mechanics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 38201533 The Key Challenges of the New Bank Regulations
Authors: Petr Teply
Abstract:
The New Basel Capital Accord (Basel II) influences how financial institutions around the world, and especially European Union institutions, determine the amount of capital to reserve. However, as the recent global crisis has shown, the revision of Basel II is needed to reflect current trends, such as increased volatility and correlation, in the world financial markets. The overall objective of Basel II is to increase the safety and soundness of the international financial system. Basel II builds on three main pillars: Pillar I deals with the minimum capital requirements for credit, market and operational risk, Pillar II focuses on the supervisory review process and finally Pillar III promotes market discipline through enhanced disclosure requirements for banks. The aim of this paper is to provide the historical background, key features and impact of Basel II on financial markets. Moreover, we discuss new proposals for international bank regulation (sometimes referred to as Basel III) which include requirements for higher quality, constituency and transparency of banks' capital and risk management, regulation of OTC markets and introduction of new liquidity standards for internationally active banks.
Keywords: Basel II, Basel III, risk management, bank regulation
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20771532 Logistic and Its Importance in Turkish Food Sector and an Analysis of the Logistics Sector in Turkey
Authors: Şule Turhan, Özlem Turan
Abstract:
Permanence in the international markets for many global companies is about being known as having effective logistics which targets customer satisfaction management and lower costs. Under competitive conditions, the necessity of providing the products to customers quickly and on time for the companies which constantly aim to improve their profitability increased the strategic importance of the logistics concept. Food logistic is one of the most difficult areas in logistics. In the process from manufacturer to final consumer, quality and hygiene standards must be provided constantly. In food logistics, reliable and extensive service network has great importance and on time delivery is the target. Developing logistics industry provide the supply of foods in the country and the development of export markets more quickly and has an important role in providing added value to the country's economy. Turkey that creates a bridge between the east and the west is an attractive market for logistics companies. In this study, by examining both the place and the importance of logistics in Turkish food sector, recommendations will be made for the food industry.Keywords: Logistics, Turkish food industry, competition, food industry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13381531 CFD Analysis of a Centrifugal Fan for Performance Enhancement using Converging Boundary Layer Suction Slots
Authors: K. Vasudeva Karanth, N. Yagnesh Sharma
Abstract:
Generally flow behavior in centrifugal fan is observed to be in a state of instability with flow separation zones on suction surface as well as near the front shroud. Overall performance of the diffusion process in a centrifugal fan could be enhanced by judiciously introducing the boundary layer suction slots. With easy accessibility of CFD as an analytical tool, an extensive numerical whole field analysis of the effect of boundary layer suction slots in discrete regions of suspected separation points is possible. This paper attempts to explore the effect of boundary layer suction slots corresponding to various geometrical locations on the impeller with converging configurations for the slots. The analysis shows that the converging suction slots located on the impeller blade about 25% from the trailing edge, significantly improves the static pressure recovery across the fan. Also it is found that Slots provided at a radial distance of about 12% from the leading and trailing edges marginally improve the static pressure recovery across the fan.Keywords: Boundary layer suction converging slot, Flowseparation, Sliding mesh, Unsteady analysis, Recirculation zone, Jetsand wakes.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30251530 Behavior of Generated Gas in Lost Foam Casting
Authors: M. Khodai, S. M. H. Mirbagheri
Abstract:
In the Lost Foam Casting process, melting point temperature of metal, as well as volume and rate of the foam degradation have significant effect on the mold filling pattern. Therefore, gas generation capacity and gas gap length are two important parameters for modeling of mold filling time of the lost foam casting processes. In this paper, the gas gap length at the liquidfoam interface for a low melting point (aluminum) alloy and a high melting point (Carbon-steel) alloy are investigated by the photography technique. Results of the photography technique indicated, that the gas gap length and the mold filling time are increased with increased coating thickness and density of the foam. The Gas gap lengths measured in aluminum and Carbon-steel, depend on the foam density, and were approximately 4-5 and 25-60 mm, respectively. By using a new system, the gas generation capacity for the aluminum and steel was measured. The gas generation capacity measurements indicated that gas generation in the Aluminum and Carbon-steel lost foam casting was about 50 CC/g and 3200 CC/g polystyrene, respectively.Keywords: gas gap, lost foam casting, photographytechnique.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35051529 An Improved Quality Adaptive Rate Filtering Technique Based on the Level Crossing Sampling
