Search results for: Taguchi techniques and engineering application
Commenced in January 2007
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Edition: International
Paper Count: 15907

Search results for: Taguchi techniques and engineering application

1207 Enhancement of Material Removal Rate of Complex Featured Surfaces in Vibratory Finishing

Authors: Kunal Ahluwalia, Ampara Aramcharoen, Chan Wai Luen, Swee Hock Yeo

Abstract:

The different process engineering applications of vibratory finishing technology have led to its versatile use in the development of aviation components. The most noteworthy applications of vibratory finishing include deburring and imparting the required surface finish. In this paper, vibratory finishing has been used to study its effectiveness in removal of laser shock peened (LSP) layers from Titanium workpieces. A vibratory trough operating at a frequency of 25 Hz, amplitude 3.5 mm and titanium specimens (Ti-6Al-4V, Grade 5) of dimensions 50 x 50 x 10 mm³ were utilized for the experiments. A vibrating fixture operating at 200 Hz was used to provide vibration to the test piece and was immersed in the vibratory trough. It was evident that there is an increase in efficiency of removal of the complex featured layer and smoother surface finish with the introduction of the vibrating fixture in the vibratory finishing setup as compared to the conventional vibratory finishing setup wherein the fixture is not vibrating.

Keywords: laser shock peening, material removal, surface roughness, vibrating fixture, vibratory finishing

Procedia PDF Downloads 206
1206 Impact of Machining Parameters on the Surface Roughness of Machined PU Block

Authors: Louis Denis Kevin Catherine, Raja Aziz Raja Ma’arof, Azrina Arshad, Sangeeth Suresh

Abstract:

Machining parameters are very important in determining the surface quality of any material. In the past decade, some new engineering materials were developed for the manufacturing industry which created a need to conduct an investigation on the impact of the said parameters on their surface roughness. The polyurethane (PU) block is widely used in the automotive industry to manufacture parts such as checking fixtures that are used to verify the dimensional accuracy of automotive parts. In this paper, the design of experiment (DOE) was used to investigate the effect of the milling parameters on the PU block. Furthermore, an analysis of the machined surface chemical composition was done using scanning electron microscope (SEM). It was found that the surface roughness of the PU block is severely affected when PU undergoes a flood machining process instead of a dry condition. In addition, the step over and the silicon content were found to be the most significant parameters that influence the surface quality of the PU block.

Keywords: polyurethane (PU), design of experiment (DOE), scanning electron microscope (SEM), surface roughness

Procedia PDF Downloads 503
1205 Optimization Model for Support Decision for Maximizing Production of Mixed Fresh Fruit Farms

Authors: Andrés I. Ávila, Patricia Aros, César San Martín, Elizabeth Kehr, Yovana Leal

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Planning models for fresh products is a very useful tool for improving the net profits. To get an efficient supply chain model, several functions should be considered to get a complete simulation of several operational units. We consider a linear programming model to help farmers to decide if it is convenient to choose what area should be planted for three kinds of export fruits considering their future investment. We consider area, investment, water, productivity minimal unit, and harvest restrictions to develop a monthly based model to compute the average income in five years. Also, conditions on the field as area, water availability, and initial investment are required. Using the Chilean costs and dollar-peso exchange rate, we can simulate several scenarios to understand the possible risks associated to this market. Also, this tool help to support decisions for government and individual farmers.

Keywords: mixed integer problem, fresh fruit production, support decision model, agricultural and biosystems engineering

Procedia PDF Downloads 420
1204 A Case Study Approach to the Rate the Eco Sensitivity of Green Infrastructure Solutions

Authors: S. Saroop, D. Allopi

Abstract:

In the area of civil infrastructure, there is an urgent need to apply technologies that deliver infrastructure sustainably in a way that is cost-effective. Civil engineering projects can have a significant impact on ecological and social systems if not correctly planned, designed and implemented. It can impact climate change by addressing the issue of flooding and sustainability. Poor design choices now can result in future generations to live in a climate with depleted resources and without green spaces. The objectives of the research study were to rate the sensitivity of various greener infrastructure technologies that can be used in township infrastructure, at the various stages of the project. This paper discusses the Green Township Infrastructure Design Toolkit, that is used to rate the sustainability of infrastructure service projects. Various case studies were undertaken on a range of infrastructure projects to test the sensitivity of various design solution against sustainability criteria. The Green reporting tools ensure efficient, economical and sustainable provision of infrastructure services.

