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Optimization

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Full-Text Articles in Engineering

Probe-Pulse Optimization For Nonresonant Suppression In Hybrid Fs/Ps Coherent Anti-Stokes Raman Scattering At High Temperature, Joseph D. Miller, Mikhail N. Slipchenko, Terrence R. Meyer Nov 2015

Probe-Pulse Optimization For Nonresonant Suppression In Hybrid Fs/Ps Coherent Anti-Stokes Raman Scattering At High Temperature, Joseph D. Miller, Mikhail N. Slipchenko, Terrence R. Meyer

Terrence R Meyer

Hybrid femtosecond/picosecond coherent anti-Stokes Raman scattering (fs/ps CARS) offers accurate thermometry at kHz rates for combustion diagnostics. In high-temperature flames, selection of probe-pulse characteristics is key to simultaneously optimizing signal-to-nonresonant-background ratio, signal strength, and spectral resolution. We demonstrate a simple method for enhancing signal-to-nonresonant-background ratio by using a narrowband Lorentzian filter to generate a time-asymmetric probe pulse with full-width-half-maximum (FWHM) pulse width of only 240 fs. This allows detection within just 310 fs after the Raman excitation for eliminating nonresonant background while retaining 45% of the resonant signal at 2000 K. The narrow linewidth is comparable to that of a …


Stochastic Modeling And Optimization Of Multi-Plant Capacity Planning Problem, Anoop Verma, Nagesh Shukla, S.K Tyagi, Nishikant Mishra Sep 2015

Stochastic Modeling And Optimization Of Multi-Plant Capacity Planning Problem, Anoop Verma, Nagesh Shukla, S.K Tyagi, Nishikant Mishra

Nagesh Shukla

n this paper the problem of capacity planning under risk from demand and price/cost uncertainty of the finished products is addressed. The deterministic model is extended into a two-stage stochastic model with fixed recourse by means of various expected levels of demand as random. A recourse penalty is also included in the objective for both shortage and surplus in the finished products. The model is analyzed to quantify the risk using Markowitz mean-variance model.


Particle Swarm Optimization Approach For Maximizing The Yield Of A Coal Preparation Plant, Vishal Gupta, Hussain Unjawala, Ajay Mohan Mahajan, Manoj Mohanty Apr 2015

Particle Swarm Optimization Approach For Maximizing The Yield Of A Coal Preparation Plant, Vishal Gupta, Hussain Unjawala, Ajay Mohan Mahajan, Manoj Mohanty

Dr. Ajay Mahajan

This paper presents the use of particle swarm optimization to maximize the clean coal yield of a coal preparation plant that typically has multiple cleaning circuits that produce the same product quality so that the blend of clean coal meets the targeted product quality contraints. Particle swarm is used for the yield optimization while satisfying multiple product quality restraints. The results show a 2.73% increase in the yield can be achieved leading to additional revenue of $5,460,000 per annum for a plant producing 10 million tons of clean coal per year without significantly adding to the implementation/operation cost.


Multiple-Objective Optimization In Precision Laser Cutting Of Different Thermoplastics Apr 2015

Multiple-Objective Optimization In Precision Laser Cutting Of Different Thermoplastics

Faculty of Engineering University of Malaya

Thermoplastics are increasingly being used in biomedical, automotive and electronics industries due to their excellent physical and chemical properties. Due to the localized and non-contact process, use of lasers for cutting could result in precise cut with small heat-affected zone (HAZ). Precision laser cutting involving various materials is important in high-volume manufacturing processes to minimize operational cost, error reduction and improve product quality. This study uses grey relational analysis to determine a single optimized set of cutting parameters for three different thermoplastics. The set of the optimized processing parameters is determined based on the highest relational grade and was found …


A Generalized Energy-Based Kinetic Model For Microwave-Assisted Extraction Of Bioactive Compounds From Plants Mar 2015

A Generalized Energy-Based Kinetic Model For Microwave-Assisted Extraction Of Bioactive Compounds From Plants

