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Full-Text Articles in Engineering

Investigating The Parameters That Influence The Particle Mass Concentration Rates In A Grade C Cleanroom., Nazar H. Baker Jan 2017

Investigating The Parameters That Influence The Particle Mass Concentration Rates In A Grade C Cleanroom., Nazar H. Baker

Theses

The cleanroom design engineers use the guidelines tables, in which the Air Change Rates (ACHs) are determined based on the room cleanliness class. These guidelines are based on experience and do not fully address many other critical variables that influence the particulate level and particle distribution. These simplified approaches could often cause significant energy waste. In the last five decades, a number of mathematical models were developed to determine the airflow required in cleanrooms. As a consequence of the approximation of many critical variables in these models, these models can only be used as a qualitative indicator of the airflow …


Development & Validation Of An Improved Biomechanical Model For Motion Analysis, Darren Dawson Jan 2017

Development & Validation Of An Improved Biomechanical Model For Motion Analysis, Darren Dawson

Theses

Three dimensional motion analysis systems are utilised across a number of different disciplines, including clinical gait analysis, sports performance studies and analysis of tasks of daily living. These systems utilise biomechanical models which define body segment coordinate systems and calculate kinematic and kinetic relationships about the joints between adjacent coordinate systems. In this study, a biomechanical model for general use in motion analysis was developed and validated. It was designed to improve upon the accuracy and capability of currently available models. The newly developed model utilises state of the art techniques to accurately define body segment coordinate systems. Accurate predictive …


Effect Of Temperature On The Fracture Behavior Of Lead-Free Solder Joints, Patrick Thompson May 2016

Effect Of Temperature On The Fracture Behavior Of Lead-Free Solder Joints, Patrick Thompson

Theses

The objective of the present study is to examine the effect of temperature on the fracture behavior of Cu-SAC305-Cu joints. To this end, double cantilever beam (DCB) specimens, consisting of a thin layer of Sn96.5Ag3.0Cu0.5 (SAC305) solder sandwiched between two copper bars, fabricated under standard surface mount (SMT) processing conditions are fractured under various temperatures with a MTS machine equipped with an environment chamber. The load-displacement behavior corresponding to crack initiation and the subsequent toughening before ultimate failure and the displacements near crack tip are recorded and used to calculate the fracture energy release rates. The fracture surfaces and the …


Numerical Analysis For The Hemodynamics In Unruptured Cerebral Aneurysms, Hashem Mhd Hicham Alargha Apr 2016

Numerical Analysis For The Hemodynamics In Unruptured Cerebral Aneurysms, Hashem Mhd Hicham Alargha

Theses

A cerebral aneurysm is a vascular disorder characterized by abnormal focal dilation of a brain artery which is considered as a serious and potentially life-threatening condition. Cerebral aneurysms affect around 2%-5% of adults and they are fatal and can rupture with an overall mortality rate of more than 50%. Through computational fluid dynamics investigation, this study is offering a closer look into the initiation growth and rupture of cerebral aneurysms. Four focus points are studied in this thesis which are sensitivity analysis of blood viscosity in aneurysms, the effect of cerebral aneurysm size on wall stresses and strain, hazard effects …


Shock Wave Interaction With A Fluid Filled Cylinder Experimental Methods, Praveen Kumar Baba Siddabattuni Jan 2016

Shock Wave Interaction With A Fluid Filled Cylinder Experimental Methods, Praveen Kumar Baba Siddabattuni

Theses

In the recent wars of Iraq and Afghanistan, many soldiers sustained bTBI (blast-induced traumatic brain injury). The blasts are created by extensive use of improvised explosive devices (IED’s). Whether pure blast-shock waves cause TBI or what is the mechanism of injury are not fully known. Research efforts are underway to find answers to these questions.