Keywords: eco-efficiency, green infrastructure, green technology, infrastructure design, sustainable development

Procedia PDF Downloads 361
1203 Understanding Mudrocks and Their Shear Strength Deterioration Associated with Inundation

Authors: Haslinda Nahazanan, Afshin Asadi, Zainuddin Md. Yusoff, Nik Nor Syahariati Nik Daud

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Mudrocks is considered as a problematic material due to their unexpected behaviour specifically when they are contacting with water or being exposed to the atmosphere. Many instability problems of cutting slopes were found lying on high slaking mudrocks. It has become one of the major concerns to geotechnical engineer as mudrocks cover up to 50% of sedimentary rocks in the geologic records. Mudrocks display properties between soils and rocks which can be very hard to understand. Therefore, this paper aims to review the definition, mineralogy, geo-chemistry, classification and engineering properties of mudrocks. As water has become one of the major factors that will rapidly change the behaviour of mudrocks, a review on the shear strength of mudrocks in Derbyshire has been made using a fully automated hydraulic stress path testing system under three states: dry, short-term inundated and long-term inundated. It can be seen that the strength of mudrocks has deteriorated as it condition changed from dry to short-term inundated and finally to long-term inundated.

Keywords: mudrocks, sedimentary rocks, inundation, shear strength

Procedia PDF Downloads 219
1202 PSS®E Based Modelling, Simulation and Synchronous Interconnection of Eastern Grid and North-Eastern Regional Grid of India

Authors: Toushik Maiti, Saibal Chatterjee, Kamaljyoti Gogoi, Arijit Basuray

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Eastern Regional(ER) Grid and North Eastern Regional (NER) Grid are two major grids of Eastern Part of India. Both of the grid consists of voltage level 765kV, 400 kV, 220 kV and numerous buses at lower voltage range. Eastern Regional Grid and North Eastern Regional Grid are not only connected among themselves but are also connected to various other grids of India. ER and NER Grid having various HVDC lines or back to back systems which form the total network. The studied system comprises of 340 buses of different voltage levels and transmission lines running over a length of 32089 km. The validation of load flow has been done using IEEE STANDARD 30 bus system. The power flow simulation analysis has been performed after synchronizing both the Eastern Grid and North-Eastern Regional Grid of India using Power System Simulators for Engineering (PSS®E) Important inferences has been drawn from the study.

Keywords: HVDC, load flow, PSS®E, unsymmetrical and symmetrical faults

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1201 Damages Inflicted on Steel Structures and Metal Buildings due to Insufficient Supervision and Monitoring and Non-Observance of the Rules of the Regulations

Authors: Ehsan Sadie

Abstract:

Despite the experience of heavy losses and damages of recent earthquakes such as 8 km E of Pāhala, Hawaii, 11 km W of Salvaleón de Higüey, Dominican Republic and 49 km SSE of Punta Cana, Dominican Republic earthquakes, the possibility of large earthquakes in most populated areas of any country and the serious need for quality control in the design and implementation of buildings, not enough attention has been paid to the proper construction. Steel structures constitute a significant part of construction in any metropolitan area. This article gives a brief overview of the implementation status of these buildings in urban areas and considers the weaknesses of performance that typically occur due to negligence or insufficient mastery of the building supervisor in the principles of operation of earthquake-resistant buildings, and provides appropriate and possible solutions to improve the construction.

Keywords: bracing member, concentrated load, diaphragm system, earthquake engineering, load-bearing system, shear force, seismic retrofitting, steel building, strip foundation, supervising engineer, vulnerability of building

Procedia PDF Downloads 114
1200 A Simulative Approach for JIT Parts-Feeding Policies

Authors: Zhou BingHai, Fradet Victor

Abstract:

Lean philosophy follows the simple principle of “creating more value with fewer resources”. In accordance with this policy, material handling can be managed by the mean of Kanban which by triggering every feeding tour only when needed regulates the flow of material in one of the most efficient way. This paper focuses on Kanban Supermarket’s parameters and their optimization on a purely cost-based point of view. Number and size of forklifts, as well as size of the containers they carry, will be variables of the cost function which includes handling costs, inventory costs but also shortage costs. With an innovative computational approach encoded into industrial engineering software Tecnomatix and reproducing real-life conditions, a fictive assembly line is established and produces a random list of orders. Multi-scenarios are then run to study the impact of each change of parameter and the variation of costs it implies. Lastly, best-case scenarios financially speaking are selected.