Faculty of Engineering University of Malaya

By considering the absorbed power and energy based on heating power profile during extraction, a generalized model with washing coefficient (b), diffusion coefficient (k) and predictive parameter namely absorbed power density (APD) was developed for microwave-assisted extraction (MAE) at any operational heating modes. To study the model, MAE of flavonoids from cocoa (Theobroma cacao L.) leaves was conducted using the heating modes (constant-power, two-steps-power, intermittent-power and constant-temperature) at various microwave power (100-300W) and extraction temperature (50 degrees C and 70 degrees C). The results shows that the model (b = 0.5595 and k' = 0.01279 mL/J) is able to predict …


Stiffness Modulus Of Polyethylene Terephthalate Modified Asphalt Mixture: A Statistical Analysis Of The Laboratory Testing Results Mar 2015

Stiffness Modulus Of Polyethylene Terephthalate Modified Asphalt Mixture: A Statistical Analysis Of The Laboratory Testing Results

Faculty of Engineering University of Malaya

Stiffness of asphalt mixture is a fundamental design parameter of flexible pavement. According to literature, stiffness value is very susceptible to environmental and loading conditions. In this paper, effects of applied stress and temperature on the stiffness modulus of unmodified and Polyethylene Terephthalate (PET) modified asphalt mixtures were evaluated using Response Surface Methodology (RSM). A quadratic model was successfully fitted to the experimental data. Based on the results achieved in this study, the temperature variation had the highest impact on the mixture's stiffness. Besides, PET content and amount of stress showed to have almost the same effect on the stiffness …


Dimensional Synthesis Of Four Bar Mechanism Using Genetic Algorithm, Innovative Research Publications Irp India, S. S. Shete, S. A. Kulkarni Mar 2015

Dimensional Synthesis Of Four Bar Mechanism Using Genetic Algorithm, Innovative Research Publications Irp India, S. S. Shete, S. A. Kulkarni

Innovative Research Publications IRP India

The dimensional synthesis is done by using Genetic Algorithm to achieve a desired trajectory. Three problems are analyzed having different curvature. The program is authored in MATLAB® 2010a. The error is seen to be in the permissible prescribed limit. The prototyping of straight line trajectory analysis is also done in ADAMS®


Research On Optimization Of Plunge Centerless Grinding Process Using Genetic Algorithm And Response Surface Method, Innovative Research Publications Irp India, Phan Bui Khoi, Do Duc Trung, Ngo Cuong, Nguyen Dinh Man Mar 2015

Research On Optimization Of Plunge Centerless Grinding Process Using Genetic Algorithm And Response Surface Method, Innovative Research Publications Irp India, Phan Bui Khoi, Do Duc Trung, Ngo Cuong, Nguyen Dinh Man

Innovative Research Publications IRP India

This paper presents the research on optimization of plunge centerless grinding process when grind 20X – carbon infiltration steel (ГOCT standard - Russia) to achieve minimum of roundness error value. The input parameters are center height angle of the workpiece (  ), longitudinal grinding wheel dressing feed-rate ( Ssd ), plunge feed-rate ( k S ) and control wheel velocity ( dd v ). Using the result of 29 runs in Central Composite Design matrix to given the second order roundness error model. Genetic algorithm and Response surface method were used to focus on determination of optimum centerless grinding …


Electrospinning Of Polymethyl Methacrylate Nanofibers: Optimization Of Processing Parameters Using The Taguchi Design Of Experiments Mar 2015

Electrospinning Of Polymethyl Methacrylate Nanofibers: Optimization Of Processing Parameters Using The Taguchi Design Of Experiments

Faculty of Engineering University of Malaya

The effects of polymer concentration and electrospinning parameters on the diameter of electrospun polymethyl methacrylate (PMMA) fibers were experimentally investigated. It was also studied how the controlled factors would affect the output with the intention of finding the optimal electrospinning settings in order to obtain the smallest PMMA fiber diameter. Subsequently the solution feed rate, needle gauge diameter, supply voltage, polymer concentration and tip-to-collector distance were considered as the control factors. To achieve these aims, Taguchi's mixed-level parameter design (L-18) was employed for the experimental design. Optimal electrospinning conditions were determined using the signal-to-noise (S/N) ratio that was calculated from …


