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The Effect Of Heat On The Metallurgical Structure And B-H Characteristic Of (Stator) Armature With Iron-Silicon Alloy In Electric Machines, FEVZİ KENTLİ, ÜMİT KEMALETTİN TERZİ 2010 TÜBİTAK

The Effect Of Heat On The Metallurgical Structure And B-H Characteristic Of (Stator) Armature With Iron-Silicon Alloy In Electric Machines, Fevzi̇ Kentli̇, Ümi̇t Kemaletti̇n Terzi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Coils in electric machines are varnished for insulation after winding. These varnished coils are formed in stiff construction in slots. Under heavy-duty operating conditions, all or part of some coils may be burnt or broken. Thermal method is one of several ways to remove the defective coils. In this method, current is passed through the defective coils by an autotransformer (variac) until all the varnish of the coils is burned. If all the coils are out of order, the varnish is burned by replacing the stator or armature in a burning room. Consequently, defective coils in the stator (armature) slots …


Analysis And Estimation Of Motion Transmission Errors Of A Timing Belt Drive, ERGİN KILIÇ, MELİK DÖLEN, AHMET BUĞRA KOKU 2010 TÜBİTAK

Analysis And Estimation Of Motion Transmission Errors Of A Timing Belt Drive, Ergi̇n Kiliç, Meli̇k Dölen, Ahmet Buğra Koku

Turkish Journal of Electrical Engineering and Computer Sciences

This paper focuses on viable position estimation schemes for timing belt drives where the position of the carriage (load) is to be determined via reference models receiving input from a position sensor attached to the actuator of the timing belt. A detailed analysis of the transmission error sources is presented, and a number of relevant mathematical models are developed using a priori knowledge of the process. This paper demonstrates that such schemes are very effective when the drive system is not subjected to external loads and operating conditions do not change considerably i.e. ambient temperature, belt tension.


Design Of Optimal Sampling Times For Pharmacokinetic Trials Via Spline Approximation, MUSA HAKAN ASYALI 2010 TÜBİTAK

Design Of Optimal Sampling Times For Pharmacokinetic Trials Via Spline Approximation, Musa Hakan Asyali

Turkish Journal of Electrical Engineering and Computer Sciences

Understanding and comparison of different drug delivery formulations are based on pharmacokinetic parameters (PKP) such as area under curve, maximum concentration, and time to reach maximum concentration. Accurate estimation of PKP is of critical importance in capturing drug absorption and elimination characteristics and in reaching bioequivalence decisions. Since PKP are estimated from a limited number of samples, the timing of the samples directly influences the accuracy of estimation. Optimization of the sampling times may not only increase the accuracy of PKP estimation, but also reduce the number of samples to be drawn, which in turn lessens the inconvenience to the …


Introducing Communication In Dis-Pomdps With Locality Of Interaction, Makoto TASAKI, Yuichi Yabu, Yuki Iwanari, Makoto Yokoo, Janusz Marecki, Pradeep Reddy VARAKANTHAM, Milind Tambe 2010 Kyushu University

Introducing Communication In Dis-Pomdps With Locality Of Interaction, Makoto Tasaki, Yuichi Yabu, Yuki Iwanari, Makoto Yokoo, Janusz Marecki, Pradeep Reddy Varakantham, Milind Tambe

Research Collection School Of Computing and Information Systems

The Networked Distributed POMDPs (ND-POMDPs) can model multiagent systems in uncertain domains and has begun to scale-up the number of agents. However, prior work in ND-POMDPs has failed to address communication. Without communication, the size of a local policy at each agent within the ND-POMDPs grows exponentially in the time horizon. To overcome this problem, we extend existing algorithms so that agents periodically communicate their observation and action histories with each other. After communication, agents can start from new synchronized belief state. Thus, we can avoid the exponential growth in the size of local policies at agents. Furthermore, we introduce …


Periodic Resource Reallocation In Two-Echelon Repairable Item Inventory Systems, Hoong Chuin LAU, Jie Pan, Huawei SONG 2010 Singapore Management University

Periodic Resource Reallocation In Two-Echelon Repairable Item Inventory Systems, Hoong Chuin Lau, Jie Pan, Huawei Song

