Digital Commons Network^™

A Framework For Improving Software Reusability Within Quality Constraints., Shawkat Guirguis

Mansoura Engineering Journal

In this paper seven of the most important issues in software systems development have been investigated. These issues address two aspects, namely: software development productivity and the final overall quality. For the productivity aspect, an approach has been devised relying on using scripts. Built as a result of an analyst-user collaboration, these scripts, upon interpretation, transform given user requirements into code. This prototyping approach, in addition to being rapid, involves the user in order to ensure his overall satisfaction with the final product. For the quality aspect, a two-layered repository of thoroughly tested and verified reusable software components has been …

The Effect Of Vehicle Suspension System Components On The Ride Comfort Due To Road Roughness., Ashraf Shaaban, Yousef Abo-Mossalam, Kamal Abed, Nihad El-Chazly

Mansoura Engineering Journal

The aim of the present work is to investigate theoretically the vibration characteristics of the driver body components due to road surface irregularities, when changing the characteristics of suspension system components, A mathematical model representing the vehicle and the driver, and contains five degrees of freedom, has been built-up and analyzed. A computer program has been written based on the transfer matrices concept, and used in the frequency range up to 15 Hz, Finally, this work is considered a step towards obtaining useful technical protection data against vibration. The results indicate that the vibration characteristics of the driver body (ride …

Stability Of Frequency Control Of Power Generating Systems Based On The Sliding Mode Technique., F. Areed, Mohamed Salem

Mansoura Engineering Journal

In the present paper, a new algorithm for solving the control problem in electrical power systems, is introduced. This new algorithm is based on the sliding mode property existing in variable structure system (VSS). The resulting control law is discontinuous by its nature. However, it does not require accurate informations about the system parameters or its manner of variation. The only requirements are the maximum and minimum limits of variation for each parameter, An adaptive controller is designed for an electrical power system, on the basis of that new algorithm The main function of the controller is the frequency control …

The Evaluation Of Natural Ventilation Inside Residential Building Spaces In New Assiut City-(At Under Heated Period) - Egypt., Ezzat Morghany, Abdel-Monteleb Aly, Riyad El Shemeiri

Mansoura Engineering Journal

The movement of air has a great effect on architectural formation whether on the building level in terms of the shape of voids and the ventilating elements or on the level of the general planning of the whole area. controlling roads and passageways. directing housing units, and proper distribution of buildings becomes an essential factor lo provide the required natural ventilation for all buildings, Because of the absence of adequate field studies of housing gatherings in desert arias, in the Under Heated Period, the present research focuses on studying natural ventilation of Housing units in the Under Healed Period through …

Study Of Heat Pipe Performance With Water/ Water-Based Nanofluid., Mohamed Saafan, Elsayed Elshafei, Osama Ali Ebraheem

Mansoura Engineering Journal

Thermal performance of a flat heat pipe cooling system is experimentally investigated. Pure water and Al2O3-water based nanofluids are used as working fluids. An experimental setup is designed and constructed to study its performance under different operating conditions. The effect of working fluid, filling ratio, volume fraction of nano-particle in the base fluid, and heat input rate on the average heat transfer coefficient and in turn the average Nusselt number are investigated. Total thermal resistance of the heat pipe for pure water and Al2O3-water based nanofluid are also predicted. Correlation is obtained to predict the influence of Prandtl number, filling …

Augmentation Of Solar Still Performance Using Flash Evaporation., A. El-Zahaby, A. Kabeel, A. Bakry, S. El-Agouz, O. Hawam

Mansoura Engineering Journal

A new design of a stepped solar desalination system with flashing chamber is experimentally investigated. The main objective of the investigation was to study the performance of step—wise water basin coupled with a spray water system by augmenting desalination productivity through using two air heaters. The effect of using the spray system for seawater is investigated experimentally at different velocities of the water sprays holder and Flow rates on the performance of the solar still in a previous article by the authors [ll. in the present article the effect of the inlet raw water temperature (at motor speed of 250 …

Wailing For My Cultura: Disenfranchised Grief Among Mexican Americans Navigating A Bicultural Identity, Sandra Ramirez

Open Access Theses & Dissertations

There is a gap in grief research in the field of Communication that is related to the Mexican American experience. Mexican Americans navigating two often opposing cultures may experience additional complications as they attempt to maneuver the differences in grief rituals that align with either American or Mexican customs. This may result in the bereaved experiencing disenfranchised grief. This study aims to examine the significance of Mexican American bicultural grief rituals as a third option to determine how that relates to disenfranchised grief.