Keywords: Kanban, supermarket, parts-feeding policies, multi-scenario simulation, assembly line

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1199 Handling Complexity of a Complex System Design: Paradigm, Formalism and Transformations

Authors: Hycham Aboutaleb, Bruno Monsuez

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Current systems' complexity has reached a degree that requires addressing conception and design issues while taking into account environmental, operational, social, legal, and financial aspects. Therefore, one of the main challenges is the way complex systems are specified and designed. The exponentially growing effort, cost, and time investment of complex systems in modeling phase emphasize the need for a paradigm, a framework, and an environment to handle the system model complexity. For that, it is necessary to understand the expectations of the human user of the model and his limits. This paper presents a generic framework for designing complex systems, highlights the requirements a system model needs to fulfill to meet human user expectations, and suggests a graph-based formalism for modeling complex systems. Finally, a set of transformations are defined to handle the model complexity.

Keywords: higraph-based, formalism, system engineering paradigm, modeling requirements, graph-based transformations

Procedia PDF Downloads 387
1198 Mathematical Modeling of Activated Sludge Process: Identification and Optimization of Key Design Parameters

Authors: Ujwal Kishor Zore, Shankar Balajirao Kausley, Aniruddha Bhalchandra Pandit

Abstract:

There are some important design parameters of activated sludge process (ASP) for wastewater treatment and they must be optimally defined to have the optimized plant working. To know them, developing a mathematical model is a way out as it is nearly commensurate the real world works. In this study, a mathematical model was developed for ASP, solved under activated sludge model no 1 (ASM 1) conditions and MATLAB tool was used to solve the mathematical equations. For its real-life validation, the developed model was tested for the inputs from the municipal wastewater treatment plant and the results were quite promising. Additionally, the most cardinal assumptions required to design the treatment plant are discussed in this paper. With the need for computerization and digitalization surging in every aspect of engineering, this mathematical model developed might prove to be a boon to many biological wastewater treatment plants as now they can in no time know the design parameters which are required for a particular type of wastewater treatment.

Keywords: waste water treatment, activated sludge process, mathematical modeling, optimization

Procedia PDF Downloads 128
1197 Influence of Major Axis on the Aerodynamic Characteristics of Elliptical Section

Authors: K. B. Rajasekarababu, J. Karthik, G. Vinayagamurthy

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This paper is intended to explain the influence of major axis on aerodynamic characteristics of elliptical section. Many engineering applications such as off shore structures, bridge piers, civil structures and pipelines can be modelled as a circular cylinder but flow over complex bodies like, submarines, Elliptical wing, fuselage, missiles, and rotor blades, in which the parameters such as axis ratio can influence the flow characteristics of the wake and nature of separation. Influence of Major axis in Flow characteristics of elliptical sections are examined both experimentally and computationally in this study. For this research, four elliptical models with varying major axis [*AR=1, 4, 6, 10] are analysed. Experimental works have been conducted in a subsonic wind tunnel. Furthermore, flow characteristics on elliptical model are predicted from k-ε turbulence model using the commercial CFD packages by pressure based transient solver with Standard wall conditions.The analysis can be extended to estimation and comparison of Drag coefficient and Fatigue analysis of elliptical sections.

Keywords: elliptical section, major axis, aerodynamic characteristics, k-ε turbulence model

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1196 Ceramic Composites and Its Applications for Pb Adsorption

Authors: C. L. Popa, S. L. Iconaru, A. Costescu, C. S. Ciobanu, M. Motelica Heino, R. Guegan, D. Predoi

Abstract:

Surface functionalization of ceramic composites with a special focus on tetraethyl orthosilicate (TEOS) and hydroxyapatite (HAp) is discoursed. Mesoporous ceramic HAp-TEOS composites were prepared by the incorporation of hydroxyapatite into tetraethyl orthosilicate by sol-gel method. The resulting samples were analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, and Raman spectroscopy and nitrogen physisorption. The removal of Pb2+ ions from aqueous solutions was evaluated using Atomic Absorbtion Spectroscopy (AAS). Removal experiments of Pb2+ ions were carried out in aqueous solutions with controlled Pb2+ at pH ~ 3 and pH ~ 5. After removal experiment of Pb2+ at pH 3 and pH 5, porous hydroxyapatite nanoparticles is transformed into PbHAp_3 and PbHAp_5 via the adsorption of Pb2+ ions followed by the cation exchange reaction. The diffraction patterns show that THAp nanoparticles were successfully coated with teos without any structural changes. On the other, the AAS analysis showed that THAp can be useful in the removal Pb2+ from water contaminated.

