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Scheduling Strategies For Construction Project Managers Toward On Time Delivery, Paul Shamp

Walden Dissertations and Doctoral Studies

Construction management projects involve complex, dynamic environments resulting in uncertainty and risk, compounded by demanding time constraints. Research indicated project managers have struggled to identify best practices for scheduling construction projects via critical path methodologies while searching for tools to increase timely job completions and budget profits. The purpose of this single case study was to explore the strategies that construction project managers used to manage scheduled construction project delivery on time. The constructivist philosophical worldview was used as the framework for this study. Data were collected from semistructured interviews from 7 project managers from 5 different construction companies selected …

Pathways For Improving Nigeria's Procurement System, Donald Osebhawe Areguamen

Walden Dissertations and Doctoral Studies

The manual procurement processes used by some private companies result in increased costs and contract fulfillment delays. The focus of this multiple case study was to explore the strategies procurement managers use to reduce costs and contract fulfillment delays. The population for this study was three procurement managers of private plastics companies located at Maitama, in Abuja, Nigeria. Weiss's theory of change was the conceptual framework for this study. Data collection included semistructured face-to-face interviews and an exploration of company archival financial documents. Data were transcribed, coded, and then validated through member checking, resulting in the emergence of 5 themes: …

Teachers' Experiences With And Perceptions Of Single-Gender Instruction Of African American Students, Kymberli Robinson Chandler

Walden Dissertations and Doctoral Studies

In a large, urban district in western Tennessee, African American students perform considerably lower in math, science, and reading than other districts. Several teachers in western Tennessee are using single-gender instruction as a practice, but little is known about its effectiveness in addressing the needs of African American students. Currently, there is a gap in scholarly and practical understanding of the effects of single-gender classrooms on the academic success of African American students in western Tennessee. This exploratory qualitative case study examined the experiences shared by teachers who use single-gender learning to educate African American students in secondary schools in …

Balancing Career And Family: The Nigerian Woman's Experience, Ngozi Eze

Walden Dissertations and Doctoral Studies

Nigerian women have become more integrated into the workforce, but this integration has led to conflicts between work and family responsibilities. The purpose of this phenomenological study was to explore the lived experiences of Nigerian women regarding challenges and strategies in management and leadership positions in relation to their domestic lives and responsibilities. Liberal and social feminist theory and gendered leadership theory were used as the conceptual framework of the study. The findings of this study came from data obtained from semistructured interviews with 15 Nigerian women in leadership and management positions regarding their perceptions and lived experiences of balancing …

Predicting Success Of Developmental Math Students, Isaac Martinez

Walden Dissertations and Doctoral Studies

Addressing the needs of developmental math students has been one of the most challenging problems in higher education. Administrators at a private university were concerned about poor academic performance of math-deficient students and sought to identify factors that influenced students' successful progression from developmental to college-level coursework. The purpose of this retrospective prediction study was to determine which of 7 variables (enrollment in a college success course, math placement results, frequency of use of the developmental resource center, source of tuition payment, student's age, gender, and race/ethnicity) would be predictive of success in developmental math as defined by a final …

Spiritual Well-Being, Intelligence, And Job Satisfaction Among U.S. Federal Employees, Jesse Earl Moore

Walden Dissertations and Doctoral Studies

Until a slight 1% increase in FY2015, job satisfaction within the United States federal government had decreased between 2010 and 2014. However, even with the slight increase, the job satisfaction level was low which presents a cause for concern for federal government agencies. A growing body of research has indicated that employees are looking for ways to express their spiritual essence in the workplace. Research in this area has suggested that when organizations allow their employees to exercise their spiritual essence in the workplace it not only increases job satisfaction for the employee but also increases job performance. This study …

E-Commerce Adoption By Small And Medium Enterprises In Nigeria, Anthony Obioma Nwosu

Walden Dissertations and Doctoral Studies

The future survival of small and medium enterprises (SMEs) is inextricably linked to their implementation of e-commerce systems. The lack of e-commerce strategies among SME business owners has contributed to a low level of e-commerce adoption by SMEs. The purpose of this multiple case study was to explore the strategies that Nigerian SME business owners used to implement e-commerce systems. The population consisted of retail SMEs in Lagos, Nigeria, that have functional e-commerce systems. The conceptual framework supporting the study was dynamic capabilities framework. Data for the study were derived from semistructured interviews of 4 SME business owners/managers and documentation …

