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Full-Text Articles in Engineering

A Haptic Control System For Functional Electrical Stimulation Of Paraplegic Legs, Mark R. Shaker Aug 2010

A Haptic Control System For Functional Electrical Stimulation Of Paraplegic Legs, Mark R. Shaker

Theses

Functional electrical stimulation (FES) is a means by which paraplegic men and women can use their natural legs for walking. In FES the impaired muscles are stimulated with electricity in a proper cycle to cause the legs to move in a walking pattern. It can be greatly beneficial for paraplegics however, current systems are not widely used because they are difficult to control in a useful manner.

The system proposed here uses a haptic interface, one that utilizes the sense of touch, attached to a user’s index and middle fingers. The haptic device allows the wearer to feel with the …


Motor Data Scaling By Respiration Frequencies In Rest, Amit Madhukar Kamble Aug 2010

Motor Data Scaling By Respiration Frequencies In Rest, Amit Madhukar Kamble

Theses

Functional Magnetic Resonance Imaging (fMRI) is widely used as a tool to see activations in the different brain regions. Motor data acquired from fMRI scan is accompanied with signal due to hemodynamic changes taking place during the scan. This hemodynamic signal is dominated by parameter alteration in the large vessels of brain. Scaling of task induced BOLD signal with hypercapnic or breathold data is one of the effective methods to minimize the signal due to large vessels. Patient discomfort and compliance has been a major issue with these methods hence in this study we used respiration frequencies in rest data …


Axon Guided Axon Growth In Drg Neurons From The Spinal Cord Of Rat Embryos, Neha Jain May 2010

Axon Guided Axon Growth In Drg Neurons From The Spinal Cord Of Rat Embryos, Neha Jain

Theses

Early studies in the area of neuronal physiology and injury have shown that axons are guided by a number of physical as well as chemical cues. Although the guidance effect of initial axons and their processes on later axons has been shown from a development point of view, little light has been thrown on the subject from the injury point of view. This important ability of axons which plays a key role during development and formation of neuronal networks could become crucial in repairing damaged nerves and disrupted neuronal tracts.

In the following study, the guidance effect of an older …


Design Of Drug Delivery Strategies Based On Well-Stirred Experiments, Kumud Kanneganti May 2010

Design Of Drug Delivery Strategies Based On Well-Stirred Experiments, Kumud Kanneganti

Theses

Drugs are generally administered to the human body via injections (IV) or through other paths such as the buccal, nasal routes. The main consideration when designing a medication schedule is to maintain a therapeutic level of the drug in the body during the course of treatment. To achieve this goal, when IV drug therapy is selected, particular importance has to given to the dose to be injected and how to maintain the concentration of the pharmaceutical active ingredient (API) in the body between a Minimum Toxic Concentration (MTC) and a Minimum Effective Concentration (MEC). This therapeutic range varies with the …


A Study Of Probability Distributions Of Dct Coefficients In Jpeg Compression, Gopal Thirumalai Narayanan May 2010

A Study Of Probability Distributions Of Dct Coefficients In Jpeg Compression, Gopal Thirumalai Narayanan

Theses

The Discrete Cosine Transform (DCT) used in JPEG compression has shown excellent energy compaction properties that rival that of the ideal Karhunen-Loève Transform. Lossy compression in JPEG is achieved by distorting 8x8 block DCT coefficients through quantization. It has been shown in literature that DC block DCT coefficients are Gaussian probability distributed and AC block DCT coefficients are Generalized Normal probability distributed.

In this investigation, three probability density models for individual modes of non- quantized AC block DCT coefficients are evaluated and are used as basis for the derivation of probability distributions for quantized block DCT coefficients. The suitability of …


Exploiting The Concept Of Hysteresis In Ankle Dysfunction And Ankle Strengthening, Akshay Narendra Pujara May 2010

Exploiting The Concept Of Hysteresis In Ankle Dysfunction And Ankle Strengthening, Akshay Narendra Pujara

Theses

The ankle joint is an important part of the body which is responsible for normal gait cycle. Dorsiflexion, plantar flexion, inversion and eversion are four types of movements controlled by the ankle joint. All these movements are controlled by the ligaments and the muscles associated with the ankle. Disorders of these ligaments and muscles leads to ankle dysfunction.