Research Collection School Of Computing and Information Systems

Given an existing stock allocation in an inventory system, it is often necessary to perform reallocation over multiple time points to address inventory imbalance and maximize availability. In this paper, we focus on the situation where there are two opportunities to perform reallocation within a replenishment cycle. We derive a mathematical model to determine when and how to perform reallocation. Furthermore, we consider the extension of this model to the situation allowing an arbitrary number of reallocations. Experimental results show that the two-reallocation approach achieves better performance compared with the single-reallocation approach found in the literature. We also illustrate how …


Treatment Guidelines For Pavement Preservation, Jusang Lee, Todd Shields 2010 Indiana Department of Transportation

Treatment Guidelines For Pavement Preservation, Jusang Lee, Todd Shields

JTRP Technical Reports

This project presents pavement treatment practice guidelines and a distress identification manual for the purpose of improving the INDOT pavement preservation practices. The treatment guidelines consist of 10 treatment types for asphalt pavements and composite pavements and 8 treatment types for Portland cement concrete pavement (PCCP). The treatment guidelines include treatment descriptions, benefits, applicable pavement conditions, treatment materials, and treatment procedures. The guidelines are based on information obtained mainly from the INDOT Standard Specification, the INDOT Design Manual, and the INDOT Field Operations Handbook for Crew Leaders. The treatments are covered in the guidelines. The distress identification manual presents the …


Effect Of Pre-Processing On Binarization, Elisa Barney Smith, Laurence Likforman-Sulem, Jérôme Darbon 2010 Boise State University

Effect Of Pre-Processing On Binarization, Elisa Barney Smith, Laurence Likforman-Sulem, Jérôme Darbon

Electrical and Computer Engineering Faculty Publications and Presentations

The effects of different image pre-processing methods for document image binarization are explored. They are compared on five different binarization methods on images with bleed through and stains as well as on images with uniform background speckle. The binarization method is significant in the binarization accuracy, but the pre-processing also plays a significant role. The Total Variation method of pre-processing shows the best performance over a variety of pre-processing methods.


Influence Of Unstable Soil Movement On Pile-Founded Concrete Floodwalls And A Resulting Design Methodology, Richard James Varuso 2010 Louisiana State University and Agricultural and Mechanical College

Influence Of Unstable Soil Movement On Pile-Founded Concrete Floodwalls And A Resulting Design Methodology, Richard James Varuso

LSU Doctoral Dissertations

Efforts are underway in the New Orleans area to raise the elevations of its levee system to combat the effects of hurricane storm surge. When complete, the majority of the system will be comprised of a combination of levees, sheet pile I-Walls, floodgates, and pile-supported concrete floodwalls, commonly referred to as T-Walls. Given the magnitude of the hydrostatic forces associated with storm surge, global instability is failure mechanism that must be considered in the design of T-Walls. In the past, it was assumed that these forces would be resisted by the T-Wall’s sheet pile cut-off wall. Recent literature review and …


Determination Of Thermal Properties Using Embedded Thermocouples, Nicholas Anthony Lister 2010 UTSI

Determination Of Thermal Properties Using Embedded Thermocouples, Nicholas Anthony Lister

Masters Theses

The Purpose of this thesis is to experimentally demonstrate an inversion analysis technique, developed by Dr. Jay Frankel (UTK), that utilizes transient temperature data from probes embedded at known locations in a material. This allows one to determine thermal properties (thermal diffusivity and thermal conductivity) of the material, surface temperature, and the surface heat flux as they change with time. Dr. Frankel’s inversion method can be used to determine surface temperature and heat flux of a one-dimensional semi-infinite slab based on the transient data from one or two embedded probes, if the thermal conductivity and thermal diffusivity of the material …


Characterization Of Aluminum Doped Zinc Oxide Thin Films For Photovoltaic Applications, Bojanna P. Shantheyanda 2010 University of Central Florida

Characterization Of Aluminum Doped Zinc Oxide Thin Films For Photovoltaic Applications, Bojanna P. Shantheyanda

Electronic Theses and Dissertations

Growing demand for clean source of energy in the recent years has increased the manufacture of solar cells for converting sun energy directly into electricity. Research has been carried out around the world to make a cheaper and more efficient solar cell technology by employing new architectural designs and developing new materials to serve as light absorbers and charge carriers. Aluminum doped Zinc Oxide thin film, a Transparent conductive Oxides (TCO) is used as a window material in the solar cell these days. Its increased stability in the reduced ambient, less expensive and more abundance make it popular among the …