Authors: Saeed Mian Qaisar, Laurent Fesquet, Marc Renaudin
Abstract:
Mostly the systems are dealing with time varying signals. The Power efficiency can be achieved by adapting the system activity according to the input signal variations. In this context an adaptive rate filtering technique, based on the level crossing sampling is devised. It adapts the sampling frequency and the filter order by following the input signal local variations. Thus, it correlates the processing activity with the signal variations. Interpolation is required in the proposed technique. A drastic reduction in the interpolation error is achieved by employing the symmetry during the interpolation process. Processing error of the proposed technique is calculated. The computational complexity of the proposed filtering technique is deduced and compared to the classical one. Results promise a significant gain of the computational efficiency and hence of the power consumption.Keywords: Level Crossing Sampling, Activity Selection, Rate Filtering, Computational Complexity, Interpolation Error.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15611528 Using Multi-Linguistic Techniques for Thailand Herb and Traditional Medicine Registration Systems
Authors: Thanapol Wisuttikul, Choochart Haruechaiyasak, Santipong Thaiprayoon
Abstract:
Thailand has evolved many unique culture and knowledge, and the leading is the Thai traditional medicine (TTM). Recently, a number of researchers have tried to save this indigenous knowledge. However, the system to do so has still been scant. To preserve this ancient knowledge, we therefore invented and integrated multi-linguistic techniques to create the system of the collected all of recipes. This application extracted the medical recipes from antique scriptures then normalized antiquarian words, primitive grammar and antiquated measurement of them to the modern ones. Then, we applied ingredient-duplication-calculation, proportion-similarity-calculation and score-ranking to examine duplicate recipes. We collected the questionnaires from registrants and people to investigate the users’ satisfaction. The satisfactory results were found. This application assists not only registrants to validating the copyright violation in TTM registration process but also people to cure their illness that aids both Thai people and all mankind to fight for intractable diseases.
Keywords: Medicine Registration, Search Engine, Text Approximation, Traditional Medicine.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20151527 Multi-Disciplinary Optimisation Methodology for Aircraft Load Prediction
Authors: Sudhir Kumar Tiwari
Abstract:
The paper demonstrates a methodology that can be used at an early design stage of any conventional aircraft. This research activity assesses the feasibility derivation of methodology for aircraft loads estimation during the various phases of design for a transport category aircraft by utilizing potential of using commercial finite element analysis software, which may drive significant time saving. Early Design phase have limited data and quick changing configuration results in handling of large number of load cases. It is useful to idealize the aircraft as a connection of beams, which can be very accurately modelled using finite element analysis (beam elements). This research explores the correct approach towards idealizing an aircraft using beam elements. FEM Techniques like inertia relief were studied for implementation during course of work. The correct boundary condition technique envisaged for generation of shear force, bending moment and torque diagrams for the aircraft. The possible applications of this approach are the aircraft design process, which have been investigated.
Keywords: Multi-disciplinary optimization, aircraft load, finite element analysis, Stick Model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11371526 Enhancement of Visual Comfort Using Parametric Double Skin Façades
Authors: Ahmed Ashraf Khamis, Sherif A. Ibrahim, Mahmoud ElKhatieb, Mohamed A. Barakat
Abstract:
Parametric design deemed to be one of icons of the modern architectural trends that facilitates taking complex design decisions counting on altering various design parameters. Double skin façades are one of the parametric applications that are used in parametric designs. This paper opts to enhance different daylight parameters of a selected case study office building in Cairo using a parametric double skin façade. First, the design and optimization process was executed utilizing Grasshopper parametric design software package, in which the daylighting performance of the base case building model was compared with the one used in the double façade showing an enhancement in task plane illuminance by 180%. Second, execution drawings are made for the optimized design using Revit software. Finally, computerized digital fabrication stages of the designed model with various scales are demonstrated to reach the final design decisions using Simplify 3D for mock-up digital fabrication.
