Improvements on a Battery-Powered Alarm Clock
Ericka
Pruitt, John Horton, Sunish ThomasMathew, and Dustin Burnett
Extended Abstract
Purpose
This project addresses the problem of a battery-powered alarm clock which is convenient for travel, but does not wake the sound sleeper. The primary purpose of this project is to formulate a possible improvement solution. The secondary purpose is to provide an exercise in design formulation.
Methodology
Multiple solutions were proposed during a brainstorming session and then narrowed to a single solution. The selection process included the use of Morphological Charts, Objectives Comparison, Pair-wise Comparison, and Comparative Evaluation. Testing methods were developed to analyze the success of the final design solution.
The improvements decided upon were the addition of a flashing light and a random sound generator. The flashing light was chosen because sleepers are disturbed by the presence of light. The random sound generator was chosen to prevent users from getting used to the alarm sound and ignoring it.
A prototype was then developed to simulate the proposed design changes. After fabrication, the prototype was tested, evaluated, and conclusions were drawn based on test results and designing constraints.
Conclusions
The improved battery-powered alarm clock works very well in concept and practice. The addition of a flashing light was noticeably successful. Time and technical constraints limited the ability to prototype the sound generator. In either case the design objectives were met and the alarm clock retained its compact shape, size and weight.
Recommendations
The addition of a flashing light was successful. There is, however, room for improvement. Other changes or enhancements could be explored in follow on work.
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AFM
ANALYSIS OF FUNCTIONLALLY GRADED ALUMINUM MATRIX COMPOSITES FOR HIGH WEAR
AEROSPACE APPLICATIONS
R.
G. Hidalgo/ Z. H. Melgarejo/ O. M. Suárez
Department
of Mechanical Engineering, University of Puerto Rico- Mayagüez / Department of Mechanical Engineering, University
of Puerto Rico- Mayagüez / Department of General
Engineering, University of Puerto Rico- Mayagüez
Extended Abstract
Functionally-graded materials (FGM) are useful
in applications where high wear resistance and appropriate bulk toughness
are a necessity. The objective
of the present work was to analyze and characterize a novel FGM, which has
been proposed as alternative material for aerospace applications. This FGM
consisted of an Al-B composite prepared by investment casting of Al 5% B alloys.
Upon solidification the material was centrifugally cast using two different
rotation velocities. Therefore,
the main purpose was to characterize the distribution of the AlB2
reinforcing particles embedded in the aluminum matrix, at the micro- and nanoscale. The techniques used were atomic force microscopy
(AFM), and optical microscopy. For
the present project, the AFM, which consisted of a tip on a cantilever that
explores and tracks superficial details in contact with the surface, helped
analyze the topography of the sample. To enhance the topography for the AFM
imaging, the studied samples were slightly etched with 0.5 % HF solution.
The 3-D images allowed identifying AlB2 particles and grain boundaries.
In effect, the location of the matrix grain boundaries with respect to the
diboride location could be observed. This helped characterized surface roughness,
observed surface defects, and determined the size and shape of clusters and
aggregates on the surface. On
the other hand, in the samples analyzed in the AFM that were not etched it
was not possible to identify the diborides.
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Noise Reduction from Use of Fuel Cell Auxiliary Power Units in Lieu
of Truck Engine Idling
Joshua
S. Krause and Christopher Jones
Seniors, College of Integrated Science and
Technology,
Extended
Abstract
The threshold of noise an average human finds annoying or unpleasant is generally 80 dB(A). Most large trucks and buses, which are powered by diesel engines, produce noise of approximately 70 dB(A) during idling. Trucks and buses primarily idle to power heating and cooling. Long-haul trucks, commonly referred to as big rigs, often idle 6-8 hours per day while the drivers rest in the bunk as mandated by law. When a number of these trucks congregate, for example at a truck stop, there is a risk of impaired hearing for drivers and others in the immediate vicinity. At the least, truck idling noise can interfere with driver rest and thus becomes a safety issue. In the last five years, researchers have been examining alternatives to diesel engine idling. The interest in alternatives is primarily due to the desire to decrease air pollutant emissions; however, the additional advantage of reduced noise is often cited. There is no published quantitative data on the noise reduction benefits offered.
We studied the noise reduction potential of one promising alternative, fuel cell power units (APUs). It is well documented that fuel cells themselves produce less noise than diesel engines. Fuel cells are electro-chemical devices similar to batteries, and there is no combustion process and few mechanical parts. However, the actual power devices are not the only sources of noise. Both fuel cell APUs and the main engine provide power for the truck’s main HVAC (heating, ventilation and air-conditioning) system. We hypothesized that the noise from the HVAC system is substantial and that the overall noise from trucks does not significantly differ between the main engine and the fuel cell power source.
