Index Catalog // ScholarsArchive@OSU

Channel estimation and data detection for mobile MIMO OFDM systems

Creator:: Gao, Jie
Abstract:: Designing spectral efficient, high-speed wireless links that offer high quality- of-service and range capability has been a critical research and engineering challenge. In this thesis, we mainly address the complexity and performance issues of channel estimation and data detection in multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems over...
Resource Type:: Dissertation

Gray codes and their applications

Creator:: Anantha, Madhusudhanan
Abstract:: An n-bit Gray code is an ordered set of all 2n binary strings of length n. The special property of this listing is that Hamming distance between consecutive vectors is exactly 1. If the last and first codeword also have a Hamming distance 1 then the code is said to...
Resource Type:: Dissertation

Low-complexity high-speed VLSI design of low-density parity-check decoders

Creator:: Cui, Zhiqiang
Abstract:: Low-Density Parity-check (LDPC) codes have attracted considerable attention due to their capacity approaching performance over AWGN channel and highly parallelizable decoding schemes. They have been considered in a variety of industry standards for the next generation communication systems. In general, LDPC codes achieve outstanding performance with large codeword lengths (e.g.,...
Resource Type:: Dissertation

The dynamic speculation and performance prediction of parallel loops

Creator:: Zier, David A.
Abstract:: General purpose computer systems have seen increased performance potential through the parallel processing capabilities of multicore processors. Yet this potential performance can only be attained through parallel applications, thus forcing software developers to rethink how everyday applications are designed. The most readily form of Thread Level Parallelism (TLP) within any...
Resource Type:: Dissertation

Some communication algorithms for Gaussian and Eisenstein-Jacobi networks

Creator:: Albader, Bader
Abstract:: Interconnection networks play important roles in designing high performance computers. Recently two new classes of interconnection networks based on the concept of Gaussian and Eisenstein-Jacobi integers were introduced. In this research, efficient routing and broadcasting algorithms for these networks are developed. Furthermore, constructing edge disjoint Hamiltonian cycles in Gaussian networks...
Resource Type:: Dissertation

Design techniques for wideband low-power Delta-Sigma analog-to-digital converters

Creator:: Wang, Yan
Abstract:: Delta-Sigma (ΔΣ) analog-to-digital converters (ADCs) are traditionally used in high quality audio systems, instrumentation and measurement (I&M) and biomedical devices. With the continued downscaling of CMOS technology, they are becoming popular in wideband applications such as wireless and wired communication systems,high-definition television and radar systems. There are two general realizations...
Resource Type:: Dissertation

Limited magnitude error control codes

Creator:: Elarief, Noha
Abstract:: A relatively new model of error control is the limited magnitude error over high radix channels. In this error model, the error magnitude does not exceed a certain limit known beforehand. In this dissertation, we study systematic error control codes for common channels under the assumption that the maximum error...
Resource Type:: Dissertation

Energy-efficient, short-range ultra-wideband radio transceivers

Creator:: Hu, Changhui
Abstract:: Short-range wireless communications continually attract interest from both industry and academia, and it is changing our life in every aspect in the last decade. The design of wireless transceivers is the bottleneck for variety applications, due to RF modeling inaccuracy, stringent FCC regulations over the transmitted power spectrum, interference, multi-path...
Resource Type:: Dissertation

On shortest disjoint paths and Hamiltonian cycles in some interconnection networks

Creator:: Hussain, Zaid
Abstract:: Parallel processors are classified into two classes: shared-memory multiprocessors and distributed- memory multiprocessors. In the shared-memory system, processors communicate through a common memory unit. However, in the distributed multiprocessor system, each processor has its own memory unit and the communications among the processors are performed through an interconnection network. Thus,...
Resource Type:: Dissertation

Vehicle routing and scheduling with delivery and installation

Creator:: Kim, Kyoung Cheol
Abstract:: For manufacturing and service industries to stay competitive in this rapidly changing, globalized world, one of the most important operations, and one that many businesses struggle to plan and manage efficiently, is material handling. There has been a large amount of research on various vehicle routing problems (VRPs) in recent...
Resource Type:: Dissertation

Essays on determinants of human capital accumulation

Creator:: Sherpa, Maya
Abstract:: This dissertation is composed of two self-contained essays, which examine two different factors that could affect human capital accumulation in a developing country. Both essays utilize cross-sectional data from the second round (2003/04) of national level household survey from Nepal. In the first essay, I estimate the impact of remittances...
Resource Type:: Dissertation