A Comparative Study Of Multi-Objective Optimal Power Flow Based On Particle Swarm, Evolutionary Programming, And Genetic Algorithm Mar 2015

A Comparative Study Of Multi-Objective Optimal Power Flow Based On Particle Swarm, Evolutionary Programming, And Genetic Algorithm

Faculty of Engineering University of Malaya

This paper compares the performance of three population-based algorithms including particle swarm optimization (PSO), evolutionary programming (EP), and genetic algorithm (GA) to solve the multi-objective optimal power flow (OPF) problem. The unattractive characteristics of the cost-based OPF including loss, voltage profile, and emission justifies the necessity of multi-objective OPF study. This study presents the programming results of the nine essential single-objective and multi-objective functions of OPF problem. The considered objective functions include cost, active power loss, voltage stability index, and emission. The multi-objective optimizations include cost and active power loss, cost and voltage stability index, active power loss and voltage …


Optimizing The Robot Arm Movement Time Using Virtual Reality Robotic Teaching System Feb 2015

Optimizing The Robot Arm Movement Time Using Virtual Reality Robotic Teaching System

Faculty of Engineering University of Malaya

Robots play an important role in performing operations such as welding, drilling and screwing parts in manufacturing. Optimizing the robot arm movement time between different points is an important task which will minimize the make-span and maximize the production rate. But robot programming is a complex task whereby the user needs to teach and control the robot in order to perform a desired action. In order to address the above problem, an integrated 3-dimensional (3D) simulation software and virtual reality (VR) system is developed to simplify and speed up tasks and therefore enhance the quality of manufacturing processes. This system …


Stiffness Performance Of Polyethylene Terephthalate Modified Asphalt Mixtures Estimation Using Support Vector Machine-Firefly Algorithm Feb 2015

Stiffness Performance Of Polyethylene Terephthalate Modified Asphalt Mixtures Estimation Using Support Vector Machine-Firefly Algorithm

Faculty of Engineering University of Malaya

Predicting asphalt pavement performance is an important matter which can save cost and energy. To ensure an accurate estimation of performance of the mixtures, new soft computing techniques can be used. In this study, in order to estimate the stiffness property of Polyethylene Terephthalate (PET) modified asphalt mixture, different soft computing methods were developed, namely: support vector machine-firefly algorithm (SVM-FFA), genetic programming (GP), artificial neural network (ANN) and support vector machine. The support vector machine-firefly algorithm (SVM-FFA) is a metaheuristic search algorithm developed according to the socially dashing manners of fireflies in nature. To develop the models, experiments were performed. …


A New Low-Profile Inverted A-Shaped Patch Antenna For Multi-Band Operations Feb 2015

A New Low-Profile Inverted A-Shaped Patch Antenna For Multi-Band Operations

Faculty of Engineering University of Malaya

This paper presents the design and analysis of a compact modified inverted-A shape multi-band patch antenna for WiMAX and C-band telecommunication satellite applications. The proposed antenna has simple geometrical structure which consist of 20 mm x 20 mm radiating patch with slot loading and fed by 4 mm long microstrip line. The proposed antenna is designed and analyzed by using commercially available full-wave 3D high frequency electromagnetic simulator namely Ansys HFSS. The optimized design of the proposed multi-band patch antenna is fabricated on 1.6 mm thick fiberglass polymer resin dielectric material substrate with reduced ground plane by using in-house PCB …


Effective Utilization Of Excess Energy In Standalone Hybrid Renewable Energy Systems For Improving Comfort Ability And Reducing Cost Of Energy: A Review And Analysis Feb 2015

Effective Utilization Of Excess Energy In Standalone Hybrid Renewable Energy Systems For Improving Comfort Ability And Reducing Cost Of Energy: A Review And Analysis