Previous studies have shown that the noise emitted by an individual vehicle is a function of many different variables such as the model and year and the physical location of measurement (i.e., inside the truck cab, under the truck, adjacent to the exterior of the truck). Accordingly, this study collected empirical data for a single truck, at various locations inside and outside of the cab, as well as, under various accessory load conditions. The load conditions were added because they would affect the noise level from the HVAC systems. The measurements for the diesel engine under high loads were an average of 63.0, 63.5, 65.7 and 79.0 dB(A) for the driver’s ear, passenger’s ear, bunk and exterior of the truck respectively. The measurements for the fuel cell APU under similar conditions were 39.2, 38.6, 38.5, and 53.5 dB(A) for each noise location respectively. The results indicate that the fuel cell results in a significant dB(A) decrease compared to the diesel APU.
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Caylyne
Shelton, Adrian Drummond and Brandon Edmonds
Embry-Riddle
Aeronautical University
Extended
Abstract
The Eagle Ground Control
System (Eagle) represents the melding of two worlds. Eagle allows real vehicles, navigating
in our world, to interact with virtual obstacles and vehicles in a simulated
airport. Eagle is made up of two major components, a robot known as G-Unit, and
a system called the Ground Control Simulation (GCS). G-Unit can be controlled
via a remote control or by the GCS. G-Unit is expected to follow movement
commands, and make reports to the GCS that include its current location and any
obstacles it has encountered. The GCS will ensure that all movement on the
airport surface conforms to standards as defined by the Federal Aviation
Administration (FAA). Should a vehicle (simulated or G-Unit) under manual
control threaten to break FAA separation rules, the GCS will reroute the
necessary vehicle(s) to maintain separation integrity. Eagle allows us to create strategies for
routing and communication that may one day allow for the automation of airport
ground traffic.
The creation of Eagle
required a multidisciplinary team that joined the skills of hardware design with
those of software creation. The project consists of 15 engineers assembled into
three teams: one team of four computer engineers (mainly responsible for
hardware design and implementation), and two teams of software engineers (one
mainly responsible for the design and implementation of the GCS, and the other
responsible for the firmware that resides on G-Unit for its control, and
communication between G-Unit and GCS).
Within each team, roles are assigned based on individual knowledge,
academic performance, and experience.
The team member roles are: Team Leader, responsible for overseeing all
team activities; Development Manager, responsible for tasks from design through
implementation and maintenance; Planning Manager, in charge of establishing
schedules and maintaining metrics for all phases of the engineering process;
Quality Manager, who documents defect information and ensures the integrity of
all products produced by their team.
As
part of our design process, we had to make sure our project was within the
allocated cost, power, performance, and time constraints. Using the Parallax Javelin Stamp as the
brain of the G-Unit allowed us to best balance all of these factors. The cost,
ease of use, and power of the stamp made it the clear choice for our project.
However, the stamp introduced another level of complexity, its memory
limitation. As a result we were
forced to redesign our firmware in order to meet our memory limitations and
implement part of the G-unit control within the overall GCS functionality. This
was easily accomplished since the GCS treats physical vehicles the same as
virtual ones. A small interface layer let’s each vehicle implement each command
differently. In addition to resolving our memory constraints, this approach
allows for flexibility and leaves room for additional vehicles and vehicle types
to be added to the system.
Our
initial results from unit, integration and system testing confirm that the
system under design meets all the stated requirements of the system.
Nafion-BIMEVOX
Composite Membrane for Fuel Cell Applications
Richard
A. Lawson
Proton exchange membrane (PEM) fuel cells using Nafion (®DuPont) as an electrolyte are among the most promising low temperature fuel cells currently in development, but they suffer from carbon monoxide catalyst poisoning at levels as low as 10 ppm. Insertion of ceramic oxygen ion conductors into the Nafion membrane should allow higher levels of carbon monoxide tolerance due to oxygen ion transport from cathode to anode through the ceramic, which will remove carbon monoxide from catalysts. Composite polymer-ceramic membranes made using the BIMEVOX family of ceramic oxygen ion conductors and Nafion were synthesized and characterized. The BIMEVOX ceramics were made from the corresponding metal oxides and synthesized using standard solid-state reaction. Different compositions of BIMEVOX ceramics were tested using ac impedance spectroscopy at different temperatures to measure the amount of ionic and electronic conductivity and determine the composition with the highest low temperature ionic conductivity. Cyclic voltammetry was performed on ceramic samples in trifluromethyl-sulfonic acid to test its electrochemical stability in Nafion and a fuel cell environment. Composite membranes of various amounts of ceramic were made, and membrane conductivities were determined in air and water. The composite membranes were put into fuel cells and tested under a variety of conditions and CO levels to determine the effect of the ceramic on the performance of the fuel cell. Bi2V0.75Sb0.25O5.5 was determined to have the highest ionic conductivity at low temperatures. The cyclic voltammetry showed that the ceramic was stable in fuel cell conditions over the range of operating voltages.