Keywords: Parametric design, Double skin façades, Digital Fabrication, Grasshopper, Simplify 3D.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3551525 Probabilistic Electrical Power Generation Modeling Using Decimal to Binary Conversion
Authors: Ahmed S. Al-Abdulwahab
Abstract:
Generation system reliability assessment is an important task which can be performed using deterministic or probabilistic techniques. The probabilistic approaches have significant advantages over the deterministic methods. However, more complicated modeling is required by the probabilistic approaches. Power generation model is a basic requirement for this assessment. One form of the generation models is the well known capacity outage probability table (COPT). Different analytical techniques have been used to construct the COPT. These approaches require considerable mathematical modeling of the generating units. The unit-s models are combined to build the COPT which will add more burdens on the process of creating the COPT. Decimal to Binary Conversion (DBC) technique is widely and commonly applied in electronic systems and computing This paper proposes a novel utilization of the DBC to create the COPT without engaging in analytical modeling or time consuming simulations. The simple binary representation , “0 " and “1 " is used to model the states o f generating units. The proposed technique is proven to be an effective approach to build the generation model.Keywords: Decimal to Binary, generation, reliability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20441524 Pyrolysis Characteristics and Kinetics of Macroalgae Biomass Using Thermogravimetric Analyzer
Authors: Zhao Hui, Yan Huaxiao, Zhang Mengmeng, Qin Song
Abstract:
The pyrolysis characteristics and kinetics of seven marine biomass, which are fixed Enteromorpha clathrata, floating Enteromorpha clathrata, Ulva lactuca L., Zosterae Marinae L., Thallus Laminariae, Asparagus schoberioides kunth and Undaria pinnatifida (Harv.), were studied with thermogravimetric analysis method. Simultaneously, cornstalk, which is a grass biomass, and sawdust, which is a lignocellulosic biomass, were references. The basic pyrolysis characteristics were studied by using TG- DTG-DTA curves. The results showed that there were three stages (dehydration, dramatic weight loss and slow weight loss) during the whole pyrolysis process of samples. The Tmax of marine biomass was significantly lower than two kinds of terrestrial biomass. Zosterae Marinae L. had a relatively high stability of pyrolysis, but floating Enteromorpha clathrata had lowest stability of pyrolysis and a good combustion characteristics. The corresponding activation energy E and frequency factor A were obtained by Coats-Redfern method. It was found that the pyrolysis reaction mechanism functions of three kinds of biomass are different.
Keywords: macroalgae biomass, pyrolysis, thermogravimetric analysis, thermolysis kinetics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27421523 Enhancement in a Mechatronic Aluminum Beverage Cans Recycling Machine
Authors: H. M. El-Zomor, M. Hany
Abstract:
Recycling of aluminum beverage cans is an important issue due to its economic and environmental effect. One of the significant factors in aluminum cans recycling process is the transportation cost from the landfill space. An automatic compression baler (ACB) machine has been designed and built to densify the aluminum beverage cans. It has been constructed using numerous fabricated components. Two types of control methodology have been introduced in this ACB machine to achieve its goal. The first is a semi-automatic system, and the second is a mechatronic system by using a Programmable Logic Control (PLC). The effect of single and double pre-compression for the beverage cans have been evaluated by using the PLC control. Comparisons have been performed between the two types of control methodologies by operating this ACB machine in different working conditions. The double pre-compression in PLC control proves that there is an enhancement in the ACB performance by 133% greater than the direct compression in the semi-automatic control. In addition, the percentage of the reduction ratio in volume reaches 77%, and the compaction ratio reaches about four times of the initial volume.