The first part of this study is a textual analysis of media coverage of Mexican American grief …

Computational Study Of Grain Structure Evolution In Cdte/Cds Via Molecular Dynamics, Sharmin Abdullah

Open Access Theses & Dissertations

Grain structure analysis plays an important role in the identification of grain boundary characteristics, which can affect the efficiency of Cadmium Telluride/Cadmium Sulfide (CdTe/CdS) solar cells since they can act as recombination centers for carriers. Computer simulations such as molecular dynamics (MD) can be a very convenient and cost- effective method of investigating the growth evolution and grain structure of materials. The recently reported and experimentally validated MD simulated growth of polycrystalline CdTe/CdS films shows that these materials mostly consist of zinc blende (ZB) and wurtzite (WZ) structures, along with highly disordered atoms. However, little information about the semiconductor compound …

¡Sí Se Puede!: Understanding The Experiences Of Latina Students During Their Doctoral Journey At A Hispanic-Serving Institution, Flor Del Rocio Acevedo

Open Access Theses & Dissertations

The existing body of literature on Latinas has mostly been focused on the undergraduate student experience (Hernandez, 2002; Hurtado et al., 1996; Kena et al., 2016; Tinto & Goodsell, 1994; Torres, 2004). Additionally, despite the increasing participation of women in graduate education since the 1980s (Walker et al., 2008), Latinas have been and continue to be underrepresented in doctoral programs and the professorate (Myers, 2016). In spite of recent increases in enrollment, Latinas attained just 8.8 percent of the doctoral degrees awarded from 2018-2019 (National Center for Education Statistics, 2020). As Latinas are projected to account for a third of …

Rational Design Of Multifunctional Nanocatalysts For Environmental Remediation And Energy Conversion Technologies, Md Ariful Ahsan

Open Access Theses & Dissertations

The discovery of efficient and sustainable carbon-based nanotechnologies to solve both the scarcity of drinking water and global energy crisis has become a paramount task in the last decades. Owed to the fast population growth and industrialization of the modern society, access to potable water and clean energy technologies is becoming very hard around the globe. Water pollutants have become a serious threat to the environment and ecology because of their toxic nature. Parallelly, the current hydrocarbon-based fuel industries are generating high levels of contamination across the planet, making imperative the development of cleaner energy technologies. In this regard, the …

The Physiological Factors Of Diabetes And Their Effect On The Cognitive And Emotional Functioning In Older Populations: A Secondary Data Analysis, Celeste Anahi Alvidrez

Open Access Theses & Dissertations

Background: The rates of Type 2 Diabetes (T2D) have increased over the past 20 years in all age groups. The physiological factors that underlie T2D could have impact on specific brain pathways that support cognitive and emotional functioning. Aims and Objective: The goal of this study was to examine whether older Mexican American individuals with a history of T2D were more likely to develop later cognitive impairment and/or depression. Hypotheses: It was predicted that elderly participants (mean age at time of interview = 87.87 years) with a history of T2D onset prior to age 65, are more likely to have …

Examination Of The Association Between C - Reactive Protein(Crp) And Covid-19 Infection Severity And Length Of Hospitalization, Abdulahi Aremu Ayanwale

Open Access Theses & Dissertations

Chronic stress can lead to many systemic complications and low-grade systemic inflammation including increased levels of inflammatory cytokines, such as C-reactive protein (CRP). CRP is a marker of systemic inflammation and is associated with depression and perceived stress. Elevations can result in ineffective immune responses, thereby increasing the risk of complications and mortality from infections. Recent evidence suggests that uncontrolled inflammatory responses associated with COVID 19 are a major determinant of disease severity.  The COVID 19 is transmitted from one person to another through droplets from coughing, sneezing, talking, touching droplets on surfaces and contamination by hand-to-mouth routes. The mechanism …