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ANSYS Analysis of the Mini Baja Frame
Brad Smith, John Parker, Colby
Todd, and Matt Franks
Extended
Abstract
Introduction
Eagle Motor Sports at Georgia Southern University takes part in the Mini Baja East competition on an annual basis. The 2004 frame was designed by the SAE rules and minimum regulations and not by researching and analyzing the best possible frame components. In order to improve the design of the frame, Finite Element Analysis was introduced. ANSYS university intermediate version was used for this purpose.
Modeling and
Analysis
Two frames were analyzed for steady loads using frame weight, engine weight, and driver weight. The first frame analyzed was that of a 1.00 inch OD with wall thickness of 0.083 inches, and the second frame analyzed was that of 1.25 inch OD with wall thickness of 0.049 inch. Also, the impact load was estimated for a frontal collision at a speed of 10 mph and subsequently a new tube size was recommended. In these analyses pipe elements were used for modeling in ANSYS.
Results
The weight of both frames from the static loading were calculated and compared to one another. It was concluded that the 1.25 inch OD to be 29.3 percent lighter than the 1.00 inch OD frame because of the decrease in wall thickness. It was found that steel tubing of 1.25 inch OD with wall thickness of 0.049 inch was sufficient for the frame itself. The analysis of the 1.00 inch OD frame with static loads produced a maximum von-Mises stress of 6124psi while the 1.25 inch OD yielded only 5687psi. The maximum vertical deflection with the later case was 0.0509 inches. In order to make the vehicle safe for the impact loading, a frame of 1.688 inch OD with wall thickness of 0.065 inch was found suitable. Only the front member had to be much larger in size (3.5 inch OD with a wall thickness of 0.172 inch) in order to withstand the impact. With that design the maximum von-Mises stress, in case of a point impact load at the center of the front member, was found to be 50ksi.
Discussion
and Conclusion
The results for Static loading were reasonable. The impact loading simulation needs further investigation. The software capabilities of ANSYS university intermediate version 8.1 was limited and did not include the impact loading feature needed to perform proper analysis of an impact load. Also, the strengthening effect of the front panel was ignored in the analysis. Overall the analysis was an extremely helpful exercise that gave a better understanding of the effects of various loads on the frame.
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Rapid-Prototyping
Assisted Product Design
Tony
Majka
Senior
Mechanical Engineering Student – The
Extended Abstract
The design process extends far beyond the realm of concepts. The objective this project is to realize the concepts, using rapid prototyping, in a reasonably short time.
Rapid-prototyping employs modern technology to diminish lead time and design cost. By applying rapid-prototyping technologies in the product development phase, designers have a vast array of possibilities. Engineers are able to quickly and economically identify and improve design flaws. Rapid-prototyping presents designers with the opportunity to quickly have an inexpensive working model of their design to identify potential design shortcomings such as; assembly issues, human factor, and manufacturability. Rapid-prototyping also offers designers a more effective, “hands-on” way of communicating their design concept to other departments (i.e. marketing).
The design of a cup and lid set to meet a short list of constraints was used to demonstrate the process of product design through rapid-prototyping. The design objectives were to create a functional, aesthetically pleasing cup that will fit into a 3” x 3” x 5” box. The cup must have a threaded lid, and be held comfortably by an average hand. The design must consider assembly, manufacturability, and human factors.
The project involved using 3D CAD software to design the part which met the given set of criteria. The CAD model was used for rapid prototyping through the process of Fused Deposition Modeling to create a working physical model. The model was used to identify design flaws. The model was then measured for dimensional and form accuracy using a coordinate measuring machine (CMM).
The outcome of the project is a solid prototype which, after a few revisions, meets the criteria set; and an understanding of rapid prototyping process capabilities and limitations.