Keywords: teos, hydroxyapatite, environment applications, biosystems engineering

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1195 A Novel Algorithm for Parsing IFC Models

Authors: Raninder Kaur Dhillon, Mayur Jethwa, Hardeep Singh Rai

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Information technology has made a pivotal progress across disparate disciplines, one of which is AEC (Architecture, Engineering and Construction) industry. CAD is a form of computer-aided building modulation that architects, engineers and contractors use to create and view two- and three-dimensional models. The AEC industry also uses building information modeling (BIM), a newer computerized modeling system that can create four-dimensional models; this software can greatly increase productivity in the AEC industry. BIM models generate open source IFC (Industry Foundation Classes) files which aim for interoperability for exchanging information throughout the project lifecycle among various disciplines. The methods developed in previous studies require either an IFC schema or MVD and software applications, such as an IFC model server or a Building Information Modeling (BIM) authoring tool, to extract a partial or complete IFC instance model. This paper proposes an efficient algorithm for extracting a partial and total model from an Industry Foundation Classes (IFC) instance model without an IFC schema or a complete IFC model view definition (MVD).

Keywords: BIM, CAD, IFC, MVD

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1194 A Critical Look on Clustered Regularly Interspaced Short Palindromic Repeats Method Based on Different Mechanisms

Authors: R. Sulakshana, R. Lakshmi

Abstract:

Clustered Regularly Interspaced Short Palindromic Repeats, CRISPR associate (CRISPR/Cas) is an adaptive immunity system found in bacteria and archaea. It has been modified to serve as a potent gene editing tool. Moreover, it has found widespread use in the field of genome research because of its accessibility and low cost. Several bioinformatics methods have been created to aid in the construction of specific single guide RNA (sgRNA), which is highly active and crucial to CRISPR/Cas performance. Various Cas proteins, including Cas1, Cas2, Cas9, and Cas12, have been used to create genome engineering tools because of their programmable sequence specificity. Class 1 and 2 CRISPR/Cas systems, as well as the processes of all known Cas proteins (including Cas9 and Cas12), are discussed in this review paper. In addition, the various CRISPR methodologies and their tools so far discovered are discussed. Finally, the challenges and issues in the CRISPR system along with future works, are presented.

Keywords: gene editing tool, Cas proteins, CRISPR, guideRNA, programmable sequence

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1193 Investigation of Biofilm Formation in Clinical Strains of Klebsiella pneumoniae and Klebsiella rhinoscleromatis

Authors: Gulcan Sahal, Nermin Hande Avcioglu, Isil Seyis Bilkay

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Klebsiella species which are natural colonizers of human upper respiratory and human gastrointestinal tracts are also responsible for every reoccurring nosocomial infections by means of having ability to form slimy layers known as biofilm on many surfaces. Therefore, in this study, investigation of biofilm formation in K. pneumoniae and K. rhinoscleromatis and examination of each Klebsiella strains’ clinical information in the light of their biofilm formation results were aimed. In this respect, biofilm formation of Klebsiella strains was analyzed via crystal violet binding assay. According to our results, biofilm formation levels of K. pneumoniae and K. rhinoscleromatis strains were different from each other. Additionally, in comparison to K. rhinoscleromatis strains, K. pneumoniae was observed to include higher amounts of strong biofilm forming strains. Besides, it was also seen that clinical information of patients from which strong biofilm forming Klebsiella strains were isolated were similar to each other. Our results indicate that there should be more precautions against K. pneumoniae which includes higher amount of strong biofilm forming strains.

Keywords: biofilm formation, Klebsiella pneumoniae, Klebsiella rhinoscleromatis, biosystems engineering

Procedia PDF Downloads 376
1192 Design and Simulation of Step Structure RF MEMS Switch for K Band Applications

Authors: G. K. S. Prakash, Rao K. Srinivasa

Abstract:

MEMS plays an important role in wide range of applications like biological, automobiles, military and communication engineering. This paper mainly investigates on capacitive shunt RF MEMS switch with low actuation voltage and low insertion losses. To trim the pull-in voltage, a step structure has introduced to trim air gap between the beam and the dielectric layer with that pull in voltage is trim to 2.9 V. The switching time of the proposed switch is 39.1μs, and capacitance ratio is 67. To get more isolation, we have used aluminum nitride as dielectric material instead of silicon nitride (Si₃N₄) and silicon dioxide (SiO₂) because aluminum nitride has high dielectric constant (εᵣ = 9.5) increases the OFF capacitance and eventually increases the isolation of the switch. The results show that the switch is ON state involves return loss (S₁₁) less than -25 dB up to 40 GHz and insertion loss (S₂₁) is more than -1 dB up to 35 GHz. In OFF state switch shows maximum isolation (S₂₁) of -38 dB occurs at a frequency of 25-27 GHz for K band applications.