The hysteresis concept was employed to determine if there is any ankle dysfunction. A recently developed device, the Ankle Torsion Monitor (AnTm) was employed to evaluate the viscoelasticity and stiffness of the ankle joint. The greater the hysteresis loop area (HLA) the …


Air Piston Approach To Wave Power Generation, Arun Ramadass May 2010

Air Piston Approach To Wave Power Generation, Arun Ramadass

Theses

Scientists have calculated that, by tapping just 0.2% of the energy produced by the world's oceans we can provide for all the worlds current energy needs. It is generally accepted that a combination of traditional energy production methods, (oil, coal, gas, nuclear) mixed with a combination of renewable energy production approaches is the future in providing for an increasingly energy hungry world. Wind, solar and biomass have moved into the public arena only in the last few years.

The proposed patented device (US Patent No.: 7,468,563) Ocean Wave Energy Converter harnesses the energy of ocean waves by continually raising and …


Papr Reduction In Ofdm Communications With Generalized Discrete Fourier Transform, Sertac Sayin May 2010

Papr Reduction In Ofdm Communications With Generalized Discrete Fourier Transform, Sertac Sayin

Theses

The main advantage of Generalized Discrete Fourier Transform (GDFT) is its ability to design a wide selection of constant modulus orthogonal code sets, based on the desired performance metrics mimicking the engineering specs of interest. One of the main drawbacks of Orthogonal Frequency Division Multiplexing (OFDM) systems is the high Peak to Average Power Ratio (PAPR) value which is directly related to power consumption of the system. Discrete Fourier Transform (DFT) spread OFDM technology, also known as Single Carrier Frequency Division Multiple Access (SCFDMA), which has a lower PAPR value, is used for uplink channel.

In this thesis, the PAPR …


Comparison Between Different Techniques Of Preprocessing For Resting State Fmri Analysis, Megha Girdhar May 2010

Comparison Between Different Techniques Of Preprocessing For Resting State Fmri Analysis, Megha Girdhar

Theses

Resting state functional connectivity as the name suggests is defined as significant temporal correlation between spatially distinct regions of the brain during rest. In this thesis, fMRI resting state dataset was analyzed using different available processing techniques with the same fMRI data to study differences between the various methods. All the imaging data from each of the subjects was processed in an identical fashion. The same method was used for detecting connectivity. The number of independent components in the data was used as the base to differentiate the effect of each of these methods. Independent component analysis was performed on …


Interfacially Polymerized Thin Film Composite Membranes On Microporous Polypropylene Supports For Reverse Osmosis Desalination, Chao Li May 2010

Interfacially Polymerized Thin Film Composite Membranes On Microporous Polypropylene Supports For Reverse Osmosis Desalination, Chao Li

Theses

The important technique of interfacial polymerization (IP) is used to fabricate thin film composite (TFC) membranes. In experiments here, microporous polypropylene (PP) flat film membranes were used as a support for fabricating TFC membranes for reverse osmosis by the IP technique. Substantial chemical, pH, and solvent resistance is provided by porous polypropylene membranes. Therefore, it is reasonable to choose porous polypropylene membranes as supports to fabricate TFC membranes for reverse osmosis.

The external and the pore surfaces of polypropylene flat film membrane were hydrophilized first by pre-wetting with acetone, then oxidized with chromic acid solution kept at 65°C. Next, the …


Stochastic And Deterministic Dynamics Investigation Of The Microstructure Of Granular Materials, Vishagan Ratnaswamy May 2010

Stochastic And Deterministic Dynamics Investigation Of The Microstructure Of Granular Materials, Vishagan Ratnaswamy

Theses

Granular materials are ubiquitous in one's daily life. They can be found in the cereal you eat, the sugar you put in your coffee or the sand you walk on in the beach. The study of granular materials has a rich history dating back to the 17th century where Kepler studied the packing of particles. The compaction of granular materials is a problem that is studied by using theory, experiments and simulations. While these studies have yielded some important results, there still are many details about the mechanisms of granular compaction that are unknown.