Team Members:
Yizhuo Zhang – Graduate Student
– The
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Design
Considerations for Small-Scale Hydrogen Fueling Stations
Matthew
B. Unger and Patrick J. Commerce
Undergraduate Research Assistants of the College
of Integrated Science and Technology,
Extended Abstract
Hydrogen is an attractive alternative fuel because it
has the potential to reduce foreign oil dependency, as well as air pollutant
emissions. The
The hydrogen fueling station was designed to provide hydrogen
to a 5 kW proton exchange membrane (PEM) fuel cell that will operate for 10-12,
24 hour periods annually. The
fuel cells will provide back-up power for critical air quality analyzers during
frequent power outages at
We concluded that a particular unipolar alkaline-based system would be selected based on its superior pressure capabilities (7000 psi) and the manufacturer’s willingness to share confidential design information. Disadvantages of the electrolyzer include less production (scf/hr) capabilities, few previous in-use application, and higher maintenance. Due to the modest budget, only hydrogen fueling at moderate pressure of 2500 psi was possible because funds were not available for the balance of plant systems needed to fuel at the electrolyzer’s high pressures. However, the system was designed to be easily scaled up in the future for fueling of vehicles at 5000 psi. This paper discusses in detail the design comparison for both the initial and scaled-up systems, and we present our final design complete with a list of cost, part numbers and suppliers for each component. The initial system is currently being implemented at JMU.
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Design and Testing of a Combustion Air Flow Measurement
System for Small
Internal Combustion Engines
Christopher
T. Avans, Joshua L. Kirkpatrick,
Joseph E. Meadows, Derek P.
Morin
Extended Abstract
During the fall 2004 semester, the Senior Mechanical
Engineering Experimentation Laboratory class at
Based on the outcomes of the previous experiments, the need for more precise experiment instrumentation became apparent. To achieve this, we will design a new measurement system, fabricate the new equipment, and test the various devices to measure low air flow rates compatible with small internal combustion engines. The concept design for this measurement system, as well as the outcomes of this design process, will be presented at the 2005 ASEE Southeastern Section Annual Meeting.
To obtain accurate data from the new experimental apparatus, a LabVIEW application software package will be developed and used during this design process. The developed system will demonstrate that it does not alter the normal operation of, or the exhaust emissions produced by, the device. Air flow rates being determined experimentally will be compared with data provided by manufacturers when applicable.
The design group consists of four students with two faculty advisors. Christopher Avans will serve as the team leader, while Joshua Kirkpatrick will program the LabVIEW interface. Derek Morin, who has prior experience working with IC engines, will be the instrumentation specialist. Joe Meadows will serve as the chief fabricator for the new apparatus parts. All members will be involved in conceptual design, construction, apparatus testing, analysis of results, and poster presentation.
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Comparative Emissions Testing of Old and New
Technology
Chainsaws
Jonathan J. Chandler, Mark S. Gilbert,
Jason R. Foley, Noah J. Holcomb
EXTENDED ABSTRACT
During fall 2004 semester the Senior Mechanical Engineering
Experimentation Laboratory class at
The spring 2005 student group will design a test plan, fabricate a measurement system, and complete testing of the new catalytic chainsaw and a very old model (1970 Homelite). The results of this emissions testing coupled with that completed in 2004 will provide comparative emissions and emission factors that show how over the past thirty five years the chainsaw industry has made progressive emissions improvements that contribute to improved air quality. A LabVIEW application software package will be developed and used during the design process. The developed experimental system will demonstrate that it does not alter the normal operation or exhaust emissions produced by the device. The California Air Resources Board and EPA emissions factors for chainsaws will be used for comparative analysis.
The design group will be lead by a student project manager with individual tasks being performed by designated students. The poster presentation will be developed and presented by the student group.
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Computational Fluid Particle Dynamics Modeling and Simulation in
Human Lung Airways
Christopher
A. Basciano, Adam D. Land, Emil H. Pham, and
Sinjae Hyun,
Ph.D.
Department of Biomedical Engineering,
EXTENDED
ABSTRACT
Purpose
Fine (1-10 micron) particles may be the true culprit behind increased respiratory-related illnesses as these particles are inhaled into the respiratory system. Air entering the body travels down the trachea and bifurcates into two bronchi (one for each lung). About ten bifurcations are present between the trachea and alveoli. The 5th through 8th generations were chosen because micron sized particles commonly deposit here. The focus of this research is the flow structure interactions and particle transport throughout the 5th – 8th generations of the lung airways.
Methods
For this study, the 5th-8th generation
bifurcations have been modeled and analyzed using the computational fluid
dynamic modeling program CFX 5.7 (ANSYS Inc). Several flow conditions were used
including two steady-state physiologically significant Reynolds numbers (one for
normal breathing and one for labored breathing) and two different inlet velocity
profiles. The geometry has a total number of 205,456 elements and was created
based on the experimental model from previous research. No-slip conditions were
used for each bronchial wall, and a uniform pressure boundary was prescribed for
the outlets. To simulate the transport of micron sized particles, trajectories
of 200 spherical particles of each diameter listed were computed (i.e. 1, 5, and
10 µm diameters) and tracked from the inlet to the exits or the location of the
particle deposition. The transport of particles and flow of air was modeled
using
Conclusions
A phenomenon known as horseshoe vortical flow was encountered during specific simulations. From the analysis of the data, in order to observe vortical flow conditions, the Reynolds number must be representative of heavy breathing within the lungs and exhibit parabolic velocity profiles. For the study of particle deposition, it was concluded that larger size particles have a higher probability of deposition because of inertial laws. Therefore, the 10 micron particles generally deposited more often then the 1 micron size particle. In other words, 10 micron size particles would usually not reach past the 8th bifurcation, whereas, the 1 micron size particle usually reached the exit of the 8th bifurcation.