The Impact Of An Online, Mastery, And Project-Based Developmental Math Curriculum On Student Achievement And Attitude, Steven Ray Zollinger

Walden Dissertations and Doctoral Studies

Due to anxiety, low confidence, and inadequate content knowledge, many college students struggle to complete their developmental math coursework. As colleges redesign their programs to address these issues, careful research is imperative to determine the factors that best meet the needs of these struggling students. The purpose of this study was to analyze the impact of one college's redesigned program (integrating online, mastery, and project-based learning) compared with the traditional program. Using Weiner's attribution theory of achievement motivation and emotion as a guide, this mixed methods case study used a quasi-experimental nonequivalent control group design in conjunction with a qualitative …

The Training Deficiency In Corporate America: Training Security Professionals To Protect Sensitive Information, Kenneth Tyrone Johnson

Walden Dissertations and Doctoral Studies

Increased internal and external training approaches are elements senior leaders need to know before creating a training plan for security professionals to protect sensitive information. The purpose of this qualitative case study was to explore training strategies telecommunication industry leaders use to ensure security professionals can protect sensitive information. The population consisted of 3 senior leaders in a large telecommunication company located in Dallas, Texas that has a large footprint of securing sensitive information. The conceptual framework on which this study was based was the security risk planning model. Semistructured interviews and document reviews helped to support the findings of …

Optimization Of The Rf Cavity Heat Load And Trip Rates For Cebaf At 12 Gev, H. Zhang, Y. Roblin, A. Freyberger, G. Krafft, B. Terzić

Physics Faculty Publications

The Continuous Electron Beam Accelerator Facility at JLab has 200 RF cavities in the north linac and the south linac respectively after the 12 GeV upgrade. The purpose of this work is to simultaneously optimize the heat load and the trip rate for the cavities and to reconstruct the pareto-optimal front in a timely manner when some of the cavities are turned down. By choosing an efficient optimizer and strategically creating the initial gradients, the pareto-optimal front for no more than 15 cavities down can be re-established within 20 seconds.

Challenges To Implementing Differentiated Instruction In Middle School Classrooms With Mixed Skill Levels, Kristin Joy Lunsford

Walden Dissertations and Doctoral Studies

Implementing differentiated instruction in classrooms with students who have mixed skill levels often results in teachers facing many challenges. The purpose of this qualitative case study was to explore social studies teachers' perceptions of the challenges they faced when implementing differentiated instruction in classrooms with mixed skill levels and what teachers perceived they needed to help overcome these challenges. This project study was guided by the conceptual frameworks of constructivism from Piaget and Bruner along with the theoretical framework of Vygotsky's zone of proximal development. The research questions focused on the viewpoints of teachers on implementing differentiated instruction in their …

Improving Literacy For Diverse Low Socio-Economic Status Middle School Students, Vivian Fowler Means

Walden Dissertations and Doctoral Studies

In an urban district, Surfside School personnel were concerned that student literacy proficiency levels were low during 2011-2014 and teachers had not been able to close the achievement gap despite a focus on literacy practices and literacy professional development (PD) provided by the district. The purpose of this case study was to explore the perceptions of teachers and administrators in relation to the best instructional practices for increasing self-efficacy when teaching literacy skills and related literacy PD for teachers. Knowles' andragogy theory and Vygotsky's social learning theory formed the theoretical foundation of this study, which hold that PD should provide …

Employing Flight Simulation In The Classroom To Improve The Understanding Of The Fundamentals Of Instruction Among Flight Instructor Applicants, Kenneth P. Byrnes

Journal of Aviation/Aerospace Education & Research

An examination of the gap in the knowledge and understanding of teaching methods that exists in the aviation training industry is examined in this study. Previous research highlights the deficiencies associated with the initial training of Certificated Flight Instructors (CFIs). This study focuses on the training that is required on the fundamentals of instruction, specifically the difficulty associated with training future instructors on how to identify and respond appropriately to human behavior will be addressed. For the purpose of this study a virtual learning environment was created through role play and the use of flight simulation in the classroom. Two …

Relationship Between Budget And Project Success Factors In The Ghanaian Building Construction Sector, Kenneth Kwame Aggor

