Engineering Commons^™

Hydrodynamic Effects Of A Cannula In A Usp Dissolution Testing Apparatus 2, Qianqian Liu

Theses

Dissolution testing is routinely used in the pharmaceutical industry to provide in vitro drug release information for drug development and quality control purposes. The USP Testing Apparatus 2 is the most common dissolution testing system for solid dosage forms. Usually, sampling cannulas are used to take samples manually from the dissolution medium. However, the inserted cannula can alter the normal fluid flow within the vessel and produce different dissolution testing results.

The hydrodynamic effects introduced by a permanently inserted cannula in a USP Dissolution Testing Apparatus 2 were evaluated by two approaches. Firstly, the dissolution tests were conducted with two …

Research On Mppt Methods For Photovoltaic System Based On Microgrid, Jingchu Ji

Theses

This thesis introduces some basic concepts about a microgrid. Then it discusses the structure of photovoltaic system (PVS) which contains a solar panel and simplified PV models. Next, it discusses and compares different methods for Maximum Power Point Tracking (MPPT) with PVS. It presents three types of DC-DC converters -- Buck, Boost and Buck-Boost converter. This work proposes to apply a DC-DC converter of Buck-Boost type to make PVS controllable because this type of converter has the largest range for operational region so that it can get the best result on MPPT. Finally, this thesis presents a kind of new …

Effects Of Api Particle Size On The Dissolution Rate In Molten Polymer Excipient Matrices During Hot Melt Extrusion, Conducted In A Co-Rotating Twin-Screw Extruder, Meng Li

Theses

The effect of the Active Pharmaceutical Ingredient (API) particle size on the dissolution rate in the polymer excipient during hot melt extrusion is investigated using a co-rotating twin-screw extruder with three different screw configurations. Acetaminophen (APAP) and amphiphilic polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (PVCap-PVAc-PEG) (Soluplus) are chosen as the model API and water- soluble polymer excipient, respectively. APAP is milled using a fluid energy mill (FEM) into two different particle sizes. The thermal properties of processed samples are characterized by TGA and DSC. SEM and optical microscopy are also used in the morphological studies. Under quiescent conditions, API particles …

Engineering Spores To Display G Protein-Coupled Receptors For Directed Evolution, Alyssa Misoo Kim

Theses

All human cells are surrounded by a plasma membrane made from a phospholipid bilayer, which is responsible for maintaining a biologically active species, while stopping entry of deleterious substances from the outside. G protein-coupled receptors (GPCRs) are the membrane proteins, which transmit signals across the cell membrane. GPCRs are involved in almost every physiological process, and irregular control leads to pathological conditions. Therefore, they are major drug targets. Crystal structure determination is required to understand the molecular details of activation/deactivation. However, GPCRs are difficult to crystallize because of stability issues. An efficient protein engineering system needs to be developed. The …

Admittance Control Of The Intelligent Assist Robot Manipulator For People With Duchenne Muscular Dystrophy, Madeline Corrigan

Theses

Duchenne muscular dystrophy (DMD), a neuromuscular disease with a prevalence of 1 in 3500 male births, results in characteristic muscle weakness which is progressive with age and leads to loss of independence. And, in this population, maintaining optimal quality of life depends on the preservation of self-sufficiency. Despite the loss of function, non-ambulant people with DMD retain some muscle strength, just not sufficient strength to overcome the force of gravity. There are a number of upper-limb passive and active orthotic devices that attempt to augment the loss of upper limb function in people with DMD by taking advantage of this …

Study Of Poly (L-Lactic Acid)/Poly (D-Lactic Acid) Stereocomplex As Nucleating Agent For Poly (L- Lactic Acid) Crystallization, Yuan Lao

Theses

Poly (lactic acid) (PLA) is a biodegradable polymer with good renewability and processability. However, it has some drawbacks. The Poly (lactic acid) (PLA) stereocomplex formed via the interaction between optical isomers Poly (L-lactic acid) (PLLA) and Poly (D-lactic acid) (PDLA), provides improvements on PLA thermomechanical properties. To investigate the nucleating effect brought by the PLA stereocomplex, samples of PLLA blended with different content of PDLA are prepared by the solution casting method. With different cooling rates (5, 15, 25 °C/min), DSC non-isothermal crystallization experiments are performed. The results suggest that in the presence of the stereocomplex, the PLLA crystallization temperatures …

Role Of Materials & Design On Performance Of Baseball Bats, Kim Benson-Worth

Theses

Baseball bat safety has become an increasing area of interest with more than 19 million people in the United States alone participating in this sport. An increase in injuries resulting from bat injuries has brought the performance of the bats into question. A review of several studies focusing on the effects of the material properties of various baseball bats designs were examined. From this review it is evident that player and spectator safety greatly rely on proper baseball bat design. There was a 30% reduction in the Multi-Piece Failures (MPF) of wooden bats once the requirement of a Slope of …