Analysis and design on low-power multi-Gb/s serial links

Creator:: Hu, Kangmin
Abstract:: High speed serial links are critical components for addressing the growing demand for I/O bandwidth in next-generation computing applications, such as many-core systems, backplane and optical data communications. Due to continued process scaling and circuit innovations, today's CMOS serial link transceivers can achieve tens of Gb/s per pin. However, most...
Resource Type:: Dissertation

Efficient multiuser cooperative relay communications employing layered modulations

Creator:: Whang, Roderick Jaehoon
Abstract:: Relay-assisted cooperative communications are promising solutions for error-performance improvement and cell coverage extension. In this thesis, we propose several efficient cooperative relay communication schemes. First, an efficient space-time coded cooperative relay communications scheme that employs linear precoding and transmission-pattern selection is proposed. This is built upon an existing block linear...
Resource Type:: Dissertation

Applied color processing

Creator:: Zhang, Heng
Abstract:: The quality of a digital image pipeline relies greatly on its color reproduction which should at a minimum handle the color constancy, and the final judgment of the excellence of the pipeline is made through subjective observations by humans. This dissertation addresses a few topics surrounding the color processing of...
Resource Type:: Dissertation

Classifying seven dimensional manifolds of fixed cohomology type

Creator:: Montagantirud, Pongdate
Abstract:: Finding new examples of compact simply connected spaces admitting a Riemannian metric of positive sectional curvature is a fundamental problem in differential geometry. Likewise, studying topological properties of families of manifolds is very interesting to topologists. The Eschenburg spaces combine both of those interests: they are positively curved Riemannian manifolds...
Resource Type:: Dissertation

High efficiency wideband low-power delta-sigma modulators

Creator:: Lee, Sang Hyeon
Abstract:: Delta-sigma analog-to-digital converters traditionally have been used for low speed, high resolution applications such as measurements, sensors, voice and audio systems. Through continued device scaling in CMOS technology and architectural and circuit level design innovations, they have even become popular for wideband, high dynamic range applications such as wired and...
Resource Type:: Dissertation

Resource allocation methods for quality-of-service provisioning in heterogeneous wireless networks

Creator:: Chakchouk, Nessrine
Abstract:: The increased use of mobile wireless devices that we have recently been witnessing, such as smartphones, tablets, e-readers, and WiFi enabled devices in general, is driving an unprecedented increase in the amount of data traffic. This fast market adoption of the wireless technology along with the tremendous success of multimedia...
Resource Type:: Dissertation

Efficient detection and scheduling for MIMO-OFDM systems

Creator:: Liu, Wei
Abstract:: Multiple-input multiple-output (MIMO) antennas can be exploited to provide high data rate using a limited bandwidth through multiplexing gain. MIMO combined with orthogonal frequency division multiplexing (OFDM) could potentially provide high data rate and high spectral efficiency in frequency-selective fading channels. MIMO-OFDM technology has been widely employed in modern communication...
Resource Type:: Dissertation

A probabilistic framework and algorithms for modeling and analyzing multi-instance data

Creator:: Behmardi, Behrouz
Abstract:: Multi-instance data, in which each object (e.g., a document) is a collection of instances (e.g., word), are widespread in machine learning, signal processing, computer vision, bioinformatic, music, and social sciences. Existing probabilistic models, e.g., latent Dirichlet allocation (LDA), probabilistic latent semantic indexing (pLSI), and discrete component analysis (DCA), have been...
Resource Type:: Dissertation

Representations of fractional Brownian motion

Creator:: Wichitsongkram, Noppadon
Abstract:: Integral representations provide a useful framework of study and simulation of fractional Browian motion, which has been used in modeling of many natural situations. In this thesis we extend an integral representation of fractional Brownian motion that is supported on a bounded interval of ℝ to integral representation that is...
Resource Type:: Dissertation

Adiabatic and stable adiabatic times

Creator:: Bradford, Kyle B.
Abstract:: While the stability of time-homogeneous Markov chains have been extensively studied through the concept of mixing times, the stability of time-inhomogeneous Markov chains has not been studied as in depth. In this manuscript we will introduce special types of time-inhomogeneous Markov chains that are defined through an adiabatic transition. After...
Resource Type:: Dissertation

