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Objective The purpose of the mixed methods study was to compare barriers and facilitators encountered by low-income African American women who engaged in different infant feeding practices. Methods Using the positive deviance approach and modified Integrated Model as theoretical frameworks, the research began with a qualitative study that informed a survey examining intention, skills, and environmental factors differentiating women’s infant feeding practices. Results Twenty-eight and 190 low-income African American adult women participated in focus groups or interviews and a survey, respectively. In the qualitative study, positive deviants, who breastfed for at least four months, seemed to have stronger breastfeeding intentions, self-efficacy and breastfeeding support than other women. In the final multinomial multiple logistic regression, for a one unit increase in the PBC scale of the revised Breastfeeding Attrition Prediction Tool, there was a 50% (OR 1.5[1.3-1.7]) and an 18% (OR 1.18 [1.03-1.3]) increase in the odds of breastfeeding at least three months (positive deviance) compared to only formula-feeding and breastfeeding for less than three months, respectively. Women who did not smoke postpartum were 4.3 [1.5-12.3] and 5.6 [2.1-15.1] times as likely to be positive deviants; women who had C-sections were 3.6 [1.3-9.6] and 2.9 [1.0-7.8] times as likely to be positive deviants compared to only formula-feeding and breastfeeding for less than three months, respectively. Women who ranked WIC full breastfeeding packages as most valuable were 14.9 [4.8-45.5] and 16.1 [5.3-50.0] times as likely to be positive deviants compared to only formula-feeding and breastfeeding for less than three months, respectively. Discussion High breastfeeding self-efficacy was associated with positive deviance, although the qualitative study findings suggested that general self-efficacy may also influence breastfeeding success. The likelihood of not smoking being associated with longer duration of breastfeeding is consistent with previous research. The C-section results may reflect a longer length of hospital stay leading to increased mastery of breastfeeding prior to discharge. Analysis of participants’ valuation of WIC infant feeding incentives led to the suggestion that WIC incentives be re-examined. Further exploration of these findings and subsequent interventions may lead to improved breastfeeding rates among low-income African American women.

Competitive Bidding, Competitive Sealed Proposal, construction management agency, construction management at risk, Design-Build, Design-Build-Bridging, and job order contracting are seven project delivery methods that are commonly used in the state of Texas today. This paper empirically compares the cost, schedule, and change order management performance of these project delivery methods in 2009 Engineering News Record (ENR) Best Construction Projects in Texas, using the data collected from the projects representative of the population. Also information is collected on lessons learned from these projects. The thesis included development of survey instrument, getting approval from Institutional Review Board (IRB), data collection from the industry, statistical analysis and inferences. Based on the data collected, project performances were measured in terms of five identified variables and then plotted in the form of probability distribution curves to understand the characteristics of the target population. Then, the results were grouped into six categories based on project delivery methods used and compared to understand their impacts on these projects. Findings revealed predominant usage of CM at Risk PDM, and better cost and schedule performance of CM at Risk, Design-Build, and Owner customized PDM. Detailed performance metrics, results, interpretations and conclusions are presented.

In this new era of mobile society and information explosion, people are continuously receiving different kinds of information representation at anytime and everywhere, how to quickly learn and absorb different kinds of information to become one¡¦s own knowledge is an important challenge for modern people. Due to the rapid advancement of mobile communication & wireless transmission technology, many scholars in academia were believed that these new technologies will have a great impact on the way of learning in the future. As a matter of fact, by effectively applying short-message services as learning content delivery (LCD) methods, including SMS and MMS, provided by mobile phone system to deliver different learning content representation (LCR) types, Mobile Learning (M-learning) can be implemented accordingly. However, the most important issue is whether M-learning based on these LCD methods and LCR types can really achieve good learning outcomes and be accepted by mobile learners. In this research we will explore the restraint of short-term memory (STM) ability of psychological learning process through technology-mediated learning theory on assessing learning outcomes in M-learning environment. The finding of this study is to match different LCR types with different LCD methods to fit learners¡¦ different STM abilities would cause higher learning outcomes in M-learning environment. Therefore, we suggest that Learners with lower verbal and lower nonverbal STM capacity, the most suitable way to help their learning is just providing them the basic learning materials; learners with higher verbal and lower nonverbal STM capacity, providing them additional written annotations will help them learn better; learners with lower verbal and higher nonverbal STM capacity, providing them additional pictorial annotations will help them learn better; and Learners with higher verbal and higher nonverbal STM capacity, the best way is to cater them both written annotations and pictorial annotations in M-learning environment.

In recent decades, the use of construction manager-at-risk (CMAR) has surged as an innovative construction project delivery method in comparison to traditional competitive bid procurement methods. The conceptual pros and cons of the method are widely accepted throughout the construction industry; however, very little quantitative research exists validating such beliefs. The study presented in this technical paper empirically compares the performance of CMAR to that of the more traditional method of competitive sealed proposal (CSP) in the construction of higher educational facilities. In a study of 33 projects constructed by The Texas A&M University System, 19 procured using CMAR and 14 procured using CSP, observed results show a reduction in schedule growth and change order quantity when using CMAR over CSP. However, additional results show that CSP is more apt to result in decreased project and construction costs than CMAR. Business practices of The Texas A&M University System, statistical significance testing of research data, and practical applications of research findings are included.