Walden Dissertations and Doctoral Studies

In developing countries, 60% of project management professionals appear to lack knowledge that timely completion, budget fidelity, and high quality are critical success factors for completion of construction initiatives. Based on the theories of iron triangle, accident causation, scientific management, and strategic management, the purpose of this correlational study was to examine the relationship between project budget and the independent variables of time, quality, safety, environmental impact, and site disputes in the Greater Accra Region of Ghana. One hundred and sixteen project managers, randomly selected from the population of construction professionals in the Greater Accra Region of Ghana, completed the …

The Value Of A Collegiate Far Part 141 Jeopardy-Crew Resource Management (Crm)-Simulation Event, Samuel M. Vance

Journal of Aviation/Aerospace Education & Research

This article explores the viability of using a FAR Part 141 collegiate crew resource management (CRM) flight simulator scenario event as a jeopardy event (a graded, syllabus item) in an upper-level professional pilot curriculum course. Ultimately, the objective is to suggest this approach as a value-added curriculum consideration for other collegiate professional pilot programs. The selection of four CRM criteria to be examined was made by the course professor. Using the four principles, the students assembled the grading rubric for their event. The simulator scenario placed students in airspace, geography and weather dissimilar to that in which they were training …

Forecasting The Air Race Classic: Lessons In Interdisciplinary Aviation Weather Support And Decision-Making, Shawn M. Milrad, Debbie Schaum

Journal of Aviation/Aerospace Education & Research

The Air Race Classic (ARC) is an all-female Visual Flight Rules air race held each June. Embry-Riddle Aeronautical University Daytona Beach (ERAU-DB) has had primarily student race teams participate and frequently place strongly in the ARC since 1996. The ERAU-DB Meteorology Program has provided successful weather support to ERAU-DB race team(s) for the past decade, including as the terminus host institution in 2016. In 2014, the weather support was formalized as a three-credit interdisciplinary summer course, incorporating a mix of aeronautical science (pilot), dispatch, and meteorology students. Using concepts of service and experiential learning, the ARC course has successfully integrated …

Broadening Traditional Aviation Meteorology Education To Support Spaceflight Operations, Thomas A. Guinn, Nicholas J. Stapleton, Katherine A. Winters, Bradley M. Muller, Debbie M. Schaum

Journal of Aviation/Aerospace Education & Research

The purpose of this paper is to examine the expansion of traditional aviation meteorology education necessary to support the growing commercial space-operations industry. While spaceflight meteorological considerations do overlap with those of traditional aviation operations, there are notable differences schools must address for appropriate education and training of both meteorologists and operators. These include knowledge of increased weather sensitivities, space-weather impacts, triggered lightning, triboelectrification, and high-resolution vertical wind-profile analyses. An added challenge in the educational process is the more limited amount of publicly available weather and space-weather products necessary to support spaceflight education. Furthermore, in comparison with traditional aviation meteorology, …

The Relationship Between Nonprofit Organizations And Cloud Adoption Concerns, Dana Haywood

Walden Dissertations and Doctoral Studies

Many leaders of nonprofit organizations (NPOs) in the United States do not have plans to adopt cloud computing. However, the factors accounting for their decisions is not known. This correlational study used the extended unified theory of acceptance and use of technology (UTAUT2) to examine whether performance expectancy, effort expectancy, social influence, facilitating conditions, hedonic motivation, price value, and habit can predict behavioral intention (BI) and use behavior (UB) of NPO information technology (IT) managers towards adopting cloud computing within the Phoenix metropolitan area of Arizona of the U.S. An existing UTAUT2 survey instrument was used with a sample of …

Exploring Security, Privacy, And Reliability Strategies To Enable The Adoption Of Iot, Daud Alyas Kamin

Walden Dissertations and Doctoral Studies

The Internet of things (IoT) is a technology that will enable machine-to-machine communication and eventually set the stage for self-driving cars, smart cities, and remote care for patients. However, some barriers that organizations face prevent them from the adoption of IoT. The purpose of this qualitative exploratory case study was to explore strategies that organization information technology (IT) leaders use for security, privacy, and reliability to enable the adoption of IoT devices. The study population included organization IT leaders who had knowledge or perceptions of security, privacy, and reliability strategies to adopt IoT at an organization in the eastern region …

Small To Medium Enterprise Succession Planning: Millennial Employee Development, Mark Tarmann Jr.