Faculty of Engineering University of Malaya

One of the features that characterize renewable energy sources is their variability and intermittency. Intermittency covers both the predictable and unpredictable variations of their power outputs and uncertainty in the power availability. To overcome the drawback of intermittency, special design considerations should be taken into account. These additional design considerations increases the overall cost of the renewable energy systems. Adding storage system and/or backup source to the renewable sources is one of the measures used to guarantee the continuity of power supply to the loads, and therefore improve the reliability of the renewable energy systems. The operation of renewable energy …


Fuzzy Logic Based Model For Predicting Surface Roughness Of Machined Al-Si-Cu-Fe Die Casting Alloy Using Different Additives-Turning Jan 2015

Fuzzy Logic Based Model For Predicting Surface Roughness Of Machined Al-Si-Cu-Fe Die Casting Alloy Using Different Additives-Turning

Faculty of Engineering University of Malaya

This paper presents a fuzzy logic artificial intelligence technique for predicting the machining performance of Al-Si-Cu-Fe die casting alloy treated with different additives including strontium, bismuth and antimony to improve surface roughness. The Pareto-ANOVA optimization method was used to obtain the optimum parameter conditions for the machining process. Experiments were carried out using oblique dry CNC turning. The machining parameters of cutting speed, feed rate and depth of cut were optimized according to surface roughness values. The results indicated that a cutting speed of 250 m/min, a feed rate of 0.05 mm/rev, and a depth of cut of 0.15 mm …


Reactive Distillation: A Review Of Optimal Design Using Deterministic And Stochastic Techniques, Juan Gabriel Segovia-Hernández, Salvador Hernández, Adrian Bonilla-Petriciolet Jan 2015

Reactive Distillation: A Review Of Optimal Design Using Deterministic And Stochastic Techniques, Juan Gabriel Segovia-Hernández, Salvador Hernández, Adrian Bonilla-Petriciolet

Adrian Bonilla-Petriciolet

In the last years, the industries have shown interest in the development of reactive separation processes. Reactive distillation can be considered as reaction and distillation combined into one new unit operation and this integrated separation process is a good example of process intensification. This intensified process offers several important advantages that include the increment of the reaction yield and selectivity, the overcoming of thermodynamic restrictions and the considerable reduction in energy, water and solvent consumptions. Therefore, this process configuration has been applied in several chemical industries. However, due to the strong interactions of chemical reactions and heat and mass transfer, …


Effect Of Alcohol-Gasoline Blends Optimization On Fuel Properties, Performance And Emissions Of A Si Engine Jan 2015

Effect Of Alcohol-Gasoline Blends Optimization On Fuel Properties, Performance And Emissions Of A Si Engine

Faculty of Engineering University of Malaya

This study, as an observation, put its utmost effort to emphasize on the development of various physicochemical properties using multiple alcohols (C-2 to C-6) at different ratios compared to that of the conventional ethanol gasoline blend. To optimize the properties of multiple alcohol-gasoline blends, properties of each fuel were measured first. An optimization tool of Microsoft Excel "Solver" was used for obtaining the optimum blend. Using optimizing tool, three optimum blend ratios were selected which possessed maximum heating value (MaxH), maximum research octane number (MaxR) and maximum petroleum displacement (MaxD). These blends were used for testing in a four cylinder …


Optimizing Cutting Parameters In Inclined End Milling For Minimum Surface Residual Stress - Taguchi Approach Jan 2015

Optimizing Cutting Parameters In Inclined End Milling For Minimum Surface Residual Stress - Taguchi Approach

Faculty of Engineering University of Malaya

End milling is an important and common machining operation because of its versatility and capability to produce various profiles and curved surfaces. Inclined end milling possesses the capability to translate in all 3 axes but can perform the cutting operation in only 2 of the 3 axes at a time. This research work focuses on investigating the effect of machined surface inclination angle, axial depth of cut, spindle speed and feed rate for better surface integrity in inclined end milling process utilizing titanium coated carbide ball end mill. An optimization method known as Taguchi optimization was used in order to …


Review Of Improvements In Wire Electrode Properties For Longer Working Time And Utilization In Wire Edm Machining Jan 2015