Construction Project Procurement Methods (PMs) define the roles, relationships and responsibilities of project team members and the sequence of the activities required to construct or provide a facility. A number of different PMs have evolved over the years, but each is characterised by a different set of features upon which the criteria for selecting the most appropriate method to procure a given project must be based, if successful project performance (PP) is to be ensured. The use of procurement method selection criteria (PMSC) to inform clients’ decision on suitable PMs to adopt remains a recommended good practice in the construction industry. However, project clients in the Libya Construction Industry (LCI), continue to face great challenges when it comes to selecting the most appropriate PM for its projects. The general practice in this industry is largely dominated by a culture of clients’ reliance on their familiarity and experience with a particular method to inform their PM choice, with no consideration of the plethora of other PMs and use of rational approaches to aid in this decision-making. This procurement issue has long been recognised as a major contributory factor to the frequent time and cost overruns often experienced by projects in the LCI. Although the selection of an appropriate PM to procure any given project is known to result in success PP and (and vice versa), very little is known about the nature of this relationship from literature. Having persistently suffered a great deal of project failures over the years, the LCI stands to benefit from detailed knowledge and understanding of how exactly PM choice do actually influence PP. Stimulated by the dearth of this information, this thesis reports on a research investigation into this relationship with the aim of developing a model to explain the criteria functions in contributing to PP and their implications to PM selection practice in Libya. The methodological approach adopted for this research was the mixed method, i.e., using a combination of both quantitative and qualitative approaches. Following a critical review of the extant relevant literature, a number of relevant hypotheses were first formulated, together with a conceptual framework, to establish the theoretical basis underpinning this research, namely the relationship between the selection of PMs (based on PMSC) and PP. The primary data collection stage involved an initial field questionnaire survey aimed at identifying and confirming the key areas of the research inquiry that needs focusing on. This was followed by a semi-structured questionnaire and interview surveys. With the aid of SPSS and Excel, the collected data were analysed, followed by the development of a mathematical model (based on regression) that demonstrate the influence of PMSC on PP. Finally, the model was validated by expert interviews to test for its validity and reliability. The key findings of the research include the identification of DBB and DB selection criteria that contributes to PP. The distinct contribution to knowledge arising from this research includes the development of a regression model to demonstrate this relationship between PMSC and PP. The benefit of these outputs lies not only in the ability of LCI’s clients to make PM selection decisions much faster by virtue of the need for them to only focus on the criteria with significant influence on PP, they are also able to work out, in quantitative terms, the PP outcomes to be expected for each of the method being considered. This latter information would enable clients to compare the PP outcome values expected from their decisions to select DBB and DB, and then be able to conclude which of these two options represents a better procurement strategy for any given project at hand.

The Design/Bid/Build (DBB) delivery method has historically been the most popular and the most effective means of determining the least cost for building a project based upon a set of construction documents. In recent years, however, other project delivery methods, including but limited to Construction Manager/General Contractor (CM/GC) and Design/Build (DB), have slowly taken a share of the construction market away from the DBB delivery method. The choice of delivery method that will produce the best value for an owner in the measurements of efficiency in quality, cost, and timeliness depends upon the type of project and the business culture of the project owner. A unique opportunity for a comparative study was presented by the Meetinghouse Facilities Department (MFD) of the Church of Jesus Christ of Latter-day Saints. The MFD completed over 200 repetitive meetinghouse projects in the U.S. over a five-year period (1999-2003), contracting approximately two-thirds of the projects using a CM/GC delivery method with an attached partnering agreement. The remaining meetinghouses were contracted using a DBB delivery method. A comprehensive comparison was conducted measuring all of the efficiencies created by the selection of delivery method, including short- and long-term costs, direct and indirect costs, construction cycle time, and quality assessment scores. After identifying and then adjusting for several confounding variables in the historical data, the statistical analysis provided evidence that the CM/GC delivery method proved to be the best value for the MFD by producing a total cost savings of over 5.5 percent on the meetinghouse projects when compared to the DBB meetinghouse projects. Construction cycle time was 20% shorter on the CM/GC meetinghouse projects and quality assessment (QA) scores were consistently higher. In regards to a 10-year life cycle repair costs, the CM/GC delivery method produced a higher quality meetinghouse, reducing repair costs by 34% when compared to the DBB meetinghouse projects.