Detection Of Video Frame Insertion Based On Constraint Of Human Visual Perception, Lu Zheng

Theses

Recently, due to availability of inexpensive and easily-operable multimedia tools, digital multimedia technology has experienced drastic advancements. At the same time, video forgery becomes much easier and makes more difficult to validate the video content. Consequently, the origin and integrity of video can no longer be taken for granted. A methodology is developed that is capable of detecting the video frame insertion based on the constraint of human visual perception. The main idea is based on the so-called differential sensitivity. That is, that the variation of brightness of neighboring video frames has some constraint. First, the video sequence is partitioned …

Qsar Modeling Of Chemical Penetration Enhancers Using Novel Replacement Algorithms, Hui Qiu

Theses

The applications of transdermal delivery are limited because of the resistance of the skin to drug diffusion. Only potent drugs, with molecular weight less than 500 Da, are suitable to cross the skin barrier. Chemical Penetration Enhancers (CPEs) are used to promote the absorption of solutes across the dermal layers. In this investigation, a Quantitative Structure-Activity Relationship (QSAR) model is applied to relate chemical penetration enhancer structures with the flux enhancement ratio through a statistical approach.

A database, consisting of 61 non-polar CPEs, is selected for the study. Each compound is represented by 777 QSAR descriptors, which encode the physical …

Effect Of Tablet Compression On The Dissolution Of Aspirin Tablets Using A Novel Off-Center Paddle Impeller (Opi) Dissolution Testing System, Chuan Sun

Theses

In the pharmaceutical industry, dissolution testing is routinely carried out to determine the dissolution rate of oral solid dosage forms. Among several testing devices, the USP Dissolution Apparatus 2 is the device most commonly used. However, despite its widespread use, this apparatus has been shown to produce test failures and to be very sensitive to a number of small geometry changes.

The objective of this study was to determine whether a novel dissolution system termed “OPI” for “off-center paddle impeller” was sensitive enough to determine differences in tablet dissolution profiles caused by different compression pressure during the tablet manufacturing process. …

Dissolution Of Different Commercial Aspirin Tablets Using A Novel Off-Center Paddle Impeller (Opi) Dissolution Testing System, Yang Qu

Theses

Dissolution testing is routinely conducted in the pharmaceutical industry to provide in vitro drug release information for quality control purposes. The most common dissolution testing system for solid dosage forms is the United States Pharmacopeia (USP) Dissolution Testing Apparatus 2. In this work, a modified Apparatus 2, termed "OPI" System for "off-center paddle impeller," in which the impeller is placed 8 mm off center in the vessel is tested to determine its sensitivity to differentiate between the dissolution profiles of differently formulated and manufactured tablets. Dissolution tests are conducted with both the OPI System and the Standard System using three …

Current Measurements In Electrospinning, Clinton K. Lien

Theses

Electrospinning provides an economical method of producing nanofibers. The current carried by the main spinning jet is found to be one of the factors in determining the diameter of the fiber product. However, current sources such as the corona discharge and secondary jets will lead to a systematic overestimation of the actual current value.

In this research, experiments with different configurations are set up to investigate the influence of various parameters on the measured current. It is noticed that the measured current is nearly independent on the flow rate of the solution and the external cover. A large amount of …

Nanocluster Production For Solar Cell Applications, Haila M Aldosari

Theses

No abstract provided.

Quantification Of Human Motion On Roller Coaster Rides, Chirag Burman

Theses

Case reports have been published of people experiencing symptoms of traumatic brain injury (TBI) and/or ailments of the vascular tissue around the head. These reports pointed towards G-forces, a scalar measure without a specified direction, which represent the measure of the acceleration of an object divided by acceleration caused by gravity (9.81 m/s²), as a cause of said injuries. Research has been conducted on quantifying the G-forces experienced while on roller coasters, as well as the change in heart rate. However these studies have not been able to show a link between roller-coasters and symptoms.

This thesis aims …

Safety Performance Comparison Between Light Rail Transit And Subway, Nehemie Jasmin

Theses

Along with the expansion and addition of guide way transit systems, such as light rail and subway, there came the need to compare the safety performance of each mode. The multimodal transportation systems with many different technologies, operating characteristics and diversified environments made it more difficult to compare their safety.