Review Of Improvements In Wire Electrode Properties For Longer Working Time And Utilization In Wire Edm Machining

Faculty of Engineering University of Malaya

Wire electrical discharge machining (WEDM) is an important technology, which demands high-speed cutting and high-precision machining to realize productivity and improved accuracy for manufacturing hard materials. WEDM has experienced explosive growth and complexity of equipment as well as rising demand for the basic process tool (the wire electrode). Greater taper angles, thicker workpieces, automatic wire threading, and long periods of unattended operation make the selection of the ideal wire a much more critical basis for achieving successful operation. This paper focuses on the evolution of EDM wire electrode technologies from using copper to the widely employed brass wire electrodes and …


Investigating The Electrical Discharge Machining (Edm) Parameter Effects On Al-Mg2si Metal Matrix Composite (Mmc) For High Material Removal Rate (Mrr) And Less Ewr-Rsm Approach Jan 2015

Investigating The Electrical Discharge Machining (Edm) Parameter Effects On Al-Mg2si Metal Matrix Composite (Mmc) For High Material Removal Rate (Mrr) And Less Ewr-Rsm Approach

Faculty of Engineering University of Malaya

Al-Mg2Si composite is a new group of metalmatrix composites (MMCs). Electrical discharge machining (EDM) is a nonconventional machining process for machining electrically conductive materials regardless of hardness, strength and temperature resistance, complex shapes, fine surface finish/textures and accurate dimensions. A copper electrode and oil-based dielectric fluid mixed with aluminum powder were used. The polarity of electrode was positive. Response surface methodology (RSM) was used to analyze EDM of this composite material. This research illustrates the effect of input variables (voltage, current, pulse ON time, and duty factor) on material removal rate (MRR), electrode wear ratio (EWR), and microstructure changes. The …


Estimation Of The Effect Of Catalyst Physical Characteristics On Fenton-Like Oxidation Efficiency Using Adaptive Neuro-Fuzzy Computing Technique Dec 2014

Estimation Of The Effect Of Catalyst Physical Characteristics On Fenton-Like Oxidation Efficiency Using Adaptive Neuro-Fuzzy Computing Technique

Faculty of Engineering University of Malaya

Catalyst size, which determines surface area, is one of the major factors in catalytic performance. In this study, response surface methodology (RSM) and an adaptive neuro-fuzzy inference system (ANFIS) were applied to quantify the effects of physical characteristics of magnetite on Fenton-like oxidation efficiency of methylene blue. For this purpose, two magnetite samples (M and N) were used and characterized by XRD, BET surface area, particle size analyzer and FE-SEM. Central composite design (CCD) was applied to design the experiments, develop regression models, optimize and evaluate the individual and interactive effects of five independent variables: H2O2 and catalyst concentrations, pH, …


Synthesis And Optimization Of Pedot:Pss Based Ink For Printing Nanoarrays Using Dip-Pen Nanolithography, Michal Wagner, Cathal O'Connell, David G. Harman, Ryan Sullivan, Ari Ivaska, Michael J. Higgins, Gordon G. Wallace Mar 2014

Synthesis And Optimization Of Pedot:Pss Based Ink For Printing Nanoarrays Using Dip-Pen Nanolithography, Michal Wagner, Cathal O'Connell, David G. Harman, Ryan Sullivan, Ari Ivaska, Michael J. Higgins, Gordon G. Wallace

Gordon Wallace

Due to the current interest in organic printable electronics, Dip-Pen Nanolithography (DPN) is increasingly being explored as a method to pattern electroactive materials such as conducting polymers (CPs) on the micro- and nanoscale. In general, printing process depends strongly on the ink-substrate properties and fundamental forces required to drive and stabilize the ink transfer to the substrate. Controlling these parameters is especially difficult when operating under the nanometer confinements of the DPN probe. For the printing of CPs, one step towards addressing these challenges is rational ink design, as the use of existing commercial-based inks may not be suitable for …