Walden Dissertations and Doctoral Studies

Increased mobility and a growing presence in the workforce by millennial employees are pushing sustainability to the forefront of concerns for business leaders. Especially for small to medium enterprises (SMEs) with limited human capital resources and no formal succession plans. Thus, increasing the need for insight on millennial employee development to mitigate voluntary turnover. The purpose of this multiple case study was to explore successful millennial employee developmental strategies employed by 3 SMEs leaders in southern New Jersey. These SMEs leaders were the ideal population with millennial employees with 3 or more years of employment and not solely family-run organizations. …

Elementary Teachers' Perceptions Of Practices And Professional Development For Differentiating Mathematics Instruction, Sandra Mujagic Varajic

Walden Dissertations and Doctoral Studies

Teachers and administrators in a Title I elementary school in a southeastern state are concerned that there has been a trend over the past 3 years of declining standardized assessment scores in mathematics for students in Grades 3, 4, and 5. The purpose of this qualitative case study was to explore teachers' perceptions of practices, and professional development (PD) for differentiating mathematics instruction. This study was grounded in the conceptual framework of Vygotsky's zone of proximal development and Tomlinson's differentiated instruction (DI). Purposeful sampling was used to select 8 teachers and 1 mathematics coach, who worked with students in Grades …

Measurement Of Two-Photon Exchange Effect By Comparing Elastic E ± P Cross Sections, D. Rimal, D. Adikaram, B. A. Raue, L. B. Weinstein, J. Arrington, W. K. Brooks, M. Ungaro, K. P. Adhikari, A. V. Afanasev, Z. Akbar

Physics Faculty Publications

Background: The electromagnetic form factors of the proton measured by unpolarized and polarized electron scattering experiments show a significant disagreement that grows with the squared four-momentum transfer (Q²) . Calculations have shown that the two measurements can be largely reconciled by accounting for the contributions of two-photon exchange (TPE). TPE effects are not typically included in the standard set of radiative corrections since theoretical calculations of the TPE effects are highly model dependent, and, until recently, no direct evidence of significant TPE effects has been observed.

Purpose: We measured the ratio of positron-proton to electron-proton elastic-scattering cross …

Understanding Of Phenolic Compound Retention Mechanisms On Pes-Uf Membrane, Amine Mnif, Meral Mouelhi, Bechir Hamrouni

Turkish Journal of Chemistry

Ultrafiltration (UF) is investigated as a possible alternative to remove organic compounds from aqueous synthetic solution. This paper presents a comprehensive study towards a better understanding of phenolic compound retention mechanisms during UF processes. Thus, removal of phenol and resorcinol was studied using a polyethersulfone ultrafiltration (PES-UF) membrane. The influence of main operating conditions (feed concentration, transmembrane pressure, and pH) on the retention was evaluated. Membrane--solute interactions were found to play an important role during the process, suggesting the adsorption of the target compounds on the PES-UF membrane. The level of adsorption was consequently evaluated by measuring the quantity of …

Synthesis Of Pds/Zns--Cds-Type Photocatalysts Using Zns As Sulphide Source, Radu Banica, Petrica Linul, Cristina Mosoarca

Turkish Journal of Chemistry

In this work, a new method for the growth of large CdS crystals into PdS/ZnS--CdS-type photocatalysts is presented. In order to accomplish this, in the first stage zinc sulphide was synthesised and hydrothermally crystallised. In the second stage, after PdS decoration, the recrystallised zinc sulphide was utilised as sulphur source for the synthesis of PdS/ZnS--CdS-type photocatalysts. The photocatalysts were characterised by X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectroscopy, and diffuse reflectance spectroscopy. In the third stage magnetic polymer supports were manufactured and loaded with photocatalyst. Finally photocatalysis experiments under blue light illumination were conducted for the hydrogen evolution …

Ultrasound-Assisted Surfactant/Ionic Liquid Aqueous Two-Phase System Extraction Prior To High Performance Liquid Chromatography For The Determination Of Tetracyclines In Milk And Honey Samples, Hayri̇ye Mi̇ne Antep, Taşkin Mumcu, Kami̇l Bostanci, Serap Seyhan Bozkurt, Melek Merdi̇van