The primary objective of this project is to understand how the shockwave interacts with a fluid-filled cylinder of different thicknesses. Here, the cylinder is idealized as head and the fluid filled inside it as the brain material. The primary interest here is, how the pure …


Numerical Validation Of Cooling Performance Of Phase Change Materials Integrated Into Heat Sinks For Electronics Cooling, Shaimaa Mohamed Abu Ayyan Dec 2015

Numerical Validation Of Cooling Performance Of Phase Change Materials Integrated Into Heat Sinks For Electronics Cooling, Shaimaa Mohamed Abu Ayyan

Theses

This study aims to analyze the cooling performance of phase change materials (PCMs) integrated into metallic heat sinks (HSs) both experimentally and numerically. For the experimental part of the study, a test setup has been constructed to test PCM integrated heat sinks. The heat sinks are prepared as metallic containments having fins with fixed inter-fin spacing. The volume between the heat sink fins is filled with PCM namely: a paraffin wax, salt hydrate-calcium chloride and milk-fat, then the whole system is sealed for testing under various heat loads at 4W, 6W, 8W and 10W. Four modes of operation are experimentally …


Effect Of Endplate On The Blast Wave Profile In A Compressed Gas Shock Tube, Sudeepto Kahali Aug 2015

Effect Of Endplate On The Blast Wave Profile In A Compressed Gas Shock Tube, Sudeepto Kahali

Theses

Blast related brain injuries are commonly encountered in the recent wars of Iraq and Afghanistan increased use of improvised explosive devices (IEDs). An estimated 20% of veterans returning from these operations have suffered traumatic brain injuries (TBI). The mechanisms and long-term effects of the injury are not fully understood, and extensive research effort is being focused toward identifying the mechanisms of primary blast injury. When a pure shock-blast wave encounters a subject, in the absence of shrapnel, casing or gaseous products, the loading is termed as primary blast loading, and its effects can be studied using shock tubes.

The wave …


Hand Operated Tabletop Letterpress Assembly Instructions 1.0, George Chiu, Brendan Domos, Spencer Herzog, Nathan Sandidge, Kevin Weinstein Jun 2015

Hand Operated Tabletop Letterpress Assembly Instructions 1.0, George Chiu, Brendan Domos, Spencer Herzog, Nathan Sandidge, Kevin Weinstein

Theses

A group of RIT Mechanical Engineering students spent the 2014-2015 academic year in their senior design class collaborating with the RIT Cary Graphic Arts Collection to design and fabricate a 21st century hand-operated platen press.

The press that was designed during this engineering exercise met several requirements:

  • be under 30 lbs
  • fit in a 24 inch square table top space
  • be manufactured with a majority of components which could be purchased from a standard parts supplier
  • be able to print with commonly manufactured ink rollers, ink, letterpress chases, spacing and furniture
  • the platen and packing had to be adjustable to …


Experimental Evaluate Gas Separation Using Ranuehilsch Vortex Tube, Ali Salah Omar Owiemer Omar Owiemer Jun 2015

Experimental Evaluate Gas Separation Using Ranuehilsch Vortex Tube, Ali Salah Omar Owiemer Omar Owiemer

Theses

Through experimental investigation, this study is offering a closer look into the performance of the vortex tube energy separation and a better understanding of the effect of the vortex tube length, diameter and internal tapering angle on the energy separation. Also the study addresses the effect of inlet pressure on the performance of the vortex tube and the effect of different working fluids (Air, H2 and O2). The vortex tube is a thermal static tube that was discovered by the French scientist George Ranque in 1933 and it is used to separate compressed gas flow into two different streams: one …


Development Of A Finite Element Method For Light Activated Polymers, Craig Hamel May 2015

Development Of A Finite Element Method For Light Activated Polymers, Craig Hamel

Theses

Traditional Shape Memory Polymers (SMPs) belong to a class of smart materials which have shown promise for a wide range of applications. They are characterized by their ability to maintain a temporary deformed shape and return to an original parent permanent shape. The first SMPs developed responded to changes in temperature by exploiting the difference in modulus and chain mobility through the glass transition temperature. However, in recent years, new SMPs have been developed that respond to other stimuli besides temperature; these can include electricity, magnetism, changes in chemical concentration, and even light.