Security protocols for linear network coding

Creator:: Adeli, Majid
Abstract:: Network coding, as the next generation of data routing protocols, enables each intermediate node in a network to process and encode its received data before forwarding it to the next nodes. Hence, the core idea in network coding is to allow a network to encode the data that is being...
Resource Type:: Dissertation

Design techniques for low power high speed successive approximation analog-to-digital converters

Creator:: Lin, Jiaming
Abstract:: This dissertation presents two high-speed pipeline successive approximation analog-to-digital converters (SAR ADCs). Capacitive DACs and resistive DACs are utilized in these two pipeline SAR ADCs, respectively. The pipeline SAR ADC with capacitive DACs can save 50% switching power compared with other time-interleaved SAR ADCs since the total capacitance of the...
Resource Type:: Dissertation

Micropower incremental analog-to-digital converters

Creator:: Chen, Chia-Hung
Abstract:: Incremental ADCs (IADCs) have many advantages for low-frequency high-accuracy data conversion—they are easy to multiplex between channels, need simpler digital decimation filter, and allow extended counting with a Nyquist-rate ADC. A single-loop incremental ADC was designed and fabricated in 90 nm for a biosensor interface circuit. It incorporates one integrator,...
Resource Type:: Dissertation

Low-power successive approximation analog to digital converter with digital calibration

Creator:: Li, Wei
Abstract:: IC designers are continuously facing the challenges from reduced CMOS feature sizes and supply voltages. ADCs that deliver satisfactory resolutions/speeds while utilizing the state-of-the-art technologies to save power are in high demand. The analog circuits are more and more assisted by various digital calibration techniques to get boosted performances. This...
Resource Type:: Dissertation

A remotely operated, autonomous wave energy converter system

Creator:: Lewis, Timothy M.
Abstract:: The potential for electric energy generation from ocean waves is substantial and much research is being conducted on the conversion process as a renewable, grid-connected, power source. Some of the same attributes that make wave energy harvesting attractive as a grid-connected source also make it attractive as a remote, or...
Resource Type:: Dissertation

Design techniques for low-power electrical and optical serial link receivers

Creator:: Bai, Rui
Abstract:: As computation power continues to grow, the demand for data transfer bandwidth is also rising. This is reflected in the increasing data-rate of high-speed links. However, the increase in data-rate is sustainable only if the I/O energy efficiency improves as well. This dissertation explores several techniques to enable high-speed links...
Resource Type:: Dissertation

Position estimation in indoor localization system

Creator:: Qiao, Tianzhu
Abstract:: Indoor positioning systems can be used for many applications such as indoor navigation,emergence response, asset monitoring, and shopper assistance. Due to the weak received signal and multipath reflection, the global positioning system (GPS) generally does not work in indoor environments. There are a variety of radio frequency (RF) signals and...
Resource Type:: Dissertation

Offloading of I/O transactions in current CPU architectures

Creator:: Larsen, Steen K.
Abstract:: IO transactions within a computer system have evolved along with other system components (i.e., CPU, memory, video) from programmed IO (PIO). In current mainstream systems (spanning from HPC to mobile) the IO transactions are CPU-centric descriptor-based DMA transactions. The key benefit is that slower IO devices can DMA write system...
Resource Type:: Dissertation

Linearity enhancement techniques for data converters

Creator:: Cao, Jinzhou
Abstract:: Data converters are essential interface circuits between the analog world that people live in and the digital processors that people live with. Linearity, which often is a tradeoff against other performance criteria, is one of the major performance demands from applications for both analog-to-digital converts (ADC) and digital-to-analog converters (DAC)....
Resource Type:: Dissertation

Applications of Holographic Optical Tweezers: Multiplexed Fluorescence Spectroscopy and the Micromechanics of Type-I Collagen

Creator:: Cibula, Matthew A.
Abstract:: The development and some applications of holographic optical tweezers (HOT) are presented. Our HOT system uses a spatial light modulator (SLM) to control the location and properties of the optical trap. We have developed a method for optimizing the diffraction efficiency of a SLM that can be applied in situ...
Resource Type:: Dissertation

Evolutionary Approach to Efficient Provisioning and Self-organization in Wireless Sensor Networks (WSN)