In order to evaluate the potential for intermodal comparison of safety performance measures, the thesis has focused on the subway and Light Rail Transit (LRT) modes at the national level. Starting with clear definitions of each safety category, the analysis utilizes mostly the National Transit Database (NTD) from recent years …

Fuzzy Logic For Task Space Telemanipulation Of A Five Fingered Robotic Hand, Raaghavann Srinivasan

Theses

This work presents a fuzzy logic based HandyMan (Hand gesture commands for grasping and manipulation) system to recognize the operator's hand gestures during task space telemanipulation. A combination of joint positions may be shared between at least two manipulation gestures. To avoid misinterpretation of gestures by the gesture recognition system, six new manipulation gestures were introduced. The gestures are produced by the user wearing a CyberGlove™.

This system replaces the previous HandyMan gesture recognition method. The output of the fuzzy system drives the state machines to implement the gestures with the robot hand.

The experimental results show that the proposed …

Diffuse Axonal Injury Effect On Myelinating Cells And Axons, Jennifer Alison Zalk

Theses

There is no supporting evidence whether myelin degeneration in diffuse axonal injury (DAI) of the white matter is due to death of myelinating oligodendrocytes or secondary axotomy. Cortical neurons are not able to remain healthy in culture to have their axons myelinated. Dorsal root ganglion (DRG) neurons have been shown to be myelinated by cortical oligodendrocytes in culture. An in vitro stretch injury model was used to analyze the DRG axon pathology during and after injury. DRG myelinating Schwann cells are analyzed to demonstrate what is expected from injury to oligodendrocytes. DRG axons demonstrated a high tolerance to stretch …

Examination Of Thermal Properties Of Carbon-Carbon And Graphitized Carbon-Carbon Composites, Melanie Jene' Patrick

Theses

Thermal characterization of composites is essential for their proper assignment to a specific application. Specific heat, thermal diffusivity, and thermal conductivity of carbon-carbon composites are essential in the engineering design process and in the analysis of aerospace vehicles, space systems and other high temperature thermal systems. Specifically, thermal conductivity determines the working temperature levels of a material and is influential in its performance in high temperature applications. There is insufficient thermal property data for carbon-carbon composites over a range of temperatures. The purpose of this research is to develop a thermal properties database for carbon-carbon composites that will contain in-plane …

Thermal Characterization Of As4/3501-6 Carbon-Epoxy Composite, Bradley R. Doleman

Theses

Thermal diffusivity, specific heat, and thermal conductivity are important thermophysical properties of composite materials and foams. Thermal characterization provides these material properties which play a significant role in the engineering design process of space systems, aerospace vehicles, transportation, energy storage devices, and power generation including fuel cells. Thermal conductivity is the parameter that is important in problems involving heat transfer and thermal structures. Because it determines the working temperature levels of a material, the thermal conductivity is critical when considering the performance of materials in high temperature applications as well as safety, process control, and quality assurance. As a result …

The Behaviour Of Connections In Segmental Precast Concrete Pile Systems, Evan Causer

Theses

Driven precast concrete segmental piles are a popular foundation solution. Segmental pile systems incorporate connections into the pile, therefore it is important to be confident that the strength of the pile joints is comparable to that of the pile cross-section.

The primary objective of the research was to examine the behaviour of connections in segmental precast concrete pile systems. This was achieved by undertaking a literature review, laboratory testing and Finite Element Analysis (FEA).

The uses of segmental concrete pile systems are described and a review of the available pile joints is given. A review of the relevant design codes …

An Investigation Of Transverse Load Distribution In Masonry Arch Bridges, Helen Dunne

Theses

Masonry arch bridges comprise a significant proportion of the bridge stock both nationally and internationally. They have proven to be enduring structures, far surpassing their design lives and with relatively low life-cycle costs, are environmentally friendly (Sustainable Bridges, 2007).

New masonry arch bridges are not generally constructed. However, their ageing materials paired with ever increasing traffic loads have led to the necessity for their periodic re-assessment. Masonry arch bridge design was predominantly by rule of thumb and their re-assessment has been subject to a number of simplified assumptions. One such simplification, the bridge “effective width” is studied in this thesis. …

An Investigation Into The Potential Of Increasing The Span Of Solid Slab Deck Bridges, Eamonn Kiernan

Theses

Solid slab deck bridges are a common type of structure employed for short to medium span bridges. They may be of rapid build nature if they are made up of prestressed precast sections with concrete infill deck.

The aim of this research was to investigate the potential to increase the span of solid slab deck bridges by the employment of high strength concrete (HSC), lightweight aggregate concrete (LWAC) and the use of a voided deck.

The analysis undertaken in the research was based on a bridge, which was recently constructed in Cork; the bridge was constructed using MY beam sections, …

Structural Behaviour Of Semi-Continuous Steel End Plate Connections, Niall Scollard

Theses

This report focuses on determining the joint stiffness and moment capacity values for semi-continuous (semi-rigid) connections in steel framed structures. When designing a beam to column connection, the assumption that the Joint is either fully continuous or fully pinned may not be entirely valid; it may be more realistic to classify the connection as intermediate between fully pinned and fully continuous.