In this thesis, we consider the photo-mechanical …


Preparation And Characterization Of Copper-Doped And Silver-Doped Titanium Dioxide Nano-Catalysts For Photo Catalytic Applications, Haya Abdel Ra’Ouf Ahmed Ra’Ouf Ahmed May 2015

Preparation And Characterization Of Copper-Doped And Silver-Doped Titanium Dioxide Nano-Catalysts For Photo Catalytic Applications, Haya Abdel Ra’Ouf Ahmed Ra’Ouf Ahmed

Theses

The goal of this work was to improve the performance of TiO2 nanomaterials by increasing their optical activities by shifting the onset of the response from the UV to the visible-light region. Among the several ways to achieve this goal, doping TiO2 nanomaterials with other elements (e.g. metals) was selected to narrow the band gap and enhance the optical properties of TiO2 nanomaterials. In this work, we have prepared Cu-doped TiO2 and Ag-doped TiO2 nano-catalysts, characterized them and studied their properties, and the optical ones in particular. The Ag-doped TiO2 catalyst was prepared by the sol-gel method while the Cu-doped …


Carbon Black Mediated Conductive Polymer Composite, Mohamed Hussein Faris Ali Dec 2014

Carbon Black Mediated Conductive Polymer Composite, Mohamed Hussein Faris Ali

Theses

The central goal of this thesis is to produce electrically conductive nanocomposites made out of carbon black obtained from waste tires as filler into a polymeric matrix. Waste tires are discarded in substantial numbers on a daily basis, posing a significant environmental concern. By weight, about 25-35% of a tire is carbon black. Pyrolysis is a convenient and environmental friendly process to produce carbon black from tires. Due to carbon black’s low density, high electrical conductivity and economic feasibility, this thesis investigates the electrical conductivity of nanocomposites that utilizes carbon black particles as fillers. As a result of its modified …


Influence Of Lateral Boundaries In Tapped Densification Of Granular Materials, Nathaniel Ching Jan 2014

Influence Of Lateral Boundaries In Tapped Densification Of Granular Materials, Nathaniel Ching

Theses

Granular systems are widely present in the world. Soil, pharmaceutical pills, and silos filled with grain all are examples of granular systems. Experiments have long established an empirical understanding of granular systems, but an analytical understanding has been much more difficult to establish. One of the behaviors of a granular system that is well documented but poorly understood is the change in density the system undergoes when excited, also known as the densification process.

This thesis investigates the densification process of a tapped granular system using Discrete Element Model (DEM) simulations. Contact interactions in the simulations obey a well-established inelastic …


Magnetic Nanoparticles For Thermally Anoparticles Enhanced Heavy Oil Recovery, Hazem Elshorbagy Elshorbagy Jan 2014

Magnetic Nanoparticles For Thermally Anoparticles Enhanced Heavy Oil Recovery, Hazem Elshorbagy Elshorbagy

Theses

A novel method of delivering thermal energy efficiently to reservoirs for heavy oil production is described in this study. The method uses magnetic nanoparticles that generate heat locally when exposed to a high frequency magnetic field oscillation via hysteresis losses. This concept is currently used in medical research to thermally kill cancerous cells. Electromagnetic heating is a n alternative method to heat heavy oil reservoirs without using water or steam. Using magnetic nanoparticles with electromagnetic heating would greatly reduce the energy requirement and would allow efficient propagation of heat into deeper regions beyond wellbore locality that are otherwise difficult to …


Analysis Of Connecting Rod Bearing Design Trends Using A Mode-Based Elastohydrodynamic Lubrication Model, Travis M. Blais Aug 2013

Analysis Of Connecting Rod Bearing Design Trends Using A Mode-Based Elastohydrodynamic Lubrication Model, Travis M. Blais

Theses

Available design trends for big end connecting rod bearings utilize widely adopted rapid methods for prediction of minimum film thickness due to their superior speed and ease of use. However, they impose unrealistic assumptions such as surface rigidity, which could compromise the accuracy of results. The significance of structural elasticity and updated models was investigated using a mode based elastohydrodynamic lubrication model which includes body forces, mass conserving cavitation, and surface roughness. Eight physical connecting rods were modeled using finite element methods and simulated over a variety of conditions, varying engine speed, bearing clearance, and oil viscosity. The results show …


Conductive Polymer Blends And Their Use In Memory Devices, Mohammad Yousef Al-Haik Jun 2013

Conductive Polymer Blends And Their Use In Memory Devices, Mohammad Yousef Al-Haik

Theses

The aim of this project is to synthesize and characterize conductive polymers made out of blending nonconductive polymers with ionic liquids. An application to demonstrate the use of these novel conductive polymers is to create an organic memory device.