Validation Of Wideband Ocean Emissivity Radiative Transfer Model, Sonya Crofton 2010 University of Central Florida

Validation Of Wideband Ocean Emissivity Radiative Transfer Model, Sonya Crofton

Electronic Theses and Dissertations

Radiative Transfer Models (RTM) have many applications in the satellite microwave remote sensing field, such as the retrieval of oceanic and atmospheric environmental parameters, including surface wind vectors and sea surface temperatures, integrated water vapor, cloud liquid, and precipitation. A key component of the ocean RTM is the emissivity model used to determine the brightness temperature (Tb) at the ocean’s surface. A new wideband ocean emissivity RTM developed by the Central Florida Remote Sensing Laboratory (CFRSL) calculates ocean emissivity over a wide range of frequencies, incidence angles, sea surface temperatures (SST), and wind speed. This thesis presents the validation of …


Nonlinear Absorption And Free Carrier Recombination In Direct Gap Semiconductors, Peter D. Olszak 2010 University of Central Florida

Nonlinear Absorption And Free Carrier Recombination In Direct Gap Semiconductors, Peter D. Olszak

Electronic Theses and Dissertations

Nonlinear absorption of Indium Antimonide (InSb) has been studied for many years, yet due to the complexity of absorption mechanisms and experimental difficulties in the infrared, this is still a subject of research. Although measurements have been made in the past, a consistent model that worked for both picosecond and nanosecond pulse widths had not been demonstrated. In this project, temperature dependent two-photon (2PA) and free carrier absorption (FCA) spectra of InSb are measured using femtosecond, picosecond, and nanosecond IR sources. The 2PA spectrum is measured at room temperature with femtosecond pulses, and the temperature dependence of 2PA and FCA …


Conventional And Zvt Synchronous Buck Converter Design, Analysis, And Measurement, Mark Cory 2010 University of Central Florida

Conventional And Zvt Synchronous Buck Converter Design, Analysis, And Measurement, Mark Cory

Electronic Theses and Dissertations

The role played by power converting circuits is extremely important to almost any electronic system built today. Circuits that use converters of any type depend on power that is consistent in form and reliable in order to properly function. In addition, today's demands require more efficient use of energy, from large stationary systems such as power plants all the way down to small mobile devices such as laptops and cell phones. This places a need to reduce any losses to a minimum. The power conversion circuitry in a system is a very good place to reduce a large amount of …


Analyzing Instructtion Based Cache Replacement Policies, Ping Xiang 2010 University of Central Florida

Analyzing Instructtion Based Cache Replacement Policies, Ping Xiang

Electronic Theses and Dissertations

The increasing speed gap between microprocessors and off-chip DRAM makes last-level caches (LLCs) a critical component for computer performance. Multi core processors aggravate the problem since multiple processor cores compete for the LLC. As a result, LLCs typically consume a significant amount of the die area and effective utilization of LLCs is mandatory for both performance and power efficiency. We present a novel replacement policy for last-level caches (LLCs). The fundamental observation is to view LLCs as a shared resource among multiple address streams with each stream being generated by a static memory access instruction. The management of LLCs in …


Hurricane Wind Speed And Rain Rate Measurements Using The Airborne Hurricane Imaging Radiometer (Hirad), Ruba Amarin 2010 University of Central Florida

Hurricane Wind Speed And Rain Rate Measurements Using The Airborne Hurricane Imaging Radiometer (Hirad), Ruba Amarin

Electronic Theses and Dissertations

This dissertation presents results for an end-to-end computer simulation of a new airborne microwave remote sensor, the Hurricane Imaging Radiometer, HIRAD, which will provide improved hurricane surveillance. The emphasis of this research is the retrieval of hurricane-force wind speeds in the presence of intense rain and over long atmospheric slant path lengths that are encountered across its wide swath. Brightness temperature (Tb) simulations are performed using a forward microwave radiative transfer model (RTM) that includes an ocean surface emissivity model at high wind speeds developed especially for HIRAD high incidence angle measurements and a rain model for the hurricane environment. …