In this thesis, the density relaxation …


Automation Of Anatomic Torsion Monitor For Evaluation And Improvement Of Low Back Dysfunction, Vishal Kumar Singh May 2010

Automation Of Anatomic Torsion Monitor For Evaluation And Improvement Of Low Back Dysfunction, Vishal Kumar Singh

Theses

The existing Anatomical Torsion Monitor (ATM) to evaluate mechanical stiffness and viscoelasticity of the low back suffers from various inherent defects. This has to be replaced by an improved device. Also the existing ATM cannot provide oscillations to the low back.

The main objective is to automate the existing ATM for evaluating the low back immediately using objective methods. The specific objective is to provide oscillations for improving the low back dysfunction.

The laser platform and the target chart for recording the readings are dispensed with the existing ATM. Instead, the ultrasound transducers are attached to the pads to record …


A Comparison Of Software Engines For Simulation Of Closed-Loop Control Systems, Sanket D. Nikam May 2010

A Comparison Of Software Engines For Simulation Of Closed-Loop Control Systems, Sanket D. Nikam

Theses

A wide array of control system design and simulation software engines is available in market. It includes MATLAB-Simulink, LabVIEW, Maple-MapleSim, Scilab-Scicos, VisSim and Mathematica-Control Professional Suite (CPS). Among all of them MATLAB-Simulink is dominant and widely used software engine. The main aim of this study is to implement different state space control methods for non-linear Furuta pendulum system in each one of them and to compare performance against MATLAB-Simulink.

Different parameters like learning curve, interoperability, flexibility, control design tools, documentation and tech support are considered for efficiency comparison. It is shown that MapleSim has multi-body intuitive physical modeling (acausal) approach …


Power Flow In Railway Electrification Power System, Sisi Li May 2010

Power Flow In Railway Electrification Power System, Sisi Li

Theses

This thesis discusses aspects of the design of the railway electrification system (RES) and in particular the electric distribution system for a 2x25 kV railway power system.

The analysis of Railway Power Supplies (RPS) presents a unique type of load flow problem which is characterized by its constant moving loads, dynamically changing load types (constant current/constant power), and its specialized network structure. The autotransformer power supply system with double track was the system studied in this thesis.

The details of the system studied were provided by Caltrain (California Commuter Rail) for a planned high speed extension to Caltrain system. A …


Study Of Methods To Predict Voltage Collapse, Niki Patel May 2010

Study Of Methods To Predict Voltage Collapse, Niki Patel

Theses

One of the problems that must be addressed for a secure power system operation is the voltage collapse problem. The ever increasing size and connectivity of the power grid have lead to making the problem more multifarious. Widespread blackouts, similar to the one that occurred in the northeast in August 2003, could result from failure to address the problem.

This thesis presents an overview of the voltage collapse problem and reviews some existing methods to calculate voltage collapse indicators.

Thevenin and Maximum Power Transfer Theorems are used to provide indicators of the proximity of the system to voltage collapse. The …


Minimum Agitation Speed For Solid Suspension And Mixing Time In A Torispherical -Bottomed Pharmaceutical Stirred Tank Under Different Baffling Conditions, Dilanji Bhagya Wijayasekara May 2010

Minimum Agitation Speed For Solid Suspension And Mixing Time In A Torispherical -Bottomed Pharmaceutical Stirred Tank Under Different Baffling Conditions, Dilanji Bhagya Wijayasekara

Theses

The minimum agitation speed, NS, required to just suspend solid particles dispersed in water was experimentally determined in this work for a glass-lined type of mixing tank provided with a torispherical bottom and agitated with a retreat-blade impeller under different baffling configurations. Ns for the same tank but equipped with a different agitation system, namely an axial impeller, was also experimentally determined for the purpose of comparing of performances of the two systems. The effect of impeller off- bottom clearance and the vessel's liquid level on the minimum agitation speed were also experimentally studied. Njs, was experimentally determined …


A Fpga/Dsp Based Ultrasound System For Tumor Detection, Ashish Ravindra Ratnakar May 2010

A Fpga/Dsp Based Ultrasound System For Tumor Detection, Ashish Ravindra Ratnakar

Theses

This work presents a method of detection of size and location of tumor using ultrasound transmission. The system utilizes Quantitative Ultrasound (QUS) which means sending an ultrasound signal from a transmitter and receiving it at multiple receivers. This received signal is analyzed for echogenic as well as echolucent tumors to differentiate between the two along with non-tumorous sample and also for delay, signal distortion to determine the size/location of the tumor.