Attempts to synthesize conductive polymers have been reported in the literature; several of these approaches include doping a polymer with arsenic or iodine based dopant. In this work, ionic liquids, known as plasticizer, are sued as the dopant for non-conductive polymers. There are several advantages of employing the ionic liquids over other dopants, including the maintenance of organic based blends (both …


Carbon Dioxide Absorption And Channelling In Closed Circuit Rebreather Scrubbers, Shona Cunningham Jan 2013

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 …


Thermal Characterization Of As4/3501-6 Carbon-Epoxy Composite, Bradley R. Doleman Jan 2013

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 …


Examination Of Thermal Properties Of Carbon-Carbon And Graphitized Carbon-Carbon Composites, Melanie Jene' Patrick Jan 2013

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 …


Study On Fracture Behavior Of Aa5083–H111 Friction Stir Welded Join, Mohammed El Sayed Allam Mar 2012

Study On Fracture Behavior Of Aa5083–H111 Friction Stir Welded Join, Mohammed El Sayed Allam

Theses

The fracture behavior of friction stir welded joints of aluminum alloy 5083-H111 was studied in this investigation. Different samples of stir welded joints at variable tool rotational speeds (1660 rpm, 850 rpm, and 675 rpm), different traveling speeds (24, 42, 55, 74, and 98 mm/min), and different tool pin shapes (cylindrical, tapered and threaded) were studied to investigate the effect of process parameters on the joint strength/load-bearing capacity. A series of tensile tests using an MTS machine, scanning electron microscope (SEM) analysis, and optical microscope analysis was conducted to study the effect of varying the rotational speed, traveling speed, and …


The Mechanical Testing Of Single Nanofiber, Pratik Manohar Dahule Jan 2012

The Mechanical Testing Of Single Nanofiber, Pratik Manohar Dahule

Theses

Polymer nanofibers exhibit properties that make them a favorable material for the development of tissue engineering scaffolds, filtration devices, sensors, and high strength lightweight materials. Perfectly aligned PLLA Nanofibers were fabricated by an electrospinning technique under optimum conditions and the diameter of the electrospun fibers can easily be tailored by adjusting the concentration of the polymer solution. To align the nanofibers, special arrangement was made in terms of two aluminum plates. Good alignment of polymer nanofibers on specimen was confirmed by SEM observation. The effect of different electro-spinning parameters on maximum fiber length, average fiber diameter, diameter uniformity, and fiber …


The Design And Development Of A Substitution Device For The Visually Impaired., Kieran John O'Callaghan Jan 2012

The Design And Development Of A Substitution Device For The Visually Impaired., Kieran John O'Callaghan

Theses

Current sensory substitution systems for the visually impaired are limited in terms of their spatial and depth resolution capabilities. They are unable to relay real-time 3D spatial information regarding objects in the direct path of the user. Recent advances in 3D imaging technology have presented new opportunities to develop improved sensory substitution systems to compensate for visual sensory loss. The present study established the design criteria, designed, manufactured and evaluated the performance of a real-time vision substitution device called VisionRE.

Knowledge obtained from a literature review of Human Machine Interfaces (HMIs), feedback from visually impaired focus groups and 3D electrode …


Design And Fabrication Of A Tapped Densification Apparatus For Bulk Solids, Joshua H. De Jong Jan 2011

Design And Fabrication Of A Tapped Densification Apparatus For Bulk Solids, Joshua H. De Jong

Theses

Experiments are commonly used to ascertain the flow properties of bulk solids. One such property is a measurement quantity known as the tapped density. Here, a container of granular material is subjected to a long sequence of discrete taps, after which the bulk density - the total mass divided by the volume occupied –- is determined. Current technology exists to achieve the maximum tap density by subjecting a container to a user defined number of taps at a specific, predetermined amplitude and frequency. However, the final bulk density is known to be dependent on the tap parameters. It can therefore …


Creep Behaviour Of Hand Laminated Glass Reinforced Polymer Composites., Brain Quinn Jan 2011

Creep Behaviour Of Hand Laminated Glass Reinforced Polymer Composites., Brain Quinn

