Electrical and Computer Engineering Commons^™

Wlan Based Indoor Localization, Sreejith Sisupalan Lathikumari

Electrical Engineering Theses - Archive

Localization based on received signal strength has been a topic of Interest due to its relative simplicity in measurement and minimal hardware requirements. Much of the research in this field has been on developing an indoor propagation model. A generic indoor propagation model has largely been unsuccessful due to the complex multipath environment present in indoor environments. The main focus of this study is to find the position of the target when the estimated distance from the measurement points are known. The straightforward approach to this problem is by using trilateration techniques. A novel weighted centroid based method is introduced …

Pilot Based Channel Estimation For 3gpp Lte Downlink, Ankit Ashok Agarwal

Electrical Engineering Theses - Archive

Channel estimation is an important part for the design of receivers in mobile communication systems. In order to recover the transmitted information correctly, the effect of the channel on the transmitted signal must be correctly estimated. In this thesis, the pilot based channel estimation algorithms for 3GPP LTE downlink is studied. Channel estimation algorithms such as Least Square (LS), Minimum Mean Square Error (MMSE) and Modified MMSE (M-MMSE) channel estimation algorithm have been evaluated for LTE downlink 5 MHz bandwidth configuration. The performance of these algorithms for Block type and Comb type pilot arrangement has been measured in terms of …

Second Order Training Algorithms For Radial Basis Function Neural Networks, Kanishka Tyagi

Electrical Engineering Theses - Archive

A systematic two step batch approach for constructing and training of Radial basis function (RBF) neural networks is presented. Unlike other RBF learning algorithms, the proposed paradigm uses optimal learning factors (OLF's) to train the network parameters, i.e. spread parameters, mean vector parameters and weighted distance measure (DM) coefficients. Newton's algorithm is proposed for obtaining multiple optimal learning factors (MOLF) for the network parameters. The weights connected to the output layer are trained by a supervised-learning algorithm based on orthogonal least squares (OLS). The error obtained is then back-propagated to tune the RBF parameters. The proposed hybrid training algorithm has …

A Planar And Integrated Rectenna For Wireless Power Reception, Vinay Ramachanndra Gowda

Electrical Engineering Theses - Archive

In this thesis, a rectenna ("rectifier + antenna") for wireless power reception is designed and experimentally verified. The rectenna consists of two major components: one is a microstrip patch antenna and the other is a half-wave rectifier circuit. The microstrip antenna collects wireless power, and then, the received radio-frequency power is rectified to DC by the rectifier. The microstrip antenna and the rectifier circuit are simulated, fabricated, and tested separately. Before they are integrated, matching network is designed in between them to match the first harmonic. A few integrated rectenna's are built around 2.4 GHz ISM band. The rectenna's are …

Behavioural Analysis Of Thermal Actuator Made Up Of Metals Like Titanium, Stainless Steel And Brass, Praveen Balaji Thangamani Balasubramanian

Electrical Engineering Theses - Archive

Out of the various MEMS actuators, thermal actuators are easy to realize and creates more force by consuming less power compared with other types of MEMS based actuators [2]-[4].Conventional thermal actuators are made up of poly silicon which requires the use of costlier equipment's for its fabrication and further it has to go through dark room processing which is time consuming. In our system the thermal actuator are made up of metals like titanium, stainless steel and brass which were fabricated using a programmable 5-W 355-nm laser system, which makes the fabrication process cheaper and less time consuming. Performance of …

Using Thermally Coupled Reactive Distillation Columns In Biodiesel Production, Nghi Nguyen, Yaşar Demirel

Yaşar Demirel Publications

Production of ethyl dodecanoate (biodiesel) using lauric acid and methanol with a solid acid catalyst of sulfated zirconia is studied by using two distillation sequences. In the first sequence, the methanol recovery column follows the reactive distillation column. In the second sequence, the reactive distillation and methanol recovery columns are thermally coupled. Thermally coupled distillation sequences may consume less energy by allowing interconnecting vapor and liquid streams between the two columns to elminate reboiler or condenser or both. Here we study the thermally coupled side-stripper reactive distillation and eliminate the condenser of the reactive distillation column. Both the sequences are …

Investigation Of Reactively Sputtered Boron Carbon Nitride Thin Films, Vinit O. Todi

Electronic Theses and Dissertations

Research efforts have been focused in the development of hard and wear resistant coatings over the last few decades. These protective coatings find applications in the industry such as cutting tools, automobile and machine part etc. Various ceramic thin films like TiN, TiAlN, TiC, SiC and diamond-like carbon (DLC) are examples of the films used in above applications. However, increasing technological and industrial demands request thin films with more complicated and advanced properties. For this purpose, B-C-N ternary system which is based on carbon, boron and nitrogen which exhibit exceptional properties and attract much attention from mechanical, optical and electronic …