This analysis is further implemented using Field Programmable Gate Array (FPGA) and Digital Signal Processor (DSP) technologies. The proposed detection system utilizes Low Transient Pulse (LTP) technique. In this …


Stiffness Of Vascular Smooth Muscle Cells From Aged Primates Measured Using Reconstituted Tissue Model, Shilpa Nagendra Jan 2010

Stiffness Of Vascular Smooth Muscle Cells From Aged Primates Measured Using Reconstituted Tissue Model, Shilpa Nagendra

Theses

Increased stiffness of the aorta is an important detrimental change that occurs with aging. Most previous research has implicated stiffening of the extracellular collagen matrix with age. The study reported in this thesis focused instead on the potential contribution from stiffening of the vascular smooth muscle cells (VSMCs) with age.

VSMCs previously obtained from young and old monkeys (macaca fascicularis) were seeded into a collagen gel to form a reconstituted tissue. The aim of this study was to quantitatively characterize the mechanical properties of this reconstituted tissue model via uniaxially stretching each ring to defined levels of strain. The total …


A Fpga/Dsp Design For Real-Time Fracture Detection Using Low Transient Pulse, Akash Mathur Jan 2010

A Fpga/Dsp Design For Real-Time Fracture Detection Using Low Transient Pulse, Akash Mathur

Theses

This work presents the hardware and software architecture for the detection of fractures and edges in materials. While the detection method is based on the novel concept of Low Transient Pulse (LTP), the overall system implementation is based on two digital microelectronics technologies widely used for signal processing: Digital Signal Processor (DSP) and Field Programmable Gate Array (FPGA). Under the proposed architecture, the DSP carries out the analysis of the received baseband signal at a lower rate and hence can be used for large number of signal channels. The FPGA's master clock runs at a higher frequency (62.5MHz) for the …


Sparse Representation For Audio Noise Removal Using Zero-Zone Quantizers, Neha Mittal Jan 2010

Sparse Representation For Audio Noise Removal Using Zero-Zone Quantizers, Neha Mittal

Theses

In zero zone quantization, bins around zero are quantized to a zero value. This kind of quantization can be applied on orthogonal transforms to remove the unwanted or redundant signal. Transforms reveal structures and properties of a signal and hence careful application of a zero zone over the transform coefficients leads to noise removal. In this thesis, such quantizers are applied over Discrete Fourier Transform and Karhunen Loeve Transform coefficients separately, and outputs compared. Further, the localization of the zero zones to certain frequencies leads to better performance in terms of noise removal. PEAQ (Perceptual Evaluation of Audio Quality) scores …


A Comparative Analysis Of Haptic And Eeg Devices For Evaluation And Training Of Post-Stroke Patients Within A Virtual Environment, Gregory Nicholas Ranky Jan 2010

A Comparative Analysis Of Haptic And Eeg Devices For Evaluation And Training Of Post-Stroke Patients Within A Virtual Environment, Gregory Nicholas Ranky

Theses

Virtual Rehabilitation benefits from the usage of interfaces other than the mouse and keyboard, but also possess disadvantages: haptic peripherals can utilize the subject's hand to provide position information or joint angles, and allow direct training for specific movements; but can also place unneeded strain on the limbs; brain-machine interfaces (BMI) can provide direct connections from the user to external hardware or software, but are currently inaccurate for the full diversity of user movements in daily life and require invasive surgery to implement. A compromise between these two extremes is a BMI that can be adapted to specific users, can …


Development Of A Device For Whole Body Stimulation Of The Otoliths, Jon Edward Weimer Jan 2010

Development Of A Device For Whole Body Stimulation Of The Otoliths, Jon Edward Weimer

Theses

Over the past few decades, research has been conducted to explore the effects of microgravity on human musculature, As seen in astronauts upon their return to Earth after prolonged spaceflight, extensive muscle atrophy due to adaptation to conditions of microgravity many times decreases a person's ability to walk or even stand, With an understanding of the anatomical mechanisms that provide postural control, the proper stimulation, resulting in a reduction in spasticity, could be provided by simulating these conditions of microgravity.

In order to simulate microgravity, a device has been developed that is capable of providing whole body stimulation of the …