Keywords: Aluminum can recycling, Fully automatic machine, Hydraulic system control, Multi-compression.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25861522 DocPro: A Framework for Processing Semantic and Layout Information in Business Documents
Authors: Ming-Jen Huang, Chun-Fang Huang, Chiching Wei
Abstract:
With the recent advance of the deep neural network, we observe new applications of NLP (natural language processing) and CV (computer vision) powered by deep neural networks for processing business documents. However, creating a real-world document processing system needs to integrate several NLP and CV tasks, rather than treating them separately. There is a need to have a unified approach for processing documents containing textual and graphical elements with rich formats, diverse layout arrangement, and distinct semantics. In this paper, a framework that fulfills this unified approach is presented. The framework includes a representation model definition for holding the information generated by various tasks and specifications defining the coordination between these tasks. The framework is a blueprint for building a system that can process documents with rich formats, styles, and multiple types of elements. The flexible and lightweight design of the framework can help build a system for diverse business scenarios, such as contract monitoring and reviewing.
Keywords: Document processing, framework, formal definition, machine learning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6461521 Performance Evaluation of Purely Mechanical Wireless In-Mould Sensor for Injection Moulding
Authors: Florian Müller, Christian Kukla, Thomas Lucyshyn, Clemens Holzer
Abstract:
In this paper, the influencing parameters of a novel purely mechanical wireless in-mould injection moulding sensor were investigated. The sensor is capable of detecting the melt front at predefined locations inside the mould. The sensor comprises a movable pin which acts as the sensor element generating structure-borne sound triggered by the passing melt front. Due to the sensor design, melt pressure is the driving force. For pressure level measurement during pin movement a pressure transducer located at the same position as the movable pin. By deriving a mathematical model for the mechanical movement, dominant process parameters could be investigated towards their impact on the melt front detection characteristic. It was found that the sensor is not affected by the investigated parameters enabling it for reliable melt front detection. In addition, it could be proved that the novel sensor is in comparable range to conventional melt front detection sensors.
Keywords: Injection Moulding, In-Mould Sensor, Structure-Borne Sound, Wireless Sensor
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20731520 The Effects of Methionine and Acetate Concentrations on Mycophenolic Acid Production by Penicillium bervicompactum MUCL 19011 in Submerged Culture
Authors: F. Ardestani, S.A. Fatemi, B. Yakhchali, M. Hosseyni, G. Najafpour
Abstract:
Mycophenolic acid “MPA" is a secondary metabolite of Penicillium bervicompactum with antibiotic and immunosuppressive properties. In this study, fermentation process was established for production of mycophenolic acid by Penicillium bervicompactum MUCL 19011 in shake flask. The maximum MPA production, product yield and productivity were 1.379 g/L, 18.6 mg/g glucose and 4.9 mg/L.h respectively. Glucose consumption, biomass and MPA production profiles were investigated during fermentation time. It was found that MPA production starts approximately after 180 hours and reaches to a maximum at 280 h. In the next step, the effects of methionine and acetate concentrations on MPA production were evaluated. Maximum MPA production, product yield and productivity (1.763 g/L, 23.8 mg/g glucose and 6.30 mg/L. h respectively) were obtained with using 2.5 g/L methionine in culture medium. Further addition of methionine had not more positive effect on MPA production. Finally, results showed that the addition of acetate to the culture medium had not any observable effect on MPA production.Keywords: Penicillium bervicompactum, Methionine, Mycophenolic acid, Submerged culture
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14991519 Developing the Personal, Dissolving the Political
Authors: James Moir
Abstract:
The emergence of person-centred discourse based around notions of 'personal development planning- and 'work'life balance' has taken hold in education and the workplace in recent years. This paper examines this discourse with regard to recent developments in higher education as well as the inter-related issue of work-life balance in occupational careers. In both cases there have been national and trans-national policy initiatives directed towards improving both personal opportunities and competitive advantage in a global knowledge-based economy. However, despite an increasing concern with looking outward at this globalised educational and employment marketplace, there is something of a paradox in encouraging people to look inward at themselves in order to become more self-determined. This apparent paradox is considered from a discourse analytic perspective in terms of the ideological effects of an increasing concern with the personal world. Specifically, it is argued that there are tensions that emerge from a concern with an innerdirected process of self-reflection that dissolve any engagement with wider political issues that impact upon educational and career development.Keywords: Personal development planning, higher education, work-life balance, career.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14061518 3D Numerical Simulation of Scouring around Bridge Piers (Case Study: Bridge 524 Crosses the Tanana River)
Authors: T. Esmaeili, A. A. Dehghani, A. R. Zahiri, K. Suzuki
Abstract:
Due to the three- dimensional flow pattern interacting with bed material, the process of local scour around bridge piers is complex. Modeling 3D flow field and scour hole evolution around a bridge pier is more feasible nowadays because the computational cost and computational time have significantly decreased. In order to evaluate local flow and scouring around a bridge pier, a completely three-dimensional numerical model, SSIIM program, was used. The model solves 3-D Navier-Stokes equations and a bed load conservation equation. The model was applied to simulate local flow and scouring around a bridge pier in a large natural river with four piers. Computation for 1 day of flood condition was carried out to predict the maximum local scour depth. The results show that the SSIIM program can be used efficiently for simulating the scouring in natural rivers. The results also showed that among the various turbulence models, the k-ω model gives more reasonable results.