The development of “the component method”, which is utilised in IS EN 1993-1-8 (EC3) to determine design values of the joint properties is described. A software solution was created using Microsoft Excel to carry out calculations in accordance with …

Investigation Into The Measure, Correlate And Predict Methodologies Used In Wind Farm Design Software, Brendan O'Sullivan

Theses

This paper is focused on the Measure Correlate and Predict (MCP) methodologies used to estimate long term wind resource at a prospective site. The first common step in all MCP methodologies is a successful wind measurement campaign at the prospective site. This campaign involves the erection of a wind measurement mast (ideally to the hub height of the proposed turbine) and careful selection of booms, mountings and anemometers. The wind measurement campaign is a vital part of the process as the correlation and prediction analysis is only as accurate as the measured wind data. Correlation is a measure of the …

Non-Uniform Transmission Lines For Ultra Wideband: Design Optimisation And Interfacing To Antennas And Loads, Prasanth Moolakuzhy Narayanan

Theses

This thesis presents the electrical characterization of ultra-wideband non- uniform transmission lines (UWB NUTLs). Non-uniform transmission lines have been identified as a successful device for ultra-wideband pulse shaping, which can be designed to generate complex and arbitrary pulse shapes as an impulse response. The performance of a range of UWB NUTLs, with different substrate materials and load impedances, has been characterised. In addition, the possibility of interfacing NUTL with antennas and the filtering effect of antennas has been investigated. To characterise the NUTLs, knowledge of current literature related to NUTL designs is required. A detailed review of the literature published …

Modelling Of Bed Load Transport In The River Bandon, Stephen Falvey

Theses

This research thesis examines the various aspects of fluvial sediment transport with a particular emphasis on bed load transport. Sediment is a dynamic, essential and important part of Ireland’s river basins. The collection of sediment transport data is very important as it can help prevent flooding, improve water quality, protect ecology and assist cities and towns in future planning. At the moment there is no legislation dedicated exclusively to sediment but it does interface with a range of other pieces of legislation including the Water Framework Directive.

This literature review studies sediment transport. There is a particular emphasis on the …

Classification Of Irish Beaches To Determine Their Potential For Erosion, Aidan O'Connell

Theses

The objective of this literature review is to gather the relevant information regarding beach characteristics and beach erosion in order to undertake the project development stage of the thesis project. The background information that was reviewed was the different zones that are located on a beach; the functions of a beach and what most beaches are commonly used for; how beaches were formed; the legislation that is related to the beach or any work that is required to be carried out on a beach and some background information on the erosion of beaches.

The most relevant beach characteristics that impact …

Carbon Dioxide Absorption And Channelling In Closed Circuit Rebreather Scrubbers, Shona Cunningham

Theses

Closed Circuit Rebreathers (CCRs) are a type of Self Contained Underwater Breathing Apparatus (SCUBA) used predominantly by the diving community. CCR technologies have become prevalent within the commercial, military and technical diving communities over recent years. CCRs work by recycling breathing gas, by-passing the gas through a carbon dioxide (CO₂) chemical scrubber and topping the resultant scrubbed gas up with pure oxygen to maintain the oxygen content at a level which supports life. One of the main dangers currently faced by divers using this equipment is the risk of CO₂ poisoning if the scrubber fails. This failure …

The Potential For The Elimination Of Expansion Joints And Bridge Bearings From Existing Road Bridges In Ireland, Conor Keena

Theses

This research was focused on determining the feasibility of eliminating expansion joints and bridge bearings from existing short to medium span road bridges in Ireland. It is possible that this could provide a significant long-term economic benefit to bridge owners. A literature review was carried out as part of the research. This included investigations into research conducted in the areas of thermal movements of bridges, concrete creep and shrinkage, soil-structure interaction, lifetime costing, design standards and finite element analysis, and the elimination of bridge expansion joints in other countries.

Finite element analyses were carried out on two existing road bridges. …

The Design Of Moment Connections Between Rectangular Hollow Sections, Billy Allen

Theses

Steel portal frames in the construction industry typically comprise 1 and H sections. The design procedures for the connections in these frames (base, eaves and apex) are well established. This research is based on using rectangular hollow sections as the column and rafter members.

The eaves connection of a rectangular hollow section pitched portal frame is investigated in this report and includes a literature review of various experimental research relating to moment connections between rectangular hollow sections.

Three eaves joints were considered in this research. The joints were physically tested in the laboratory and a finite element analysis carried out. …