Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 35 for “"Class F"”.
-
Class-F Power Amplifier with Maximized PAE
… of power with less DC power consumed. Non-linear Class-F and Class-F-1 PAs have drawn the most attention among all different classes of PAs from engineers because of their capability of outputting high power and providing good PAE. Class-F boosts up PAE by controlling the harmonic content at the …
-
Gallium nitride class-F power amplifier for UMTSWCDMA applications
… efficiency. In this thesis, a highly efficient class F power amplifier has been designed for WCDMA band with a center frequency of 2.14 GHz and bandwidth of 5 MHz using GaN transistor. The amplifier has been simulated using a high frequency circuit simulator namely, the Agilent Advanced Design …
-
Efficiency Improvement of WCDMA Base Station Transmitters using Class-F power amplifiers
… and efficiency. As a result of this trade-off a Class-AB power amplifier is most often used in QPSK based systems. Class-AB power amplifiers provide acceptable linearity at efficiency values around 45-50% typically. This compromise is not a satisfactory solution but is inevitable while using …
-
Benefit-Cost Analysis Of Using Class F Fly Ash-Based Green Cement In Masonry Units
<p>ABSTRACT</p> <p>BENEFIT-COST ANALYSIS OF USING CLASS F FLY ASH-BASED GREEN CEMENT IN MASONRY UNITS </p> <p>by</p> <p>KHALED SHWEKAT</p> <p>August 2015</p> <p>Advisor: Dr. Hwai-Chung Wu</p> <p>Major: Civil engineering</p> <p>Degree: Doctor of Philosophy</p> <p> The Portland cement concrete is the …
-
Development and performance of class F fly ash based geopolymer concretes against sulphuric acid attack
Geopolymer concretes synthesised from composite class F fly ashes and a mixed alkaline activator were optimised by use of Taguchi orthogonal design method. The optimised mix achieved a compressive strength at the age of 28 days of 70 and 58 MPa after initial curing at 70°C for 12 hours and at 23°C …
-
Exploring strengthening mechanisms for Class C and Class F fly ash in load bearing floor tile applications
… final product is a fly ash tile composed of two classes of fly ash, water, and several additives to strengthen the material. Standard ASTM tests were conducted. This fly ash tile is an energy efficient clay-tile alternative that excels in many mechanical properties.
-
Development of High performance Concrete Composites Using Class F Fly Ash and PCC Bottom Ash, and a Statistical Model to Predict Compressive Strength of Similar Concrete Composites
… OF HIGH PERFORMANCE CONCRETE COMPOSITES USING CLASS F FLY ASH AND PCC BOTTOM ASH, AND A STATISTICAL MODEL TO PREDICT COMPRESSIVE STRENGTH OF SIMILAR CONCRETE COMPOSITES ADVISOR: Dr. Sanjeev Kumar It is a common knowledge that the use of concrete is as old as the evolution of human civilization. …
-
Performance Comparison of Harmonically Tuned Power Amplifiers at 28 GHz in SiGe BiCMOS
… three single-stage power amplifiers (PAs): class-AB, class-F and inverse class-F (class-F-1) at 28 GHz. The PAs have identical input networks: input matching, base DC feed, and base stabilizing networks. At the load side, there is a different load network for each PA. Class-AB PA load …
-
Millimeter-Wave Harmonically-Tuned Silicon Power Amplifiers for High Efficiency
… demonstrates the feasibility of the inverse-Class-F harmonic tuning approach for mm-wave silicon PAs. This research addresses the challenges and limitations of the high efficiency inverse-Class-F PAs for mm-wave silicon technology. This work proposes different load networks to mitigate the …
-
Radio frequency power amplifiers for portable communication systems
… is to be conserved. Conventional amplifier classifications and definitions are presented in a unified and concise format. The Bipolar Junction Transistor (BJT) and Metal-Semiconductor Field Effect Transistor (MESFET) are evaluated as active devices in high-efficiency RF PA designs. Two …
-
Microstructure, Quasi-Static, And High-Strain Rate Dynamic Characterization Of Metakaolin And Fly Ash Based Geopolymers For Structural Applications
Geopolymers are a class of rapid setting cementing systems that have been used as mortar or additives in concrete mixes to improve properties. Several types of geopolymer systems such as metakaolin and fly ash based geopolymers are widely used, and are available in different mixture proportions [1, …
-
High performance Deep Learning based Digital Pre-distorters for RF Power Amplifiers
… their performance with simulation results on class-AB and class-F⁻¹ PAs. The simulation results show that both the learning methods lead to an improvement of more than 12 dB and 11dB in the linearity of class-AB and class-F⁻¹ PAs respectively, with indirect learning DL-DPD offering marginally …
-
Mechanical characteristics of organically modified fly ash-kaolinite mixtures
… lack of pozzolanic properties, the reuse rate of Class F fly ash in geotechnical engineering is relatively low (ACAA 2013). In order to promote the effectiveness and sustainability of high volume reuse of class F fly ash in geotechnical engineering, biopolymers (Chitosan, and Xanthan gum) and …
-
Activation mechanisms of non-class A G protein-coupled receptors
… entire body and are one of the most important classes of drug targets. While the majority of the recent literature on GPCRs focuses on Class A GPCRs, the structural and dynamic insights underlying the activation mechanism of non-Class A GPCRs are lacking. This thesis addresses this gap by …
-
EFFECT OF CRACK-REDUCING TECHNOLOGIES AND SUPPLEMENTARY CEMENTITIOUS MATERIALS ON SETTLEMENT CRACKING OF PLASTIC CONCRETE AND DURABILITY PERFORMANCE OF HARDENED CONCRETE
… containing different volume replacements of Class F and Class C fly ash and different combinations of a rheology-modifying admixture (RMA) with and without Class C fly. Program 3 involved concrete containing different dosage rates of one of two shrinkage compensating admixtures, one based on …
-
Alkali Silica Reaction Mitigation Using High Volume Class C Fly Ash
… was to develop preventative measures using Class C fly ash in concrete, which contains the moderately reactive aggregates found in the Arkansas River.</p> <p>The research used locally available fly ashes in order to represent the materials used in conjunction with the Arkansas River fine …
-
Hydrothermal synthesis and optimisation of zeolite Na-P1 from South African coal fly ash
… most of the studies have concentrated on class C fly ash and very few have reported the use of South African class F fly ash as feedstock for zeolite synthesis.Class F fly ash from South Africa has been confirmed to be a good substrate for zeolite synthesis due to its compositional …
-
CO2 sequestration using brine impacted fly fish
… that South African FA from Secunda belongs to class F based on the CaO content as well as the total alumina, silica and ferric oxide content, while the RO brine from Tutuka were classified as NaSO4 waters.
-
The Teaching of Children's Poetry: An Exploration of Instructional Practices in University Courses of Children's Literature, English, Language Arts, and Reading Education
… professors and adjunct instructors, their in-class instructional practices, and the types of poetry assignments given. Additionally, this study revealed both the poets typically highlighted and the goals held by professors and instructors in courses of children's literature, English, language …
-
Shear Strength Parameters of Sand Fly Ash Cement Mixtures
… the valuable by-product fly ash. There are three classes of fly ash: cementitious class C and non-cementitious classes F and N. Over half of the fly ash produced is used in the geotechnical/construction industries. Most geotechnical soil stabilization studies using fly ash are focused on …
Page 1 of 2