High Heat Flux Spray Cooling With Ammonia On Enhanced Surfaces, Huseyin Bostanci 2010 University of Central Florida

High Heat Flux Spray Cooling With Ammonia On Enhanced Surfaces, Huseyin Bostanci

Electronic Theses and Dissertations

Many critical applications today, in electronics, optics and aerospace fields, among others, demand advanced thermal management solutions for the acquisition of high heat loads they generate in order to operate reliably and efficiently. Current competing technologies for this challenging task include several single and two phase cooling options. When these cooling schemes are compared based on the high heat flux removal (100-1000 W/cm2) and isothermal operation (within several oC across the cooled device) aspects, as well as system mass, volume and power consumption, spray cooling appears to be the best choice. The current study focused on high heat flux spray …


Numerical Modeling Of The Shock Tube Flow Fields Before Andduring Ignition Delay Time Experiments At Practical Conditions, mouna lamnaouer 2010 University of Central Florida

Numerical Modeling Of The Shock Tube Flow Fields Before Andduring Ignition Delay Time Experiments At Practical Conditions, Mouna Lamnaouer

Electronic Theses and Dissertations

An axi-symmetric shock-tube model has been developed to simulate the shock-wave propagation and reflection in both non-reactive and reactive flows. Simulations were performed for the full shock-tube geometry of the high-pressure shock tube facility at Texas A&M University. Computations were carried out in the CFD solver FLUENT based on the finite volume approach and the AUSM+ flux differencing scheme. Adaptive mesh refinement (AMR) algorithm was applied to the time-dependent flow fields to accurately capture and resolve the shock and contact discontinuities as well as the very fine scales associated with the viscous and reactive effects. A conjugate heat transfer model …


Experimental And Cfd Investigations Of Lifted Tribrachial Flames, Zhiliang Li 2010 University of Central Florida

Experimental And Cfd Investigations Of Lifted Tribrachial Flames, Zhiliang Li

Electronic Theses and Dissertations

Experimental measurements of the lift-off velocity and lift-off height, and numerical simulations were conducted on the liftoff and stabilization phenomena of laminar jet diffusion flames of inert-diluted C3H8 and CH4 fuels. Both non-reacting and reacting jets were investigated, including effects of multi-component diffusivities and heat release (buoyancy and gas expansion). The role of Schmidt number for non-reacting jets was investigated, with no conclusive Schmidt number criterion for liftoff previously known in similarity solutions. The cold-flow simulation for He-diluted CH4 fuel does not predict flame liftoff; however, adding heat release reaction leads to the prediction of liftoff, which is consistent with …


On The Use Of Polyurethane Matrix Carbon Fiber Composites For Strengthening Concrete Structures, Zachary Haber 2010 University of Central Florida

On The Use Of Polyurethane Matrix Carbon Fiber Composites For Strengthening Concrete Structures, Zachary Haber

Electronic Theses and Dissertations

Fiber-reinforced polymer (FRP) composite materials have effectively been used in numerous reinforced concrete civil infrastructure strengthening projects. Although a significant body of knowledge has been established for epoxy matrix carbon FRPs and epoxy adhesives, there is still a need to investigate other matrices and adhesive types. One such matrix/adhesive type yet to be heavily researched for infrastructure application is polyurethane. This thesis investigates use of polyurethane matrix carbon fiber composites for strengthening reinforced concrete civil infrastructure. Investigations on mirco- and macro-mechanical composite performance, strengthened member flexural performance, and bond durability under environmental conditioning will be presented. Results indicate that polyurethane …


Impact Of Hurricanes On Structures - A Performance Based Engineering View, Vijay Mishra 2010 University of Central Florida

Impact Of Hurricanes On Structures - A Performance Based Engineering View, Vijay Mishra

Electronic Theses and Dissertations

The magnitude of damage caused to the United States (US) coast due to hurricanes has increased significantly in the last decade. During the period 2004-2005, the US experienced seven of the costliest hurricanes in the country's history (NWS TPC-5, 2007) leading to an estimated loss of ~ $158 billion. The present method for predicting hurricane losses, HAZUS (HAZard US), is solely based on hurricane hazard and damage caused to building envelopes only and not to structural systems (Vickery et al., 2006). This method does not take into account an intermediate step that allows for better damage estimates, which is structural …


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