Creator:: Khanna, Rahul, 1966-
Abstract:: Advances in low-power digital integration and microelectro-mechanical systems (MEMS) have paved the way for micro-sensors. These sensors are equipped with data processing capabilities along with sensory circuits. Sensor data are processed on these individual sensors and transmitted to the target (sink). Lowcost integration and small sizes of these sensors have...
Resource Type:: Dissertation

Transmission and Combining for Hybrid Automatic Repeat Request in Multiple-Input Multiple-Output Systems

Creator:: Whang, Younghoon
Abstract:: Hybrid automatic repeat request (HARQ) schemes combine packet retransmission with forward error correction to ensure a reliable communications. In multiple-input multiple output (MIMO) systems, interference cancellation (IC) detection is widely used where the detection and cancellation steps of the simultaneously transmitted data streams occur. In principle, the signal stream estimated...
Resource Type:: Dissertation

Quantum and Classical Simulation of Electronic Transport at the Nanoscale

Creator:: Gruss, Daniel S.
Abstract:: Time-dependent electronic transport is increasingly important to the state-of-the-art device design and fabrication. The development of nanoscale sensing, the harnessing and control of structural fluctuations, and the advancement of next-generation materials all require a treatment of quantum dynamics beyond the level of traditional methods and a more nuanced approach to...
Resource Type:: Dissertation

New Families of pseudo-Anosov Homeomorphisms with Vanishing Sah-Arnoux-Fathi Invariant

Creator:: Do, Hieu Trung
Abstract:: Translation surfaces can be viewed as polygons with parallel and equal sides identified. An affine homeomorphism φ from a translation surface to itself is called pseudo-Anosov when its derivative is a constant matrix in SL₂(R) whose trace is larger than 2 in absolute value. In this setting, the eigendirections of...
Resource Type:: Dissertation

Bioeconomic Simulation Modeling of Fisheries : Three Essays

Creator:: Cusack, Christopher Inju
Abstract:: Researchers rely on bioeconomic models to guide research and generate fishery management advice for commercial fisheries. Due partly to a paradigm shift towards ecosystem based fishery management, increasing complexity in the characteristics of the problems has meant that bioeconomic simulation models are becoming more prevalent in the fisheries literature. However...
Resource Type:: Dissertation

The Analysis of Hormone-dependent Transcription Factors and lncRNAs in Seeds by RNA Sequencing

Creator:: Sall, Khadidiatou
Abstract:: Seed dormancy is defined as the inability of viable seeds to germinate under conditionsotherwise favorable for germination. Dormancy provides a strategy for seeds to germinateat an appropriate time. Abscisic acid (ABA) is a major hormone involved in the regulationof seed dormancy. To elucidate the molecular mechanisms of dormancy, the twoexperimental...
Resource Type:: Dissertation

Dynamic Error Calibration for Continuous-Time Delta-Sigma Modulator with Multi-GHz Sampling Rate

Creator:: He, Tao
Abstract:: Continuous-time ΔΣ modulators are widely used in cellular handsets due to their power efficiency and inherent anti-aliasing characteristics. To achieve demanding cellular bandwidth requirements while maintaining good power efficiency, multi-bit feedback is typically used. This approach provides benefits such as lower OSR, relaxed loop filter requirements, and reduced jitter sensitivity....
Resource Type:: Dissertation

Power Efficient Architectures for Medium-high Resolution Analog-to-Digital Converters

Creator:: Sadollahi, Mahmoud
Abstract:: Analog-to-digital converters are essential components to the portable devices that we are using today. Wireless sensors, body implanted devices, communication devices and so forth require low power ADCs. Therefore achieving higher resolution and bandwidth with lower power consumption is targeted in ADCs design. In this work power efficient ADCs for...
Resource Type:: Dissertation

Advances in Modeling Natural Resource Management under Uncertainty : Forest Mortality, Policy Design, and the Value of Information

Creator:: Sloggy, Matthew R.
Abstract:: Advancing the understanding of natural resource management is an important step in mitigating the effects of human activity on the environment, and ensuring efficient outcomes for many sectors of the economy. As humanity’s role in the natural world becomes better understood, the importance of interdisciplinary modeling has grown in leaps...
Resource Type:: Dissertation

Dynamic and Dual Streaming Methods for H.264 Video and Parallel Performance Modeling