Interval Estimates: How To Make Them More Adequate And How To Use Them In Economic Analysis And Decision Making, Laura Adriana Berrout-Ramos

Open Access Theses & Dissertations

In many real-life situations, we need to make decisions in situations when we do not have full information about the consequences of different decisions. In particular, instead of the exact values of the relevant quantities, we only know lower and upper bounds on these values – i.e., we know an interval that contains the actual (unknown) value. These interval estimates often come from experts. This fact naturally leads to the following important questions: How should we make decisions under such interval uncertainty? How to gauge the quality of the resulting decisions? And if this quality is not sufficient – because …

Level Of Service For Parking Facilities Based On Search Time, Fernie Briones

Open Access Theses & Dissertations

Level of Service (LOS) is a term used by transportation engineers to identify the quality of service of transportation facilities to the public. The Highway Capacity Manual has yet to provide guidance on LOS analysis for parking facilities. Parking search time has been proposed by several researchers as the indicator for the LOS criteria for parking facilities. This thesis investigated the use of search time for LOS analysis for on street and off-street parking facilities. The analysis of LOS for off-street parking focused on the measurement of parking search time. Three search time measurement methods have been proposed: the license …

Drying Of Digested Biosolids For Weight Reduction Prior To Disposal, Juan Manuel Canales

Open Access Theses & Dissertations

Disposal of belt filter pressed digested sludge (known as biosolids) to landfills cost El Paso Water about $1.1 million in the past year. With an increasing population, the amount of influent wastewater to El Paso treatment plants will also increase, resulting in increased biosolids generation and biosolids disposal costs. A method for reducing biosolids transportation cost is biosolids drying.The cost that El Paso Water pays for transporting biosolids to a dedicated landfill facility is based on the weight of the biosolids that are carried. Biosolids collected from the belt filter presses is about fifteen percent solids by weight, with water …

Addressing Security And Privacy Issues By Analyzing Vulnerabilities In Iot Applications, Francsico Javier Candelario Burgoa

Open Access Theses & Dissertations

The Internet of Things (IoT) environment has been expanding rapidly for the past few years into several areas of our lives, from factories, to stores and even into our own homes. All these new devices in our homes make our day-to-day lives easier and more comfortable with less effort on our part, converting our simple houses into smart homes. This increase in inter-connectivity brings multiple benefits including the improvement in energy efficiency in our homes, however it also brings with it some potential dangers since more points of connection mean more potential vulnerabilities in our grid. These vulnerabilities bring security …

Cell Bioprinting: A Novel Approach For Alpha Cell To Beta Cell Transdifferentiation, Atzimba Casas

Open Access Theses & Dissertations

Diabetes is a chronic disease that occurs in the body when the pancreas fails to either produce insulin (TID) or does not effectively use the insulin produced (TIID) and poses further health complications as well as an insurmountable economic impact.[1] Type I diabetes is an autoimmune disease characterized by a deficient amount of insulin production on account of the body’s immune system destroying its own β-cells.[2] Current diabetes treatment methods include the administration of insulin via injections or islet transplantation therapy. However, although both are viable options, they come with limitations that make the managing of this disease difficult. It …

Development Of Metaheuristic Algorithms For The Efficient Allocation Of Power Flow Control Devices, Eduardo Jose Castillo Fatule

Open Access Theses & Dissertations

Modern energy grids have become extremely complex systems, requiring more variable and active flow control. As a remedy to this, Distributed Flexible AC Transmission Systems (D-FACTS) are cost-efficient devices used to mitigate power flow congestion and integrate renewable energies. The objective of this research is then to propose an efficient multiple objective evolutionary algorithm to solve a stochastic model for D-FACTS allocation, which aims to optimize various objectives related to cost, grid health, and environmental impacts. The model was implemented on a modified RTS-96 test system, and the results show that optimally allocating D-FACTS modules using the proposed model can …

"And Some, I Assume, Are Good People:" A Closer Look At Hispanic Immigration And The Code Of The Street, Nicole Cebak