Keywords: Bridge piers, flood, numerical simulation, SSIIM.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29081517 Experimental Investigation of a Novel Reaction in Reduction of Sulfates by Natural Gas as a Reducing Agent
Authors: Ali Ghiaseddin , Akram Nemati
Abstract:
In a pilot plant scale of a fluidized bed reactor, a reduction reaction of sodium sulfate by natural gas has been investigated. Natural gas is applied in this study as a reductant. Feed density, feed mass flow rate, natural gas and air flow rate (independent parameters)and temperature of bed and CO concentration in inlet and outlet of reactor (dependent parameters) were monitored and recorded at steady state. The residence time was adjusted close to value of traditional reaction [1]. An artificial neural network (ANN) was established to study dependency of yield and carbon gradient on operating parameters. Resultant 97% accuracy of applied ANN is a good prove that natural gas can be used as a reducing agent. Predicted ANN model for relation between other sources carbon gradient (accuracy 74%) indicates there is not a meaningful relation between other sources carbon variation and reduction process which means carbon in granule does not have significant effect on the reaction yield.Keywords: reduction by natural gas, fluidized bed, sulfate, sulfide, artificial neural network
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15271516 Design of Service-Oriented Pervasive System for Urban Computing in Cali Zoo (OpenZoo)
Authors: Claudia L. Zuñiga, Andres F. Millan, Jose L. Abadia, Monica Lora, Andres Navarro, Juan C. Burguillo, Pedro S. Rodriguez
Abstract:
The increasing popularity of wireless technologies and mobile computing devices has enabled new application areas and research. One of these new areas is pervasive systems in urban environments, because urban environments are characterized by high concentration of these technologies and devices. In this paper we will show the process of pervasive system design in urban environments, using as use case a local zoo in Cali, Colombia. Based on an ethnographic studio, we present the design of a pervasive system for urban computing based on service oriented architecture to controlled environment of Cali Zoo. In this paper, the reader will find a methodological approach for the design of similar systems, using data collection methods, conceptual frameworks for urban environments and considerations of analysis and design of service oriented systems.Keywords: Service Oriented Architecture, Urban Computing, Design of pervasive systems for urban environments, PSP Design Framework (Public Social Private), Cali Zoo.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15611515 Simulation of the Performance of the Reforming of Methane in a Primary Reformer
Authors: A. Alkattib, M. Boumaza
Abstract:
Steam reforming is industrially important as it is incorporated in several major chemical processes including the production of ammonia, methanol, hydrogen and ox alcohols. Due to the strongly endothermic nature of the process, a large amount of heat is supplied by fuel burning (commonly natural gas) in the furnace chamber. Reaction conversions, tube catalyst life, energy consumption and CO2 emission represent the principal factors affecting the performance of this unit and are directly influenced by the high operating temperatures and pressures. This study presents a simulation of the performance of the reforming of methane in a primary reformer, through a developed empirical relation which enables to investigate the effects of operating parameters such as the pressure, temperature, steam to carbon ratio on the production of hydrogen, as well as the fraction of non converted methane. It appears from this analysis that the exit temperature Te, the operating pressure as well the steam to carbon ratio has an important effect on the reforming of methane.