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Computational Particle Hemodynamics Simulations in Carotid Artery Bifurcation
Stacie Hamel, Travis Blackburn,
Christal Garner, and Sinjae
Hyun, PhD.
Biomedical Engineering Department,
EXTENDED ABSTRACT
The
main goal of this computational study was to establish flow patterns through a
carotid artery bifurcation to further understand atherosclerosis. This study considers the differences in
particle hemodynamics produced by varying the Reynolds
number in Newtonian and non-Newtonian flow simulations. It also considers the hemodynamics of transient flow as opposed to steady-state
flow. Others have studied flow
through the carotid artery bifurcation; the purpose of this study is to analyze
three-dimensional flow patterns in the carotid sinus.
Continuity, Navier-Stokes, and particle transport equations were solved
using CFX 5.6 (ANSYS Inc.) commercial unstructured finite volume based software,
and velocity, wall shear stress, and monocyte and
platelet transport patterns (including particle deposition) were computed. Transport properties of a physiologically
realistic fluid were created using values for whole blood as well as blood
plasma, and realistic particles were included containing the characteristics of
monocytes and platelets. The ratio of mass flow through the
internal carotid artery (
Results in this study show
velocity within the carotid artery increases with an increase in Reynolds
number. Velocity of fluid flow
through the ECA is greater than velocity through the
Wall shear stress (WSS) was
greatest at the division wall except for a small area of zero wall shear stress
at the stagnation point. Maximum
and area-averaged wall shear stresses in the sinus wall and the division wall
increased as Reynolds number increased, for both the Newtonian and non-Newtonian
simulations. For instance area-averaged
WSS at the sinus wall for the Newtonian simulation was 0.228 Pa for a Reynolds
number of 250, 0.370 Pa for Re = 450, and 0.537 Pa for Re = 1200.
When considering Newtonian flow with Reynolds number = 1200, the area-averaged
WSS values at the sinus wall and the division wall were 0.537 Pa and 0.851
Pa, respectively. Non-Newtonian flow exhibited area-averaged
WSS values at the sinus and division wall of 0.819 Pa and 1.082 Pa, respectively.
Non-Newtonian flow displayed higher maximum and area-averaged WSS than
Newtonian flow, but in all cases the WSS was less than the maximum acceptable
WSS of 40 Pa. This trend was observed in the Reynolds
number = 250 and 450 cases as well.
A larger area of low WSS was seen in the sinus in the non-Newtonian
simulations than in the Newtonian simulations for each Reynolds number. Particle deposition at the sinus wall
and the division wall, for both monocytes and platelets,
was greater with a greater Reynolds number. Therefore a higher WSS correlates with
a greater particle deposition.
Impact of Atherosclerotic
Occlusion Position on Hemodynamic Parameters in the Coronary Artery
Kala K. Cartwright,
Stephanie R. Jackson, and Sinjae Hyun, Ph.D.
EXTENDED ABSTRACT
The coronary arteries are the most prominent site in the circulation for deposition of atherosclerotic plaques. The accumulation of atherosclerotic plaques leads to coronary artery disease and can result in myocardial infarction. Atherosclerosis has been linked to several factors, including anatomical geometry, wall shear stress, and local non-uniform hemodynamics.
Flow through a curved tube model of the left circumflex artery (LCA) was investigated computationally to examine local non-uniform hemodynamics parameters using CFX 5.7. These parameters include changes in wall shear stress (WSS), velocity (V), and pressure (P) due to the position of an atherosclerotic occlusion within the artery. Steady flow simulations (Re = 233) were performed with parabolic inlet velocity for four occluded models and the non-occluded case. An occlusion of 50 area reduction was positioned either in the inner, outer, front, or symmetric (inner and outer) walls of the geometric center of the LCA.
The occluded artery experienced higher maximum and average velocities than the non-occluded artery Vmax, n = 1.41 m/s and Vavg, n = 0.938 m/s, with average increases of 47.7 % and 3.31% (σmax = 5.4, σavg = 1.4), respectively. The maximum velocity was localized in the occluded area and the first part of the exit curvature. All LCA simulations exhibited secondary motion, due to the curvature of the LCA and stenosis. Secondary motion increased in occluded cases relative to non-occluded (inner < outer < symmetric < front). Recirculation was observed immediately following the occluded region in the front occlusion, but was not observed in any other case.