Exploiting Opponent Modeling For Learning In Multi-Agent Adversarial Games, Kennard R. Laviers

Electronic Theses and Dissertations

An issue with learning effective policies in multi-agent adversarial games is that the size of the search space can be prohibitively large when the actions of both teammates and opponents are considered simultaneously. Opponent modeling, predicting an opponent’s actions in advance of execution, is one approach for selecting actions in adversarial settings, but it is often performed in an ad hoc way. In this dissertation, we introduce several methods for using opponent modeling, in the form of predictions about the players’ physical movements, to learn team policies. To explore the problem of decision-making in multi-agent adversarial scenarios, we use our …

Multiagent Learning Through Indirect Encoding, David B. D'Ambrosio

Electronic Theses and Dissertations

Designing a system of multiple, heterogeneous agents that cooperate to achieve a common goal is a difficult task, but it is also a common real-world problem. Multiagent learning addresses this problem by training the team to cooperate through a learning algorithm. However, most traditional approaches treat multiagent learning as a combination of multiple single-agent learning problems. This perspective leads to many inefficiencies in learning such as the problem of reinvention, whereby fundamental skills and policies that all agents should possess must be rediscovered independently for each team member. For example, in soccer, all the players know how to pass and …

Lyapunov-Based Control Design For Uncertain Mimo Systems, Zhao Wang

Electronic Theses and Dissertations

In this dissertation. we document the progress in the control design for a class of MIMO nonlinear uncertain system from five papers. In the first part, we address the problem of adaptive control design for a class of multi-input multi-output (MIMO) nonlinear systems. A Lypaunov based singularity free control law, which compensates for parametric uncertainty in both the drift vector and the input gain matrix, is proposed under the mild assumption that the signs of the leading minors of the control input gain matrix are known. Lyapunov analysis shows global uniform ultimate boundedness (GUUB) result for the tracking error under …

Integration Of High-Q Filters With Highly Efficient Antennas, Yazid Yusuf

Electronic Theses and Dissertations

The integration of high-quality (Q)-factor 3-D filters with highly efficient antennas is addressed in this dissertation. Integration of filters and antennas into inseparable units eliminates the transitions between the otherwise separate structures resulting in more compact and efficient systems. The compact, highly efficient integrated 3-D filter/antenna systems, enabled by the techniques developed herein, allow for the realization of integrated RF front ends with significantly- reduced form factors. Integration of cavity filters with slot antennas in a single planar substrate is first demonstrated. Due to the high Q factor of cavity resonators, the efficiency of the integrated filter/antenna system is found …

Exploring Techniques For Measurement And Improvement Of Data Quality With Application To Determination Of The Last Known Position (Lkp) In Search And Rescue (Sar) Data, Abhijit Wakchaure

Electronic Theses and Dissertations

There is a tremendous volume of data being generated in today’s world. As organizations around the globe realize the increased importance of their data as being a valuable asset in gaining a competitive edge in a fast-paced and a dynamic business world, more and more attention is being paid to the quality of the data. Advances in the fields of data mining, predictive modeling, text mining, web mining, business intelligence, health care analytics, etc. all depend on clean, accurate data. That one cannot effectively mine data, which is dirty, comes as no surprise. This research is an exploratory study of …

Analysis Of Behaviors In Crowd Videos, Ramin Mehran

Electronic Theses and Dissertations

In this dissertation, we address the problem of discovery and representation of group activity of humans and objects in a variety of scenarios, commonly encountered in vision applications. The overarching goal is to devise a discriminative representation of human motion in social settings, which captures a wide variety of human activities observable in video sequences. Such motion emerges from the collective behavior of individuals and their interactions and is a significant source of information typically employed for applications such as event detection, behavior recognition, and activity recognition. We present new representations of human group motion for static cameras, and propose …

Spectrum Sharing And Service Pricing In Dynamic Spectrum Access Networks, Swastik Kumar Brahma

Electronic Theses and Dissertations

Traditionally, radio spectrum has been statically allocated to wireless service providers (WSPs). Regulators, like FCC, give wireless service providers exclusive long term licenses for using specific range of frequencies in particular geographic areas. Moreover, restrictions are imposed on the technologies to be used and the services to be provided. The lack of flexibility in static spectrum allocation constrains the ability to make use of new technologies and the ability to redeploy the spectrum to higher valued uses, thereby resulting in inefficient spectrum utilization [23, 38, 42, 62, 67]. These limitations have motivated a paradigm shift from static spectrum allocation towards …