Effect Of Using Adjusted Parameters, Local And Global Optimums, For Phase Equilibrium Prediction On The Synthesis Of Azeotropic Distillation Columns, Claudia Gutierrez-Antonio, Andrea Ojeda-Gasca, Adrian Bonilla-Petriciolet, Juan Gabriel Segovia-Hernández, Abel Briones-Ramírez Jan 2014

Effect Of Using Adjusted Parameters, Local And Global Optimums, For Phase Equilibrium Prediction On The Synthesis Of Azeotropic Distillation Columns, Claudia Gutierrez-Antonio, Andrea Ojeda-Gasca, Adrian Bonilla-Petriciolet, Juan Gabriel Segovia-Hernández, Abel Briones-Ramírez

Adrian Bonilla-Petriciolet

We analyze the effect of using adjusted parameters, corresponding to local and global optimums, in the NRTL thermodynamic model on the complete process synthesis (design, optimization and control) of homogeneous azeotropic distillation columns. The adjusted parameters that corresponding to a global optimum were obtained with simulated annealing technique, while the adjusted parameters that corresponding to a local optimum were taken from Dechema Collection. Both sets of parameters were used to design a conventional sequence, a side-stream column and a Petlyuk sequence. These designs were used as initial solution to a multiobjective genetic algorithm with constraints handling, coupled to a processes …


Comparison Study Of Different Ionic Liquid Pretreatments In Maximizing Total Reducing Sugars Recovery, Kiat Moon Lee, Gek Cheng Ngoh Dr, Adeline Seak May Chua Dr, Li Wan Yoon, Teck Nam Ang Dr., Min Gyu Lee Prof Dec 2013

Comparison Study Of Different Ionic Liquid Pretreatments In Maximizing Total Reducing Sugars Recovery, Kiat Moon Lee, Gek Cheng Ngoh Dr, Adeline Seak May Chua Dr, Li Wan Yoon, Teck Nam Ang Dr., Min Gyu Lee Prof

Teck Nam Ang Dr.

A process scheme combining the most suitable ionic liquid pretreatment, followed by solid acid and enzymatic saccharification was used to maximize the reducing sugars recovery from sago waste. Three types of ionic liquids, i.e. 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), 1- ethyl-3-methylimidazolium acetate ([EMIM][OAc]) and 1-ethyl-3-methylimidazolium diethyl phosphate ([EMIM][(EtO)2PO2]) were evaluated based on their performance in terms of the total reducing sugars recovery, chemical cost, and pretreatment energy requirement. The results showed that all the ionic liquids assisted the saccharification processes by dissolving and depolymerizing the carbohydrates of the sago waste into shorter chain soluble oligosaccharides, as well as disrupting the biomass structure …


Wind Power Electric Systems: Modelization, Control And Optimization, Djamila Rekioua Pr Dec 2013

Wind Power Electric Systems: Modelization, Control And Optimization, Djamila Rekioua Pr

REKIOUA Djamila Dr

The book is organized through seven chapters as follows: • Chapter 1 is intended as an introduction to the subject. It defines the wind process, introduces the main meteorological elements, the wind velocity, and presents an overview of wind systems (stand-alone systems and grid connected systems). This chapter includes also pre-sizing and maintenance of wind systems. • Chapter 2 focuses on wind energy conversion and power electronics modeling. The different structures of converters used in wind systems are presented. Some applications are given under Matlab/Simulink. • In Chapter 3, a detailed review on the most used algorithms to track the …


Voltage Security Constrained Reactive Power Optimization Incorporating Wind Generation, L G. Meegahapola, E Vittal, A Keane, D Flynn Dec 2013

Voltage Security Constrained Reactive Power Optimization Incorporating Wind Generation, L G. Meegahapola, E Vittal, A Keane, D Flynn

Dr Lasantha G Meegahapola

This paper presents a comparative analysis between conventional optimal power flow (OPF) and voltage constrained OPF strategies with wind generation. The study has been performed using the New England 39 bus system with 12 doublyfed induction generator (DFIG) based wind farms installed across the network. A voltage security assessment is carried out to determine the critical wind farms for voltage stability enhancement. The power losses and individual wind farm reactive power generation have been compared with and without voltage stability constraints imposed on the OPF simulation. It is shown that voltage constrained OPF leads to much greater active power losses …