For the non-occluded case, the mean WSS was nearly 3 times greater on the outer wall (τmax, n = 28.2 Pa) than the inner wall. Assuming low WSS increases plaque deposition, this observation is consistent with the theory that the inner wall experiences higher plaque deposition. Each occluded case showed an increase in maximum WSS. The symmetric case showed the largest increase (22.1% > τmax, n), followed by inner (16.5%), outer (4.7%), and front (1.0%) occlusions.
For the non-occluded case, pressure decreased steadily from inlet to exit. Pressure analysis revealed negative pressure in the center of each occlusion and in the LCA exit. A slight pressure increase was observed after the occlusion, but the location of the occlusion does not appear to affect the location of the increase in pressure.
These results demonstrate that occlusion position can be related to both increased velocity and wall shear stress. The recirculation zone produced in the front occlusion model could indicate increased disease severity for occlusions in that position.
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I-QSAR
Studies Using Signature on COX-II Inhibitors
Extended Abstract
Quantitative structure-activity relationships (QSARs) provide a description of the correlation between the structure of a molecule and a specific molecular property of interest, namely the biological activity with respect to a particular substrate. By using a database of molecular structures and corresponding properties, a QSAR model can be developed. The inverse-QSAR (I-QSAR) problem seeks to discover a new database of molecules using the QSAR model in reverse. In other words, the model is used to predict structures for a given activity value using the relationship. While there are many descriptors that can potentially be used to solve the I-QSAR problem, the Signature descriptor is the most practical because it possesses the most important criteria for an excellent descriptor in this area: the generation of a good QSAR, low degeneracy of solutions, and an easy path from solutions to new compounds.
In these studies, a set of 600+ Cyclooxygenase-II (COX-II) enzyme inhibitors and their corresponding biological activities were used to derive four types of QSAR models: one model for each type of biological cell tested in the literature (at three different Signature heights) and one comprehensive QSAR model. The three types of biological cells used in the literature include: purified human recombinant, Chinese hamster ovary (CHO) cells, and human whole blood (HWB). Each model was then solved inversely using the Signature technique to generate a completely new set of molecules within a desired biological activity range.
The HWB models
were developed first. There were
10 unique height 0, 52 unique height 1, and 138 unique
height 2 Signature descriptors found for the 35 compounds. The heights 0 and 1 QSAR models were found
to be fifth order polynomials and the height 2 QSAR model was found to be
an eighth order polynomial. There
were twenty Diophantine constraint equations generated to solve the I-QSAR
problem.
The purpose of
this research was to generate a set of molecules (not previously studied)
to recommend for biological COX-II inhibition testing. These promising results indicate COX-II
inhibitors that could potentially replace Celebrex
and Vioxx, which are found to have unwanted cardiovascular
side effects. Although pharmaceutical
companies are not using this technique, previous research in this group has
demonstrated the utility of the Signature descriptor in solving the I-QSAR
problem using ICAM-1 inhibitors. Two
molecules generated from this method were tested and found to be the
most potent ICAM-1 inhibitory peptides discovered to date.
HAA5
and TTHM Concentration Modeling in Drinking Water Distribution Systems: The
Importance of Chlorine Residual
Douglas
W. Kilgour and Dr. Kevin C. Bower
The
Citadel
Extended Abstract
Total trihalomethanes (TTHM) and the five haloacetic acids (HAA5), known collectively as disinfection byproducts (DBPs), are formed when natural organic matter (NOM) in the form of dissolved organic carbon is exposed to chlorine. The United States Environmental Protection Agency (USEPA) will soon require municipalities to reduce TTHM levels to 80 μg/l and HAA5 to 60 μg/l due to their carcinogenic effect. As municipalities attempt to reduce DBPs to these levels, it is important for them to understand the key parameters of water quality to meet the regulations. Montgomery Watson and others have previously developed models to determine DBP concentrations that are based on chlorine dose at the water treatment plant. However, chlorine residual is not included in these models, though the EPA and others have identified it as an important parameter. While dose concentrations at treatment facilities are similar, chlorine residual will vary depending on the nature and amount of TOC and the presence of pipe deposits. This study seeks to identify the significance of the role of chlorine residual on DBP formation in the drinking water distribution system. The process employed to study the effect of chlorine residual on DBP models included: 1) the generation of a model to accurately predict chlorine residual at any location in the drinking water distribution system and 2) the generation of two regression models using several parameters indicated in literature as important to DBP formation. One of these regression models is based on chlorine dosage as a parameter while the other is based on residual. Both models are presented and conclusions based on the importance of chlorine residual for predicting HAA5 and TTHM formation throughout the drinking water distribution system are provided.