Creator:: Johnson, Taylor N.
Abstract:: Traditional approaches to streaming H.264 video over a network typically rely on a single method of transport (i.e., reliable or unreliable) and/or use static values for parameters that can have a significant negative impact on the perceptual quality of the received video. This dissertation presents a dynamic method for wireless...
Resource Type:: Dissertation

Co-channel Blocker and Self-Interferer Tolerant Receiver Architectures for MIMO and Full-Duplex MIMO Receivers

Creator:: Jain, Sanket
Abstract:: This research focuses on receiver architectures which enable better spectral eciency by handling blockers in the same spectral range as the signal. The presence of such blockers, without the use of blocker cancelling/ltering techniques leads to gain compression and hence, consequent performance degradation of receivers leading to reduced spectrum...
Resource Type:: Dissertation

Adaptive Streaming Methods using Dual Protocols and Reinforcement Learning

Creator:: Gatimu, Kevin
Abstract:: The ubiquity of high quality video and proliferation of mobile devices has contributed to an unprecedented rise in video consumption. HTTP, in conjunction with adaptive streaming, has become the de facto mechanism for delivering the vast majority of video as it readily caters to heterogeneous networks and devices. This dissertation...
Resource Type:: Dissertation

Identifiability-Aware Joint Sparse Error Correction For Robust State Estimation

Creator:: Kibria, Sharmin
Abstract:: We study joint nonlinear state estimation with multi-period measurement vectors that are potentially corrupted by sparse gross errors. The identifiability-aware approach is proposed to leverage common characteristics of fundamentally identifiable gross errors to enhance error correction performance. First, we derive a necessary rank condition that the sparsity pattern of any...
Resource Type:: Dissertation

Architecture Optimizations for Memory Systems of Throughput Processors

Creator:: Gu, Yongbin
Abstract:: Throughput-oriented processors, such as graphics processing units (GPUs), have been increasingly used to accelerate general purpose computing, including machine learning models that are being utilized in numerous disciplines. Thousands of concurrently running threads in a GPU demand a highly efficient memory subsystem for data supply in GPUs. In this dissertation,...
Resource Type:: Dissertation

Deletions and Insertions of the Symbol 0 and Asymmetric/Unidirectional Error Control Codes for the L₁ Metric

Creator:: Alqwaifly, Nawaf
Abstract:: This work gives some theory and efficient design of binary block codes capable of controlling the deletions of the symbol “0” (referred to as 0-deletions) and/or the insertions of the symbol “0” (referred to as 0-insertions). This problem of controlling 0-deletions and/or 0-insertions (referred to as symmetric 0-errors) is shown...
Resource Type:: Dissertation

Predicting and Improving Throughput, Responsiveness and Battery Life of Computer Systems by Machine Learning

Creator:: Li, Yunfan
Abstract:: The Machine Learning (ML) algorithms are increasingly explored in varies of fields including designing and optimizing computer systems. Recent research, such as optimizing memory/cache prefetching by ML training or predicting traffic pattern in throughput processors, also exhibits a promising future of introducing ML into computer system design and optimization. Throughput...
Resource Type:: Dissertation

A Rapid β-/γ Autoradiographic Imaging Method for Post-detonation Nuclear Forensics and Radiological Emergency Response

Creator:: Foley, Ari A. R.
Abstract:: In a radiological emergency scenario, the capability to rapidly visualize radiation emitted from debris, contamination, or absorbed in biological samples, while visualizing the non-radioactive (or “conventional” image) features within a ﬁeld of view, will provide critical information to support optimization of further analysis, sample collection, and decision making. This research...
Resource Type:: Dissertation

Convergence Analysis Framework for Fixed-Point Algorithms in Machine Learning and Signal Processing

Creator:: Vu, Trung
Abstract:: Iterative algorithms are simple yet efficient in solving large-scale optimization problems in practice. With a surge in the amount of data in past decades, these methods have become increasingly important in many application areas including matrix/tensor recovery, deep learning, data mining, and reinforcement learning. To optimize or improve iterative algorithms,...
Resource Type:: Dissertation

An inner product on adelic measures

Creator:: Oberly, Peter J.
Abstract:: We define an inner product on a vector space of adelic measures over a number field $K$. We find that the norm induced by this inner product governs weak convergence at each place of $K$. The canonical adelic measure associated to a rational map is in this vector space, and...
Resource Type:: Dissertation

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