Keywords: Reforming, methane, performance, hydrogen, parameters.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24731514 Measuring Cognitive Load - A Solution to Ease Learning of Programming
Authors: Muhammed Yousoof, Mohd Sapiyan, Khaja Kamaluddin
Abstract:
Learning programming is difficult for many learners. Some researches have found that the main difficulty relates to cognitive load. Cognitive overload happens in programming due to the nature of the subject which is intrinisicly over-bearing on the working memory. It happens due to the complexity of the subject itself. The problem is made worse by the poor instructional design methodology used in the teaching and learning process. Various efforts have been proposed to reduce the cognitive load, e.g. visualization softwares, part-program method etc. Use of many computer based systems have also been tried to tackle the problem. However, little success has been made to alleviate the problem. More has to be done to overcome this hurdle. This research attempts at understanding how cognitive load can be managed so as to reduce the problem of overloading. We propose a mechanism to measure the cognitive load during pre instruction, post instruction and in instructional stages of learning. This mechanism is used to help the instruction. As the load changes the instruction is made to adapt itself to ensure cognitive viability. This mechanism could be incorporated as a sub domain in the student model of various computer based instructional systems to facilitate the learning of programming.
Keywords: Cognitive load, Working memory, Cognitive Loadmeasurement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25651513 Microwave Sintering and Its Application on Cemented Carbides
Authors: Rumman Md Raihanuzzaman, Lee Chang Chuan, Zonghan Xie, Reza Ghomashchi
Abstract:
Cemented carbides, owing to their excellent mechanical properties, have been of immense interest in the field of hard materials for the past few decades. A number of processing techniques have been developed to obtain high quality carbide tools, with a wide range of grain size depending on the application and requirements. Microwave sintering is one of the heating processes, which has been used to prepare a wide range of materials including ceramics. A deep understanding of microwave sintering and its contribution towards control of grain growth and on deformation of the resulting carbide materials requires further studies and attention. In addition, the effect of binder materials and their behavior during microwave sintering is another area that requires clear understanding. This review aims to focus on microwave sintering, providing information of how the process works and what type of materials it is best suited for. In addition, a closer look at some microwave sintered Tungsten Carbide-Cobalt samples will be taken and discussed, highlighting some of the key issues and challenges faced in this research area.Keywords: Cemented carbides, consolidation, microwave sintering, mechanical properties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29231512 Citizens’ Perceptions towards e-Governance: Field Study
Authors: Alaa-Aldin Abdul Rahim A. Al Athmay
Abstract:
E-governance is an emerging and challenging initiative in developing countries. It is not only concerning the provision of services through the use ICT but rather entails building external interactions with citizen and businesses, enhancing democracy and trust of the political institutions of government. It embraces among other principles, openness, accountability and citizen engagement in public policy process. This study aims at finding users’ satisfaction with three chosen dimensions of e-governance, namely: openness, collaborative governance, and participation. These dimensions of e-governance are neither studied before in the context of Arab countries and nor explored earlier in relation to some demographics variables. A study of 900 users of e-government in United Arab Emirates (UAE) was undertaken to examine how gender, age, education, nationality, and employment affect their satisfaction with e-governance. Generally, satisfaction ratings vary significantly with these variables. However, the overall level of satisfaction with the three attributes was less favorable. Knowing the differences of citizen’s perceptions towards e-governance services would help policymakers in the design of effective e-governance strategy.