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I-QSAR Studies Using Signature on DHFR Inhibitors
Robyn
D. Rawlings and Dr. Donald P. Visco,
Jr.
Extended
Abstract
Toxoplasmosis and Pneumocystis carinii pneumonia (PCP) are responsible for deaths of patients afflicted with compromised immune systems, specifically those who have acquired immunodeficiency syndrome (AIDS). Current research suggests the existence of undiscovered therapeutic agents that might be useful for treatment of toxoplasmosis and PCP by inhibiting P. Carinii dihydrofolate reductase (DHFR) and T. gondii DHFR. DHFR is an enzyme that plays a crucial role in the building of DNA and other cell processes. Experimental data regarding inhibitory effects (IC50 values) that newly synthesized molecules exhibit against pcDHFR and tgDHFR are available. Using a database of these results, a mathematical algorithm using the Signature descriptor can be used to generate a QSAR (quantitative structure-activity relationship) and ultimately to solve the inverse-QSAR for compounds with low IC50 values (strong inhibitors). The goal of this research is to create a focused database of novel molecular scaffolds, specifically those that exhibit high selectivity and low toxicity when targeting pc and tg DHFR, for future testing by pharmaceutical companies conducting drug research.
The methodology used to predict molecules that could be potentially useful in this DHFR study is based on the Signature descriptor. The Signature descriptor is first used to relate a compound’s inhibitory activity and molecular structure. An atomic Signature is found using a variety of heights (user specified) from the root carbon atom. The occurrence of vector solutions (descriptor values) for each atomic height is added together to find the molecular Signature. When compared to other less ideal, but frequently used descriptors, Signature appears to be the superior choice. Signature is an excellent way to obtain a valid QSAR that has a low degeneracy. The descriptor is unique because it provides a clear way to go from the numerical I-QSAR solution to a new molecular structure. Although pharmaceutical companies are not currently using Signature to help create focused molecular databases, Signature has proven useful in past scientific studies. The Signature descriptor was used to help solve the I-QSAR problem in a study of ICAM-1 inhibitory peptides (Journal of Molecular Graphics and Modelling 22 (2004) 263-273). Two of the molecules predicted using Signature proved to be the strongest inhibiting peptides to date after synthesis and testing in-vivo.
There are 385 molecules in the data set considered for the forward-QSAR and I-QSAR problems. The first set used to solve the QSAR problem consisted of 177 T. gondii cells grown in Chinese hamster ovaries. Results of molecular scans at heights 0, 1, 2, 3, 4, and 5 appear promising and the number of unique descriptors found was 14, 92, 379, 922, and 1661, and 2343, respectively.
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Engineering
with a Purpose: Water of Life
Karla
Childress, Kris Hatchell, and Katie McDonald
Extended Abstract
The mission of the engineering programs at
The CEDECO facility had a sporadic spring-fed water supply that was very unreliable. To improve this situation, the team of Lipscomb students designed a system that included a tank in the ground that held water from the spring, a tank on top of a steel water tower, a solar array powering a pump to fill the top tank, and a distribution system to supply adequate water pressure for the facility. The project was broken down into smaller tasks, and the students were divided up into three main technical teams: tower design, pump requirements, and solar pump selection. Additionally, students worked on other tasks such as the fundraising, the materials list, and the work plan.
The design of the water tower and pump system was based on the water
needed for a period of concentrated activity at CEDECO such as a vaccination
campaign. It was determined that
300 gallons of water would be sufficient, and the tower was designed to support
that load, expected wind loads, and allow for a structural safety factor. The height of the tower and the size of
the pipes on the distribution system were interdependent, and tower height
was ultimately chosen based on the longest length of angle iron (20 feet)
that was readily available in
The team
did extensive planning and testing to be sure all materials, equipment and
tools would be taken with them or available in
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Dielectrophoretic Determination of Erythrocyte
Properties for Medical Diagnostic Microfluidics
Kellie M. Smith, Patrick T.
Jouben, Adrienne R. Minerick
Motivation
Donor blood in storage can be
preserved up to 6 weeks under normal conditions. However, some blood samples may not be
viable this entire time, while others may remain viable beyond 6 weeks. The new Medical micro-Device Engineering Research Laboratory (M.D. - ERL) in chemical
engineering is exploring dielectrophoretic microdevices with the goal of creating a device to determine
the viability and blood type of
donor blood in storage from a single drop of the blood.