Keywords: RF MEMS, actuation voltage, isolation loss, switches

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1191 Mathematical Knowledge a Prerequisite for Science Education Courses in Tertiary Institution

Authors: Esther Yemisi Akinjiola

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Mathematics has been regarded as the backbone of science and technological development, without which no nation can achieve any sustainable growth and development. Mathematics is a useful tool to simplify science by quantification of phenomena; hence physics and chemistry cannot be done without Calculus and Statistics. Mathematics is used in physical science to calculate the measurement of objects and their characteristics, as well as to show the relationship between different functions and properties. Mathematics is the building block for everything in our daily lives, including the use of mobile devices, architecture design, ancient arts, engineering sports, and. among others. Therefore the study of Mathematics is made compulsory at primary, basic, and secondary school levels. Thus, this paper discusses the concepts of Mathematics, science, and their relationships. Also, it discusses Mathematics contents needed to study science-oriented courses such as physics education, chemistry education, and biology education in the tertiary institution. The paper concluded that without adequate knowledge of Mathematics, it will be difficult, if not impossible, for science education students to cope in their field of study.

Keywords: mathematical knowledge, prerequisite, science education, tertiary institution

Procedia PDF Downloads 71
1190 Digital Geomatics Trends for Production and Updating Topographic Map by Using Digital Generalization Procedures

Authors: O. Z. Jasim

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An accuracy digital map must satisfy the users for two main requirements, first, map must be visually readable and second, all the map elements must be in a good representation. These two requirements hold especially true for map generalization which aims at simplifying the representation of cartographic data. Different scales of maps are very important for any decision in any maps with different scales such as master plan and all the infrastructures maps in civil engineering. Cartographer cannot project the data onto a piece of paper, but he has to worry about its readability. The map layout of any geodatabase is very important, this layout is help to read, analyze or extract information from the map. There are many principles and guidelines of generalization that can be find in the cartographic literature. A manual reduction method for generalization depends on experience of map maker and therefore produces incompatible results. Digital generalization, rooted from conventional cartography, has become an increasing concern in both Geographic Information System (GIS) and mapping fields. This project is intended to review the state of the art of the new technology and help to understand the needs and plans for the implementation of digital generalization capability as well as increase the knowledge of production topographic maps.

Keywords: cartography, digital generalization, mapping, GIS

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1189 Meteorological Effect on Exergetic and Exergoeconomics Parameters of a Wind Turbine

Authors: Muhammad Abid

Abstract:

In this study, we performed the comparative exergetic and exergoeconomic analyses of a wind turbine over a period of twelve months from 1st January to 30th December 2011. The turbine is part of a wind-PV hybrid system with hydrogen storage, located on the roof of Mechanical Engineering Department, King Saud University, Riyadh, Saudi Arabia. The rated power output from this turbine is 1.7 W with a rated wind speed of 12 m/s and cut-in/cut-out wind speeds of 3/14 m/s. We utilize a wide range of experimental data in the analysis and assessment. We determine exergy efficiencies and their relation with meteorological variables, such as temperature and density. We also calculate exergoeconomic parameter R ̇_ex and its dependence on the temperature, using the average values for twelve months of the year considered for comparison purposes. The exergy efficiency changes from 0.12 to 0.31 while the density varies between 1.31 and 1.2 kg/m3 for different temperature values. The R ̇_ex has minimum and maximum values of 0.02 and 0.81, respectively, while the temperature is in the range of 8-24°C for various wind velocity values.

Keywords: exergy, efficiency, renewable energy, wind energy, meteorological variables

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1188 Concentration of Droplets in a Transient Gas Flow

Authors: Timur S. Zaripov, Artur K. Gilfanov, Sergei S. Sazhin, Steven M. Begg, Morgan R. Heikal

Abstract:

The calculation of the concentration of inertial droplets in complex flows is encountered in the modelling of numerous engineering and environmental phenomena; for example, fuel droplets in internal combustion engines and airborne pollutant particles. The results of recent research, focused on the development of methods for calculating concentration and their implementation in the commercial CFD code, ANSYS Fluent, is presented here. The study is motivated by the investigation of the mixture preparation processes in internal combustion engines with direct injection of fuel sprays. Two methods are used in our analysis; the Fully Lagrangian method (also known as the Osiptsov method) and the Eulerian approach. The Osiptsov method predicts droplet concentrations along path lines by solving the equations for the components of the Jacobian of the Eulerian-Lagrangian transformation. This method significantly decreases the computational requirements as it does not require counting of large numbers of tracked droplets as in the case of the conventional Lagrangian approach. In the Eulerian approach the average droplet velocity is expressed as a function of the carrier phase velocity as an expansion over the droplet response time and transport equation can be solved in the Eulerian form. The advantage of the method is that droplet velocity can be found without solving additional partial differential equations for the droplet velocity field. The predictions from the two approaches were compared in the analysis of the problem of a dilute gas-droplet flow around an infinitely long, circular cylinder. The concentrations of inertial droplets, with Stokes numbers of 0.05, 0.1, 0.2, in steady-state and transient laminar flow conditions, were determined at various Reynolds numbers. In the steady-state case, flows with Reynolds numbers of 1, 10, and 100 were investigated. It has been shown that the results predicted using both methods are almost identical at small Reynolds and Stokes numbers. For larger values of these numbers (Stokes — 0.1, 0.2; Reynolds — 10, 100) the Eulerian approach predicted a wider spread in concentration in the perturbations caused by the cylinder that can be attributed to the averaged droplet velocity field. The transient droplet flow case was investigated for a Reynolds number of 200. Both methods predicted a high droplet concentration in the zones of high strain rate and low concentrations in zones of high vorticity. The maxima of droplet concentration predicted by the Osiptsov method was up to two orders of magnitude greater than that predicted by the Eulerian method; a significant variation for an approach widely used in engineering applications. Based on the results of these comparisons, the Osiptsov method has resulted in a more precise description of the local properties of the inertial droplet flow. The method has been applied to the analysis of the results of experimental observations of a liquid gasoline spray at representative fuel injection pressure conditions. The preliminary results show good qualitative agreement between the predictions of the model and experimental data.

Keywords: internal combustion engines, Eulerian approach, fully Lagrangian approach, gasoline fuel sprays, droplets and particle concentrations

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1187 Time Series Analysis of Radon Concentration at Different Depths in an Underground Goldmine

Authors: Theophilus Adjirackor, Frederic Sam, Irene Opoku-Ntim, David Okoh Kpeglo, Prince K. Gyekye, Frank K. Quashie, Kofi Ofori

Abstract:

Indoor radon concentrations were collected monthly over a period of one year in 10 different levels in an underground goldmine, and the data was analyzed using a four-moving average time series to determine the relationship between the depths of the underground mine and the indoor radon concentration. The detectors were installed in batches within four quarters. The measurements were carried out using LR115 solid-state nuclear track detectors. Statistical models are applied in the prediction and analysis of the radon concentration at various depths. The time series model predicted a positive relationship between the depth of the underground mine and the indoor radon concentration. Thus, elevated radon concentrations are expected at deeper levels of the underground mine, but the relationship was insignificant at the 5% level of significance with a negative adjusted R2 (R2 = – 0.021) due to an appropriate engineering and adequate ventilation rate in the underground mine.

Keywords: LR115, radon concentration, rime series, underground goldmine

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1186 Effect of CuO, Al₂O₃ and ZnO Nanoparticles on the Response Time for Natural Convection

Authors: Mefteh Bouhalleb

Abstract:

With the recent progress in nanotechnology, nanofluids have excellent potentiality in many modern engineering processes, particularly for solar systems such as concentrated solar power plants (CSP). In this context, a numerical simulation is performed to investigate laminar natural convection nanofluids in an inclined rectangular enclosure. Mass conservation, momentum, and energy equations are numerically solved by the finite volume element method using the SIMPLER algorithm for pressure-velocity coupling. In this work, we tested the acting factors on the system response time, such as the particle volume fraction of nanoparticles, particle material, particle size, an inclination angle of enclosure and Rayleigh number. The results show that the diameter of solid particles and Rayleigh number plays an important role in the system response time. The orientation angle of the cavity affects the system response time. A phenomenon of hysteresis appears when the system does not return to its initial state.

Keywords: nanofluid, nanoparticles, heat transfer, time response

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1185 Effect of Zirconium Addition to Aluminum Grain Refined by Ti on its Resistance to Wear: A Three-Dimensional Approach

Authors: S. M. A. Al-Qawabah, A. I. O. Zaid

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Aluminum and its alloys are versatile materials which are widely used in industrial and engineering applications due to their good and useful properties e.g. high strength to weight ratio, high thermal and electrical conductivities and good resistance to corrosion. However, against these favorable properties they have the disadvantage they solidifying large grain columnar structure which negatively affects their mechanical properties and surface quality. Aluminum alloys are normally grain refined by some alloying elements, such as Ti, Ti-B or Zr. In this paper, the effect of zirconium addition to Al grain refined by Ti after extrusion on its wear resistance is investigated under different loads and sliding speeds namely at 5,10 and 20 N loads and sliding speeds ranging from m/min. and m/min. the results are presented in three-dimensional wear mode. To the best the authors' knowledge, the wear of aluminum in 3-dimensions has never been tackled before. In this work, the wear resistance of by presenting the results of wear are presented and discussed on the time, load and speed plots.