Optimizing The Sterilization Process Of Canned Food Using Temperature Distribution Studies, Ibrahim M. Ismail, Alaa Fahmy, Ahmed Azab, Magdy Abadir, Seif-Eddeen K. Fateen Dec 2013

Optimizing The Sterilization Process Of Canned Food Using Temperature Distribution Studies, Ibrahim M. Ismail, Alaa Fahmy, Ahmed Azab, Magdy Abadir, Seif-Eddeen K. Fateen

Seif-Eddeen K Fateen

The thermal processing of canned food is the most important step in the canning procedure. Retort operating procedures must ensure that uniform processing temperature is achieved and maintained throughout the locations of the canned containers during the process. In this study, temperature distribution tests have been used as a means of verifying the temperature uniformity around the containers. These studies were carried out in two Egyptian canning plants in horizontal water-immersion and water-spray retorts under fully loaded operating conditions. Time-temperature data gathered were used as a guidance tool in improving temperature distribution and in optimizing the process schedule.


Synthesis And Optimization Of Fluorine-Free Y And Cu Precursor Solution For Mod Processing Of Ybco Coated Conductor, Jaimoo Yoo, Young-Kuk Kim, Kookchae Chung, Jaewoong Ko, Xiaolin Wang, S X. Dou Jun 2013

Synthesis And Optimization Of Fluorine-Free Y And Cu Precursor Solution For Mod Processing Of Ybco Coated Conductor, Jaimoo Yoo, Young-Kuk Kim, Kookchae Chung, Jaewoong Ko, Xiaolin Wang, S X. Dou

Shi Xue Dou

MOD solutions for YBCO coated conductors were synthesized with fluorine-free Y & Cu precursor. The fluorine content in the precursor solution was significantly reduced and a fast calcination profile was realized. A crack-free & thick precursor film was successfully obtained just after less than 2 hours of calcination in wet O2 atmosphere. Optimization of the precursor solution with Sm addition enables further improvement of thickness and uniformity of precursor films. The calcinated precursor film was successfully converted to dense and uniform YBCO film after annealing in wet Ar/O2 atmosphere. The measured critical current value was about 273 A/cm-w (Jc ~ …


Optimization Of Welding Parameters For Repairing Nial Bronze Components, Huijun Li, Daniel Grudgings, Nathan P. Larkin, John Norrish, Mark Callaghan, Lenka Kuzmikova May 2013

Optimization Of Welding Parameters For Repairing Nial Bronze Components, Huijun Li, Daniel Grudgings, Nathan P. Larkin, John Norrish, Mark Callaghan, Lenka Kuzmikova

Nathan Larkin

The objective of this study is to determine an optimal welding procedure that can be implemented to repair damaged Nickel Aluminium Bronze (NAB) components. NAB is commonly used in marine applications where components are subject to a constant corrosive environment and high stresses. Research into ideal NAB microstructure for a marine application, was performed in order to gain a baseline for experimental analysis of potential welding procedures. The results indicated that the welding repair can be performed with a wide range of heat input. The effect of post-weld heat treatment (PWHT) on the microstructure and mechanical properties in the heat …


Multiobjective Plan Selection Optimization For Traffic Responsive Control, Montasir M. Abbas, Anuj Sharma Apr 2013

Multiobjective Plan Selection Optimization For Traffic Responsive Control, Montasir M. Abbas, Anuj Sharma

Anuj Sharma

Optimal coordination of traffic signals requires proper activation of timing plans to match current traffic conditions. One of the greatest challenges in configuring a traffic responsive plan selection control mode is how to select only n number of timing plans (restricted by traffic controller memory limitations) to address possibly all traffic conditions/states that can be encountered in the field, for a specific site, but most importantly, how to associate each of these traffic conditions to one of the n timing plans stored in the traffic controller. This paper uses a multiobjective non-dominated sorting genetic algorithm to (1) select the best …