Open Access Theses & Dissertations

Although research shows that increasing neighborhood levels of immigration tend to be associated with lower crime, little attention has been paid to why this is the case-- in essence what variables might help account for, or explain, these findings. Thus, the focus of this study is to explore a cultural explanation, specifically whether adherence to the code of the street helps to explain this relationship. Further, this study is looking to find the differences between immigrant generations as well as recent and established immigrants as it pertains to adherence to the code of the street. Using a random sample of …

In Vitro Investigation Of Tumor Selective Piperidones As Therapeutic Agents Against Leukemia Cancer Cells, Lisett Contreras

Open Access Theses & Dissertations

Cancer is a continuous global health issue. It is the second leading cause of death behind heart disease. Disparities across the emergence of cancer and resulting fatalities raise the importance of researching the disease. Treatments are available for certain types of cancers. However, these are typically accompanied by residual problems including side effects and the possibility for relapse. Some treatments attack all cells, leading to unwarranted side effects that make the possibility of living a comfortable life nearly impossible. Other treatments are specific to certain genetic alterations, making them only useful for a small percentage of patients. Not one treatment …

Effects Of Coated/Uncoated Copper-Based Nanoparticles And Compounds On Rice (Oryza Sativa) And Soybean (Glycine Max) Plants, Chaoyi Deng

Open Access Theses & Dissertations

Engineering nanoparticles (ENPs) have been widely used in industry due to their promising chemical, physical, electrical, magnetic, optical, and electronic properties. Copper-based ENPs are used as gas sensors, catalysts, semiconductors and agricultural products, among others. Because of their antifungal and antibacterial properties, they are used in agriculture as insecticides, herbicides and antifungal agents. Due to their mass production and use, ENPs are likely to be ubiquitous in our in the environment in the near future. In addition, metal nanoparticles are usually coated with organic compounds to enhance the properties of the nanoparticles. Previous studies have shown that copper-based ENPs can …

Global Analysis Of The Hydrologic Sensitivity To Climate Variability, Marisol Dominguez

Open Access Theses & Dissertations

Identifying the regions with greatest changes in their hydrologic behavior under extreme weather events in the 21st century, constitutes a study priority of global impact. Here, we present a global assessment assessing the sensitivity of the world’s water landscapes to climate variability during 2001-2016, using a new metric called the Hydrologic Sensitivity Index (HSi). This equation is based on the well-known Budyko curve that uses annual values of Potential and Actual Evapotranspiration (PET and AET), and Precipitation (P), to assess the hydrologic behavior of a location under a given climatic condition by plotting the Evaporative Index (AET/P) against the Dryness …

Thermodynamic Modeling Of Aqueous Fe-Cu-As-Sb-Bi-H2so4 Solutions And Its Application For Redox Potential Determination In Copper Electrorefining From 25°C To 70°C, Yongteng Dong

Open Access Theses & Dissertations

Impurity elements in copper electrorefining (ER) electrolyte have been becoming a crucial issue on purity of copper cathode. The objective of this doctoral research is to develop a speciation model to understand impurity behavior in aqueous ER solutions.

A thermodynamic model of Fe(II)-Fe(III)-Cu(II)-H2SO4-H2O system is developed and shown to reliably simulate the species distribution in industrial copper electrorefining electrolyte from 25°C to 70°C. The previously developed model of Fe(II)-Fe(III)-H2SO4-H2O system under leaching conditions was first evaluated. It has proved that its applicability can be extended to much higher acid concentration (185 g/L) and high amount of copper (40-50 g/L). Cu(II) …

Validation Of Computational Model Of A Piezoelectric Flow Rate Sensor, Eben Roberto Escobedo

Open Access Theses & Dissertations

This study validates a computational simulation of a piezoelectric cantilever beam undergoing different loads by showing a comparison of its results against theoretical calculations. The objective of the computational model is to simulate the behavior of a beam made of a piezoelectric material which can be used as a flow rate sensor due to the ability of the material to convert a mechanical load into an electrical load. After validating the model, different geometries, material properties and loads can be simulated to observe the different behaviors and bring the possibility of selecting the most convenient options according to the needs …