Keywords: aluminum grain refined, addition of titanium, wear resistance, titanium

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1184 Chaotic Search Optimal Design and Modeling of Permanent Magnet Synchronous Linear Motor

Authors: Yang Yi-Fei, Luo Min-Zhou, Zhang Fu-Chun, He Nai-Bao, Xing Shao-Bang

Abstract:

This paper presents an electromagnetic finite element model of permanent magnet synchronous linear motor and distortion rate of the air gap flux density waveform is analyzed in detail. By designing the sample space of the parameters, nonlinear regression modeling of the orthogonal experimental design is introduced. We put forward for possible air gap flux density waveform sine electromagnetic scheme. Parameters optimization of the permanent magnet synchronous linear motor is also introduced which is based on chaotic search and adaptation function. Simulation results prove that the pole shifting does not affect the motor back electromotive symmetry based on the structural parameters, it provides a novel way for the optimum design of permanent magnet synchronous linear motor and other engineering.

Keywords: permanent magnet synchronous linear motor, finite element analysis, chaotic search, optimization design

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1183 The Evaluation of Electricity Generation and Consumption from Solar Generator: A Case Study at Rajabhat Suan Sunandha’s Learning Center in Samutsongkram

Authors: Chonmapat Torasa

Abstract:

This paper presents the performance of electricity generation and consumption from solar generator installed at Rajabhat Suan Sunandha’s learning center in Samutsongkram. The result from the experiment showed that solar cell began to work and distribute the current into the system when the solar energy intensity was 340 w/m2, starting from 8:00 am to 4:00 pm (duration of 8 hours). The highest intensity read during the experiment was 1,051.64w/m2. The solar power was 38.74kWh/day. The electromotive force from solar cell averagely was 93.6V. However, when connecting solar cell with the battery charge controller system, the voltage was dropped to 69.07V. After evaluating the power distribution ability and electricity load of tested solar cell, the result showed that it could generate power to 11 units of 36-wattfluorescent lamp bulbs, which was altogether 396W. In the meantime, the AC to DC power converter generated 3.55A to the load, and gave 781VA.

Keywords: solar cell, solar-cell power generating system, computer, systems engineering

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1182 Using Greywolf Optimized Machine Learning Algorithms to Improve Accuracy for Predicting Hospital Readmission for Diabetes

Authors: Vincent Liu

Abstract:

Machine learning algorithms (ML) can achieve high accuracy in predicting outcomes compared to classical models. Metaheuristic, nature-inspired algorithms can enhance traditional ML algorithms by optimizing them such as by performing feature selection. We compare ten ML algorithms to predict 30-day hospital readmission rates for diabetes patients in the US using a dataset from UCI Machine Learning Repository with feature selection performed by Greywolf nature-inspired algorithm. The baseline accuracy for the initial random forest model was 65%. After performing feature engineering, SMOTE for class balancing, and Greywolf optimization, the machine learning algorithms showed better metrics, including F1 scores, accuracy, and confusion matrix with improvements ranging in 10%-30%, and a best model of XGBoost with an accuracy of 95%. Applying machine learning this way can improve patient outcomes as unnecessary rehospitalizations can be prevented by focusing on patients that are at a higher risk of readmission.

Keywords: diabetes, machine learning, 30-day readmission, metaheuristic

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1181 Risk Assessment Results in Biogas Production from Agriculture Biomass

Authors: Sandija Zeverte-Rivza, Irina Pilvere, Baiba Rivza

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The use of renewable energy sources incl. biogas has become topical in accordance with the increasing demand for energy, decrease of fossil energy resources and the efforts to reduce greenhouse gas emissions as well as to increase energy independence from the territories where fossil energy resources are available. As the technologies of biogas production from agricultural biomass develop, risk assessment and risk management become necessary for farms producing such a renewable energy. The need for risk assessments has become particularly topical when discussions on changing the biogas policy in the EU take place, which may influence the development of the sector in the future, as well as the operation of existing biogas facilities and their income level. The current article describes results of the risk assessment for farms producing biomass from agriculture biomass in Latvia, the risk assessment system included 24 risks, that affect the whole biogas production process and the obtained results showed the high significance of political and production risks.