The problem that guided this study was a socio-constructivist view of education via online learning. Based in the extant literature, a deficiency existed that directly correlated online learning closing the academic achievement gap between student populations. In other words, schools invested in technology; however, few empirical data sets existed that established a connection between technology integration and the academic achievement of different student groups. The purpose of this pooled regression analysis study was to determine whether the method of class instruction effected academic achievement gaps between three subpopulations based on gender, race, and SES. Specifically, this study examined whether gender, race, and SES could predict semester grades within and across traditional, blended, and online course instructional methods. The dependent variable for this study was student success in the form of an end-of-unit test grade designed to evaluate student understanding of the curriculum. The independent variables included student gender, ethnicity, and SES. Quantitative data were collected through an analysis of Public Education Information Management System (PEIMS) data and student end-of-unit exam grades. The research suggests one combined interaction, [gender x race] in the traditional learning environment, is statistically significant while several independent interactions are significant. Those independent interactions are TAKS scores, gender, and Socio-economic status. According to the trends in this research, no significant differences exists in academic achievement between African American males and White males enrolled in traditional, blended or online classes. This non-significance is important. As suggested, when all other external factors, in this research, are held constant and the academic playing field is level, male students perform equally within the classroom, also, because no significant differences exists in academic achievement, the quality of instruction from well-trained, highly qualified educators can be an integral factor in closing the achievement gap between African American, low-SES male students.

El propósito de esta investigación consistió en la realización de una propuesta para la implementación de un sistema de gestión para la apropiada supervisión y control de obras de edificación con base en el trabajo colaborativo. El caso de estudio se basó en la construcción de un hotel en el departamento de Cusco. Para ello fue necesario establecer lineamientos para el desarrollo de la propuesta, luego se describió la metodología de gestión y control utilizado por la supervisión de obra. Se realizó la definición de herramientas de gestión y técnicas de control más convenientes para este propósito. Esta investigación se fundamenta en que la mayor parte de proyectos de edificación son ejecutados descuidando el tiempo, costo, alcance y calidad establecidos; debido a procedimientos inadecuados de supervisión y control. Por otro lado, las controversias y relaciones adversas que se producen entre la supervisión de obra, constructor y cliente, son aspectos que pueden causar impactos significativos en las variables mencionadas. Esta propuesta permite que la supervisión de obra pueda efectuar la entrega integrada del proyecto mediante el trabajo colaborativo, utilizando la metodología del Valor Ganado para una adecuada gestión, y aplicando la técnica del Last Planner para el apropiado control y monitoreo del cronograma y de las actividades en ejecución. Finalmente, se concluye que la aplicación de las herramientas y metodologías expuestas, posibilitan a la supervisión de obra gestionar y controlar apropiadamente el alcance, el cronograma, los costos y la correcta ejecución de todos los trabajos que se realizan en obra. / The purpose of this investigation was to make a proposal for the implementation of a management system for the proper supervision and control of works in building construction based on collaborative work. The case study focuses on the construction of a hotel located in the Cusco department. This required the establishment of guidelines for the development of the proposal, and then it was described the management and control methodology used by the site supervisors. The most convenient management tools and control techniques for this purpose were defined. This research is based on the fact that the majority of building projects are executed neglecting the established time, cost, scope and quality due to inadequate supervision and control procedures. On the other hand, controversies and adverse relationships that occur between supervisors, constructor and owner are aspects that can cause significant impacts on the variables mentioned above. This proposal allows the site supervisors to carry out the integrated project delivery through collaborative work, using the Earned Value Methodology for proper management, and applying the Last Planner technique for proper control and monitoring of the progress of the production activities and protect the stipulated deadline in the project's general schedule. Finally, it is concluded that the application of the exposed tools and methodologies enable the site supervisors properly manage and control the scope, schedule, costs and the correct execution of all the works that are carried out on site. / Trabajo de investigación

abstract: The construction industry generates tremendous amounts of data every day. Data can inform practitioners to increase their project performance as well as the quality of the resulting built environment. The data gathered from each stage has unique characteristics, and processing them to the appropriate information is critical. However, it is often difficult to measure the impact of the research across project phases (i.e., planning, design, construction, operation and maintenance, and end-of-life). The goal of this dissertation is to present how industry data can be used to make an impact on construction practices and test a suite of methods to measure the impact of construction research across project phases. The dissertation provides examples of impactful research studies for each project phase to demonstrate the collection and utilization of data generated from each stage and to assess the potential tangible impact on construction industry practices. The completed studies presented both quantitative and qualitative analyses. The first study focuses on the planning phase and provides a practice to improve frond end planning (FEP) implementation by developing the project definition rating index (PDRI) maturity and accuracy total rating system (MATRS). The second study uses earned value management system (EVMS) information from the design and construction phases to support reliable project control and management. The dissertation then provides a third study, this time focusing on the operations phase and comparing the impact of project delivery methods using the international roughness index (IRI). Lastly, the end-of-life or decommissioning phase is tackled through a study that gauges the monetary impact of the circular economy concept applied to reuse construction and demolition (C&D) waste. This dissertation measures the impact of the research according to the knowledge mobilization (KMb) theory, which illustrates the value of the work to the public and to practitioners. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2020