The Latinx Community, Anti-Black Racism And Forward- Looking Collective Moral Responsibility, Julisa Jazsmine Fernandez-Rivera

Open Access Theses & Dissertations

In the literature on collective responsibility, theorists have utilized different methods in order to argue collective responsibility can be attributed to collectives. Some theorists have referred to Strawsonâ??s account of participant reactive attitudes in order to support their claims that certain collectives can be the appropriate targets of reactive attitudes (2008). According to Strawson (2008), attributing reactive attitudes, such as guilt, praise, hurt feelings, obligation, etc. towards others and ourselves is what constitutes moral responsibility. Though Strawsonâ??s account only focuses on individual responsibility, theorists, such as Deborah Tollefsen and Kay Mathiesen, have extended his account to support their claims about …

Linking Plot And Landscape Level Phenology, Alejandra Flores

Open Access Theses & Dissertations

Plant phenology has become popularize since the 1990s to help understand the effects of climate change on vegetation, it is a way to study the patterns of leaf-out, flowering, and senescing of the life-cycle of the plant. The timing from start of season (SOS) to end-of-season (EOS) of plant leaf-out development has important implication on ecosystem productivity and carbon cycling across ecological scales from individual trees to whole regions. The need for plant phenology studies in dryland are highly anticipated, since they make up 40% of the terrestrial landscape and recently have shown the play an important role in the …

Determination Of Faculty And Staff Parking Permit Prices On University Campuses, Rodrigo Garcia

Open Access Theses & Dissertations

University campuses are the origins and destinations of a variety of trips generated by faculty, staff, students, and visitors. The vast number of trips that are attracted to university campuses result in parking congestion issues. In order to manage campus parking demand, universities establish Transportation and Parking Offices (TPO). This research has developed a two-stage procedure that can be used by TPOs as a tool for determining faculty and staff parking permit prices on university campuses. The first stage of the procedure is the determination of a single campus-wide base price (which may be regarded as the reference price or …

Development Of A Measure Assessing Perceptions Of E-Cigarettes: A Mixed Methods Approach, Dessaray Monique Gorbett

Open Access Theses & Dissertations

Tobacco use is the leading cause of preventable death in the United States (U.S.), killingmore than 480,000 people each year. In recent years, we have seen a steady decline in cigarette smoking but have seen increased alternative tobacco product use (e.g., electronic cigarettes). Positive perceptions of e-cigarettes are associated with increased e-cigarette use (Amrock, Zakhar, Zhou, & Weitzman, 2015; Chen-Sankey & Kong, Choi, 2019; Pokhrel, Fagan, Kehl, & Herzog, 2015; Simmons et al., 2016). However, studies assessing the perceptions of e-cigarettes vary widely and do not adequately capture perceptions of social norms and the addictiveness of e-cigarettes. The current study …

Supercritical Co2 Recompression Closed Brayton Cycle Analysis, Andres Eduardo Gutierrez Hernandez

Open Access Theses & Dissertations

On this research, the results of an analysis made of a Supercritical Carbon Dioxide (sCO2) Recuperated Closed Brayton Cycle (RCBC) done by performing theorical calculations and comparing it to the results obtained with the use of the software ASPEN Plus will be presented. To demonstrate and determine that this software is a useful tool for modeling the proposed type of cycle, a preliminary comparison was made to verify with previous studies found in literature. A comparison and analysis between the possible working fluids and thermal energy sources was also performed to emphasize the decision of using CO2 as the cycle …

Synthesis, Characterization, And Direct-Ink-Writing Of Syntactic Foams, Andrea Irigoyen

Open Access Theses & Dissertations

This project encompasses three different methods to fabricate syntactic foams using a PDMS matrix i.e., hollow spheres inclusion, pore generator leaching by solvent, and emulsion. The foam formation by using polysiloxane hollow spheres is done in a 3-step process. The first step is to create a core of polystyrene following a dispersion polymerization process. The goal for the size of the pore is to monodisperse and have an average diameter of 5-10 μm, so the polystyrene core must be as well within that range. After that, the cores are coated with a polysiloxane shell by following a polymerization by condensation …