Keywords: biogas production, risks, risk assessment, biosystems engineering

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1180 Physico-Mechanical Behavior of Indian Oil Shales

Authors: K. S. Rao, Ankesh Kumar

Abstract:

The search for alternative energy sources to petroleum has increased these days because of increase in need and depletion of petroleum reserves. Therefore the importance of oil shales as an economically viable substitute has increased many folds in last 20 years. The technologies like hydro-fracturing have opened the field of oil extraction from these unconventional rocks. Oil shale is a compact laminated rock of sedimentary origin containing organic matter known as kerogen which yields oil when distilled. Oil shales are formed from the contemporaneous deposition of fine grained mineral debris and organic degradation products derived from the breakdown of biota. Conditions required for the formation of oil shales include abundant organic productivity, early development of anaerobic conditions, and a lack of destructive organisms. These rocks are not gown through the high temperature and high pressure conditions in Mother Nature. The most common approach for oil extraction is drastically breaking the bond of the organics which involves retorting process. The two approaches for retorting are surface retorting and in-situ processing. The most environmental friendly approach for extraction is In-situ processing. The three steps involved in this process are fracturing, injection to achieve communication, and fluid migration at the underground location. Upon heating (retorting) oil shale at temperatures in the range of 300 to 400°C, the kerogen decomposes into oil, gas and residual carbon in a process referred to as pyrolysis. Therefore it is very important to understand the physico-mechenical behavior of such rocks, to improve the technology for in-situ extraction. It is clear from the past research and the physical observations that these rocks will behave as an anisotropic rock so it is very important to understand the mechanical behavior under high pressure at different orientation angles for the economical use of these resources. By knowing the engineering behavior under above conditions will allow us to simulate the deep ground retorting conditions numerically and experimentally. Many researchers have investigate the effect of organic content on the engineering behavior of oil shale but the coupled effect of organic and inorganic matrix is yet to be analyzed. The favourable characteristics of Assam coal for conversion to liquid fuels have been known for a long time. Studies have indicated that these coals and carbonaceous shale constitute the principal source rocks that have generated the hydrocarbons produced from the region. Rock cores of the representative samples are collected by performing on site drilling, as coring in laboratory is very difficult due to its highly anisotropic nature. Different tests are performed to understand the petrology of these samples, further the chemical analyses are also done to exactly quantify the organic content in these rocks. The mechanical properties of these rocks are investigated by considering different anisotropic angles. Now the results obtained from petrology and chemical analysis are correlated with the mechanical properties. These properties and correlations will further help in increasing the producibility of these rocks. It is well established that the organic content is negatively correlated to tensile strength, compressive strength and modulus of elasticity.

Keywords: oil shale, producibility, hydro-fracturing, kerogen, petrology, mechanical behavior

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1179 Surface Nanocrystalline and Hardening Effects of Ti–Al–V Alloy by Electropulsing Ultrasonic Shock

Authors: Xiaoxin Ye, Guoyi Tang

Abstract:

The effect of electropulsing ultrasonic shock (EUS) on the surface hardening and microstructure of Ti6Al4V alloy was studied. It was found that electropulsing improved the microhardness dramatically both in the influential depth and maximum value, compared with the only ultrasonic-shocked sample. It’s indicated that refined surface layer with nanocrystalline and improved microhardness were obtained on account of surface severe plastic deformation, dynamic recrystallization (DRX) and phase change, which was implemented at relative low temperature and high strain rate/capacity due to the coupling of the thermal and athermal effects of EUS. It’s different from conventional experiments and theory. It’s discussed that the positive contributions of EPT in the thermodynamics and kinetics of microstructure and properties change were attributed to the reduction of nucleation energy barrier and acceleration of atomic diffusion. Therefore, it’s supposed that EUS is an energy-saving and high-efficiency method of surface treatment technique with the help of high-energy electropulses, which is promising in cost reduction of the surface engineering and energy management.

Keywords: titanium alloys, electropulsing, ultrasonic shock, microhardness, nanocrystalline

Procedia PDF Downloads 273
1178 Knowledge Representation and Inconsistency Reasoning of Class Diagram Maintenance in Big Data

Authors: Chi-Lun Liu

Abstract:

Requirements modeling and analysis are important in successful information systems' maintenance. Unified Modeling Language (UML) class diagrams are useful standards for modeling information systems. To our best knowledge, there is a lack of a systems development methodology described by the organism metaphor. The core concept of this metaphor is adaptation. Using the knowledge representation and reasoning approach and ontologies to adopt new requirements are emergent in recent years. This paper proposes an organic methodology which is based on constructivism theory. This methodology is a knowledge representation and reasoning approach to analyze new requirements in the class diagrams maintenance. The process and rules in the proposed methodology automatically analyze inconsistencies in the class diagram. In the big data era, developing an automatic tool based on the proposed methodology to analyze large amounts of class diagram data is an important research topic in the future.

Keywords: knowledge representation, reasoning, ontology, class diagram, software engineering

Procedia PDF Downloads 217