Turkish Journal of Chemistry

In this work, an ultrasonic-assisted surfactant/ionic liquid aqueous two-phase system (ATPS) extraction method was developed to extract six tetracycline antibiotics from food samples before their chromatographic determination using high performance liquid chromatography. The ATPS was formed with 1-allyl-3-methyl-imidazolium bromide, Triton X-100, and dipotassium hydrogen phosphate. The parameters including type and amount of surfactant, ionic liquid and salt, pH of sample solution, and sonication time were optimized. Under the optimized conditions, linear calibration curves of the six tetracyclines were obtained in the range of 10--500 $\mu $g L$^{-1}$ with $>$ r$^{2} =$ 0.990 (n $=$ 9). The proposed green analytical …

Spectrophotometric Detection Of Rhodamine B In Tap Water, Lipstick, Rouge, And Nail Polish Samples After Supramolecular Solvent Microextraction, Nebi̇ye Özkantar, Mustafa Soylak, Mustafa Tüzen

Turkish Journal of Chemistry

A simple and sensitive supramolecular solvent-based dispersive liquid--liquid microextraction method was described for the separation/preconcentration and spectrophotometric detection of rhodamine B. The microextraction method, which was realized at ambient temperature for the detection of rhodamine B, was carried out by using supramolecular solvents such as tetrahydrofuran and decanoic acid. The method was based on analyses of rhodamine B by using UV-Vis spectrophotometry at 558 nm. The influences of some parameters such as pH, sample volume, eluent solutions, centrifugation time, and ultrasonic bath time were optimized. The effects of various matrix ions were also investigated. Moreover, the limit of detection and …

A Promising Materials Approach To Combatting Renal Hyperphosphatemia: Fe(Ii)-Montmorillonites, Xiaotong Yuan, Dawei Qin, Min Qiao, Gang Liu, Hongxin Li, Xia Niu

Turkish Journal of Chemistry

The objective of the current effort was to determine the efficacy of Fe(II)-montmorillonite (Fe(II)-MMT) as an adjuvant for specific targeted adsorption of phosphate. Specifically, Fe(II)-MMT was studied to combat hyperphosphatemia and anemia arising from chronic renal failure. The adsorption of phosphate over time, pH, and initial concentration was studied. The systems were characterized by X-ray diffraction (XRD), Raman, and zeta potential. The experimental results demonstrated the adsorption time was set to 140 min to achieve maximum adsorption efficiency. It was thus found that the maximum adsorption was at pH 3.0. In addition, it reached equilibrium when the initial phosphate concentration …

Henderson News 5.2, Bede Mitchell, Dontonio Thomas

Library Publications (1999-2023)

• Remnant Trust Exhibit and Lectures
• New faculty: Billy glasco
• Retirement: Robert Fernekes
• Retirement: Jocelyn Poole

Recent Advances In Thymidine Phosphorylase Inhibitors: Syntheses And Prospective Medicinal Applications, Muhammad Aamir Sajid, Zulfiqar Ali Khan, Sohail Anjum Shahzad, Syed Ali̇ Raza Naqvi, Muhammad Usman, Ahsan Iqbal

Turkish Journal of Chemistry

This review paper covers recent advances in the synthetic strategies for novel TPase inhibitors and their potential medicinal applications over the last few decades. A brief introduction covering the structural aspects of TPase inhibitors is also included to facilitate understanding of diverse approaches to monitor the design of new inhibitors. TPase is an essential enzyme and its inhibition is a potential target in the development of anticancer drugs.

Supramolecular Solvent Microextraction Of Uranium At Trace Levels From Water And Soil Samples, Mansoor Khan, Erkan Yilmaz, Mustafa Soylak

Turkish Journal of Chemistry

A supramolecular solvent microextraction procedure was established for the separation/preconcentration of uranium(VI) (U(VI)) prior to its determination by UV-Vis spectrophotometry. 1-(2-Pyridylazo)-2-naphthol (PAN) was used to form a red chelate (U-PAN) with U(VI) at pH 10. U-PAN was extracted by undecanol in tetrahydrofuran. All the parameters that affect extraction efficiency like solution pH, amount of ligand, type and volume of supramolecular solvent, sample volume, and diverse ion effect were optimized. The preconcentration factor was 17. The detection limit was 0.31 $\mu $g L$^{-1}$. The method was validated using GBW07424 (GSS-10 certified reference material). Microextraction was also applied to water and soil …