Theses

The creep behaviour of hand laminated, glass fiber reinforced polyester composites were studied at coupon level, due to the use of similar materials in long term load bearing civil and structural engineering applications. Creep predictions were made by fitting the parameters of several viscoelastic models to experimental creep data as well as two accelerated test methods, time temperature superposition (TTS) and frequency time transformations (FTT). TTS experiments were carried out in a dynamic mechanical analyzer (DMA) in three point bending mode for three types of material systems. Creep compliance master curves representing the linear viscoelastic creep response at reference temperatures …


Design Of A Smart System For Monitoring Concrete Curing And Structural Health, William Quinn Jan 2011

Design Of A Smart System For Monitoring Concrete Curing And Structural Health, William Quinn

Theses

Structural Health Monitoring (SHM) is a rapidly growing sector of the construction industry. Automated monitoring methods arc mainly limited to global monitoring and the application of local monitoring methods has not gained widespread application due to the fact that currently technology requires that the systems are wired to data acquisition devices. This thesis presents a fully embeddable wireless sensor node for the local monitoring of structural concrete. It presents the first reported wireless embedded system implementation of the electromechanical impedance method using both resonant and antiresonant sensors for this purpose.

The first section of this thesis examines the feasibility of …


Fracture Behavior Of Cracked Full Scale Steel Pipes Used For Gas And Petroleum Industries, Jaafer Altarawneh Nov 2010

Fracture Behavior Of Cracked Full Scale Steel Pipes Used For Gas And Petroleum Industries, Jaafer Altarawneh

Theses

The fracture toughness of pipeline steel grade X65 was investigated utilizing linear elastic fracture mechanics analysis, KIC testing according to non-standards techniques, as well as the elastic-plastic fracture mechanics analysis (J-Integral and crack opening displacement COD methods). The fracture toughness tests were conducted at full scale pipe used for gas and oil industry, circumferential surface crack were introduced to nine pipe specimens with different depths, crack/notch depths were selected to cover wide range of remaining material of the original pipe thickness, the original pipe thickness remain unchanged, a special fixture was manufactured to perform the experimental works, plane strain …


Impact Characteristics Of Nano Composites, Ammar Mohamed Al Omari Jun 2010

Impact Characteristics Of Nano Composites, Ammar Mohamed Al Omari

Theses

Nanocomposite materials have seen a significant increase in use and have created a revolution in high-performance structures. They exploit the properties of different materials which create structures that are stronger, stiffer, impact resistant and more durable against environmental factors. They can be tailored to have better electric, magnetic, optical properties, and be chemically, thermally and explosion resistant depending on the application. The current research study investigates the impact characteristics of polymeric based nanaocomposites strengthened with various types of nano and micro filler. An in-house designed impact testing machine was utilized to typify the impact characteristics of different nanocomposite materials through …


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 …


The Future Of The Irish Manufacturing Industry In Relation To Global Competitiveness, Joceley Martins Wilson Jan 2009

The Future Of The Irish Manufacturing Industry In Relation To Global Competitiveness, Joceley Martins Wilson

Theses

This study is an examination of the challenges faced by the manufacturing sector in Ireland. As the speed of globalization intensifies, new demands are constantly being levied on the manufacturing sector. In order to maintain this very important sector in Ireland, the manufacturing industry must promote constant innovation, automation and specialization, specifically in niche areas where there is a requirement for specific specialized skills, and where the labor cost is not a prohibitive or fundamental issue.

Innovation has been a key success factor for the manufactures to date, and will continue to be an ai'ea of focus as competitive forces …


Automated Network Planning For Industrial Ethernet Networks, Holger Machens Jan 2009

Automated Network Planning For Industrial Ethernet Networks, Holger Machens

Theses

Engineers usually use computer aided methods to ease the increasingly complex planning task of automation plants. One such computer aided method for automated planning of Industrial Ethernet networks under given network QoS requirements is presented in this thesis. The method is based on partitioning the given set of network nodes according to specified communication relationships between the nodes, thereby creating subsets of nodes which are joined using given networking algorithms. Several networking algorithms may be applicable for each subset of nodes and any complete solution is a combination of several partial solutions, one for each subset of nodes. Enumeration through …