Global Secure Sets Of Trees And Grid-Like Graphs, Yiu Yu Ho

Electronic Theses and Dissertations

Let G = (V, E) be a graph and let S ⊆ V be a subset of vertices. The set S is a defensive alliance if for all x ∈ S, |N[x] ∩ S| ≥ |N[x] − S|. The concept of defensive alliances was introduced in [KHH04], primarily for the modeling of nations in times of war, where allied nations are in mutual agreement to join forces if any one of them is attacked. For a vertex x in a defensive alliance, the number of neighbors of x inside the alliance, plus the vertex x, is at least the number …

Low Noise, Narrow Optical Linewidth Semiconductor-Based Optical Comb Source And Low Noise Rf Signal Generation, Ibrahim Tuna Ozdur

Electronic Theses and Dissertations

Recently optical frequency combs and low noise RF tones are drawing increased attention due to applications in spectroscopy, metrology, arbitrary waveform generation, optical signal processing etc. This thesis focuses on the generation of low noise RF tones and stabilized optical frequency combs. The optical frequency combs are generated by a semiconductor based external cavity mode-locked laser with a high finesse intracavity etalon. In order to get the lowest noise and broadest bandwidth from the mode-locked laser, it is critical to know the free spectral range (FSR) of the etalon precisely. First the etalon FSR is measured by using the modified …

A Compact Physical Model For Morphology Induced Intrinsic Degradation Of Polymer Based Bulk Heterojunction Solar Cell, Biswajit Ray, Muhammad A. Alam

Birck and NCN Publications

The gradual loss of efficiency during field operation poses a fundamental challenge for economic viability of any solar cell technology. Well known examples include light-induced degradation in Si-based cell (Staebler-Wronski effect), Cu diffusion in thin film (CIGS) cell, hot-spot degradation in series connected modules, etc. Here we develop a compact model for an intrinsic degradation concern for bulk heterojunction type organic photovoltaic (BH-OPV) cells that involve continued (thermal) phase segregation of the donor-acceptor molecules leading to characteristic loss of efficiency and performance. Our approach interprets a number of BH-OPV device degradation measurements within a common framework and suggests/rationalizes intuitive routes …

Cdte/Cds Thin Film Solar Cells Fabricated On Flexible Substrates, Vasilios Palekis

USF Tampa Graduate Theses and Dissertations

Cadmium Telluride (CdTe) is a leading thin film photovoltaic (PV) material due to its near ideal bandgap of 1.45 eV and its high optical absorption coefficient. The typical CdTe thin film solar cell is of the superstrate configuration where a window layer (CdS), the absorber (CdTe) and a back contact are deposited onto glass coated with a transparent electrode.

Substrate CdTe solar cells where the above listed films are deposited in reverse are not common. In this study substrate CdTe solar cells are fabricated on flexible foils.

The properties of the Molybdenum back contact, Zinc Telluride (ZnTe) interlayer and CdTe …

Stress-Strain Management Of Heteroepitaxial Polycrystalline Silicon Carbide Films, Christopher William Locke

USF Tampa Graduate Theses and Dissertations

Silicon carbide (SiC) is one of the hardest known materials and is also, by good fortune, a wide bandgap semiconductor. While the application of SiC for high-temperature and high-power electronics is fairly well known, its utility as a highly robust, chemically-inert material for microelectrical mechanical systems (MEMS) is only beginning to be well recognized. SiC can be grown on both native SiC substrates or on Si using heteroepitaxial growth methods which affords the possibility to use Si micromachining methods to fabricate advanced SiC MEMS devices.

The control of film stress in heteroepitaxial silicon carbide films grown on polysilicon-on-oxide substrates has …

Implementation Of Complexity Reduction Algorithm For Intra Mode Selection In H.264/Avc, Santosh Kumar Muniyappa

Electrical Engineering Theses - Archive

For applications with low computational capabilities like handheld devices, it is necessary that the encoding complexity is minimal. But H.264, which is the most widely accepted video platform employs several powerful coding techniques that increase encoding complexity. Hence, the objective of this thesis is to implement an algorithm which reduces the encoding complexity by about 25%, but retains the quality of the existing intra prediction algorithm. H.264 offers nine modes for intra prediction of 4x4 luminance blocks, which includes DC prediction and eight directional modes (N4). For regions with less spatial detail, H.264 supports 16x16 intra coding, where in one …