Background
Dielectrophoresis is the movement of particles in a non-uniform
alternating current (AC) field. Under the influence of a non-uniform AC field,
charged particles become polarized and move due to the dielectrophoretic force. Erythrocytes, more commonly known as red
blood cells (RBC’s), are ideal candidates for dielectrophoretic characterization because they have
negatively charged membranes and highly conductive interiors. Previous work
performed by Adrienne R. Minerick showed that a
resonant frequency at 1 MHz exists for A+ blood. Due to the polarizability of cells, each species is susceptible to
certain AC frequencies that are known as the cell’s resonant frequency. Genetically or geometrically similar
cells have more similar, but still distinct, resonant frequencies. Preliminary
dielectrophoretic screening experiments of human A+
red blood cells were performed and suggested further
work is needed to fully understand the cell's behavior.
Methods
A microdevice made with 100 micron platinum wires sandwiched
between two nonconducting plates is employed to
characterize and determine the dielectrophoretic
response of red blood cells in storage. Whole blood was stored in the
anticoagulant EDTA in a refrigerator at 5oC. Samples were prepared by diluting whole
blood with physiologically balanced 0.143M sodium phosphate buffer. A Zeiss Axiovert 200M inverted light
microscope with a high resolution Axiocam camera
recorded images of the experiment as a video. Each blood type was tested at six
frequencies over the span of six days and at 500 kHz over the span of three
weeks.
Results
The dielectrophoretic response of the red blood cells included
the formation of chains of cells along field lines and movement of the cells
away from a pointed electrode and toward a flat electrode, each of which were
frequency dependent. Dielectrophoretic characteristics
such as RBC chain lengths, number of RBC chains formed, and repulsion from the
high field electrode are quantified for four blood types: A+, O+,
Department of Engineering, Western Kentucky University
Western Kentucky University offers an introductory course in electrical engineering for freshman. This course revolves around an autonomous robot project. The goal of the project is to design and build an autonomous robot capable of completing a predefined course. The course consisted of an elevator and rectangular track. It was vital for the robot to sense its environment while navigating the course. Each team member designed and built the robot’s body and programmed a BASIC stamp microprocessor. The programming of the processor would later act in unison with the sensor design to evoke specific responses from two modified servo-motors.
In building our robot we were introduced to circuitry programming and wiring as well as fabrication tools. The project also allowed for the development of skills required by engineering professionals within a work place. By working in cooperation with a partner we were able to formulate and enact a plan of action while remaining within given time constraints. In doing so we increased our ability to work as a team and troubleshoot specific problems while honing our time management skills.
The track itself consisted of two levels, the lower half with a straight track which led to a lift that carried the robot to a rectangular track above. The rectangular track itself was 9” wide which was considered during the body design process. Also a consideration was the lift that was on a 5 second time delay and required additional programming that would allow the robot to “sleep” until reaching the second level.
The design of the robot was left to the individual teams as well as any available materials needed to construct the body. The given materials including the BASIC stamp microprocessor, two plastic wheels, a rolling caster, a two modified servomotors. Lexan was used to produce a platform that held the two servomotors and the basic stamp as well as a rolling caster affixed to the front of the platform for increased mobility. A modified clothes hanger and bumper sensors were designed to act as “whiskers” for the robot which would cause a programmed response when contact was made with the walls of the course.
A competition was held for all participating teams in which the robot was required to make a successful pass on the track given three opportunities. The robot, as designed, successfully completed each of the three passes in the fastest time. The robot was also voted best design by the other participants in the project.
The autonomous robot project was a valuable hand’s on experience. The project
gave a good introduction to electrical engineering. This project is a good
example of Western’s vision of Project Based Learning.
Azelaic acid is a diacid used in the production of several plastics and lubricants. It is generated via ozonation of oleic acid. An azelaic acid plant with a production rate of 1000 lb/hr (85% purity) was designed as part of the requirements of the Plant Design Course. Process flow diagrams and operating conditions for the design were obtained from expired patents and refereed publications. Bulk prices for reactants and products were provided by an azelaic acid manufacturer. The ChemCAD process simulation software was used to model the reaction, separation, and purification blocks of the design. The reactor block consists of the oleic acid oxidation reactor and an ozone generator. Distillation and crystallization are applied to separate and purify the products.
The oleic acid feed solution rate was 1540 lb/hr and generated 900 lb/hr (94% azelaic acid) and 700 lb/hr (92% pelargonic acid) with the balance consisting of caproic and malonic acids. Pelargonic acid also is a valuable product used industrially as a herbicide to stop the growth of weeds and as a blossom thinner for fruit trees. Capital investment and manufacturing costs were calculated to determine the profitability of the plant. The Capcost software was used to perform cash flow analysis and a Monte Carlo simulation. The discounted net profit after taxes was $49 million, which was determined using a plant life of 20 years and 9.5 years of straight line depreciation. The discounted payback period and the return on investment were 2.4 years and 40%, respectively. The poster will describe the ChemCAD simulations, equipment specifications, and profitability evaluations.