Keywords: E-governance, United Arab Emirates, Citizens' perceptions.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 46221511 Tool Failure Detection Based on Statistical Analysis of Metal Cutting Acoustic Emission Signals
Authors: Othman Belgassim, Krzysztof Jemielniak
Abstract:
The analysis of Acoustic Emission (AE) signal generated from metal cutting processes has often approached statistically. This is due to the stochastic nature of the emission signal as a result of factors effecting the signal from its generation through transmission and sensing. Different techniques are applied in this manner, each of which is suitable for certain processes. In metal cutting where the emission generated by the deformation process is rather continuous, an appropriate method for analysing the AE signal based on the root mean square (RMS) of the signal is often used and is suitable for use with the conventional signal processing systems. The aim of this paper is to set a strategy in tool failure detection in turning processes via the statistic analysis of the AE generated from the cutting zone. The strategy is based on the investigation of the distribution moments of the AE signal at predetermined sampling. The skews and kurtosis of these distributions are the key elements in the detection. A normal (Gaussian) distribution has first been suggested then this was eliminated due to insufficiency. The so called Beta distribution was then considered, this has been used with an assumed β density function and has given promising results with regard to chipping and tool breakage detection.Keywords: AE signal, skew, kurtosis, tool failure
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18511510 Surface Roughness Evaluation for EDM of En31 with Cu-Cr-Ni Powder Metallurgy Tool
Authors: Amoljit S. Gill, Sanjeev Kumar
Abstract:
In this study, Electrical Discharge Machining (EDM) is used to modify the surface of high carbon steel En31 with the help of tool electrode (Copper-Chromium-Nickel) manufactured by powder metallurgy (PM) process. The effect of EDM on surface roughness during surface alloying is studied. Taguchi’s Design of experiment (DOE) and L18 orthogonal array is used to find the best level of input parameters in order to achieve high surface finish. Six input parameters are considered and their percentage contribution towards surface roughness is investigated by analysis of variances (ANOVA). Experimental results show that an hard alloyed surface (1.21% carbon, 2.14% chromium and 1.38% nickel) with surface roughness of 3.19µm can be generated using EDM with PM tool. Additionally, techniques like Scanning Electron Microscope (SEM) and Energy Dispersive Spectroscopy (EDS) are used to analyze the machined surface and EDMed layer composition, respectively. The increase in machined surface micro-hardness (101%) may be related to the formation of carbides containing chromium.
Keywords: Electrical Discharge Machining, Surface Roughness, Powder metallurgy compact tools, Taguchi DOE technique.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28761509 Degraded Document Analysis and Extraction of Original Text Document: An Approach without Optical Character Recognition
Authors: L. Hamsaveni, Navya Prakash, Suresha
Abstract:
Document Image Analysis recognizes text and graphics in documents acquired as images. An approach without Optical Character Recognition (OCR) for degraded document image analysis has been adopted in this paper. The technique involves document imaging methods such as Image Fusing and Speeded Up Robust Features (SURF) Detection to identify and extract the degraded regions from a set of document images to obtain an original document with complete information. In case, degraded document image captured is skewed, it has to be straightened (deskew) to perform further process. A special format of image storing known as YCbCr is used as a tool to convert the Grayscale image to RGB image format. The presented algorithm is tested on various types of degraded documents such as printed documents, handwritten documents, old script documents and handwritten image sketches in documents. The purpose of this research is to obtain an original document for a given set of degraded documents of the same source.Keywords: Grayscale image format, image fusing, SURF detection, YCbCr image format.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11591508 Comparison of Different Neural Network Approaches for the Prediction of Kidney Dysfunction
Authors: Ali Hussian Ali AlTimemy, Fawzi M. Al Naima
Abstract:
This paper presents the prediction of kidney dysfunction using different neural network (NN) approaches. Self organization Maps (SOM), Probabilistic Neural Network (PNN) and Multi Layer Perceptron Neural Network (MLPNN) trained with Back Propagation Algorithm (BPA) are used in this study. Six hundred and sixty three sets of analytical laboratory tests have been collected from one of the private clinical laboratories in Baghdad. For each subject, Serum urea and Serum creatinin levels have been analyzed and tested by using clinical laboratory measurements. The collected urea and cretinine levels are then used as inputs to the three NN models in which the training process is done by different neural approaches. SOM which is a class of unsupervised network whereas PNN and BPNN are considered as class of supervised networks. These networks are used as a classifier to predict whether kidney is normal or it will have a dysfunction. The accuracy of prediction, sensitivity and specificity were found for each type of the proposed networks .We conclude that PNN gives faster and more accurate prediction of kidney dysfunction and it works as promising tool for predicting of routine kidney dysfunction from the clinical laboratory data.Keywords: Kidney Dysfunction, Prediction, SOM, PNN, BPNN, Urea and Creatinine levels.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19361507 3D Guidance of Unmanned Aerial Vehicles Using Sliding Mode Approach
Authors: M. Zamurad Shah, M. Kemal Özgören, Raza Samar
Abstract:
This paper presents a 3D guidance scheme for Unmanned Aerial Vehicles (UAVs). The proposed guidance scheme is based on the sliding mode approach using nonlinear sliding manifolds. Generalized 3D kinematic equations are considered here during the design process to cater for the coupling between longitudinal and lateral motions. Sliding mode based guidance scheme is then derived for the multiple-input multiple-output (MIMO) system using the proposed nonlinear manifolds. Instead of traditional sliding surfaces, nonlinear sliding surfaces are proposed here for performance and stability in all flight conditions. In the reaching phase control inputs, the bang-bang terms with signum functions are accompanied with proportional terms in order to reduce the chattering amplitudes. The Proposed 3D guidance scheme is implemented on a 6-degrees-of-freedom (6-dof) simulation of a UAV and simulation results are presented here for different 3D trajectories with and without disturbances.
Keywords: Unmanned Aerial Vehicles, Sliding mode control, 3D Guidance, Path following, trajectory tracking, nonlinear sliding manifolds.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27071506 Design and Analysis of a Piezoelectric-Based AC Current Measuring Sensor
Authors: Easa Ali Abbasi, Akbar Allahverdizadeh, Reza Jahangiri, Behnam Dadashzadeh
Abstract:
Electrical current measurement is a suitable method for the performance determination of electrical devices. There are two contact and noncontact methods in this measuring process. Contact method has some disadvantages like having direct connection with wire which may endamage the system. Thus, in this paper, a bimorph piezoelectric cantilever beam which has a permanent magnet on its free end is used to measure electrical current in a noncontact way. In mathematical modeling, based on Galerkin method, the governing equation of the cantilever beam is solved, and the equation presenting the relation between applied force and beam’s output voltage is presented. Magnetic force resulting from current carrying wire is considered as the external excitation force of the system. The results are compared with other references in order to demonstrate the accuracy of the mathematical model. Finally, the effects of geometric parameters on the output voltage and natural frequency are presented.
Keywords: Cantilever beam, electrical current measurement, forced excitation, piezoelectric.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10791505 Synthesis of ZnO Nanostructures via Gel-casting Method
Authors: A.A.Rohani, A.Salehi, M.Tabrizi, S. A. Manafi, A. Fardafshari
Abstract:
In this study, ZnO nano rods and ZnO ultrafine particles were synthesized by Gel-casting method. The synthesized ZnO powder has a hexagonal zincite structure. The ZnO aggregates with rod-like morphology are typically 1.4 μm in length and 120 nm in diameter, which consist of many small nanocrystals with diameters of 10 nm. Longer wires connected by many hexahedral ZnO nanocrystals were obtained after calcinations at the temperature over 600° C.The crystalline structures and morphologies of the powder have been characterized by X-ray diffraction(XRD) and Scaning electron microscopy (SEM).The result shows that the different preparation conditions such as concentration H2O, calcinations time and calcinations temperature have a lot of influences upon the properties of nano ZnO powders, an increase in the temperature of the calcinations results in an increase of the grain size and also the increase of the calcinations time in high temperature makes the size of the grains bigger. The existences of extra watter prevent nano grains from improving like rod morphology. We have obtained the smallest grain size of ZnO powder by controlling the process conditions. Finally In a suitable condition, a novel nanostructure, namely bi-rod-like ZnO nano rods was found which is different from known ZnO nanostructures.
Keywords: morphology, nano particles, ZnO, gel-Casting method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1775