Adapting Critical Chain Project Management to Army Engineer Construction Projects

For decades, Army Engineers have utilized the systems of the Critical Path Method (CPM) and multi-level Gantt chart planning system for its construction projects. While these methods are well accepted, they are not without their flaws. Research and literature in project management has given weight to several viable alternative options to planning projects. One such option, Critical Chain Project Management (CCPM), was developed to address the flaws of CPM by offering a holistic approach to project management based on strict resource control and the use of time buffers. This method attempts to eliminate multitasking and procrastination that can plague efficiency and offer managers more flexibly on tasks that otherwise had no leeway. CCPM may give project managers more flexibility and control while at the same time shortening the overall length of a project, saving time and money. The purpose of this thesis was to address the time saving and resource management benefits of utilizing CCPM over CPM and analyze the viability of those benefits being applied to U.S. Army Corps of Engineers construction project planning. Through the use of surveys of Army Engineer project supervisors, several key factors that cause delays because of CPM were identified and rated. The validity of CCPM based solutions to the same issues were also assessed by Army project supervisors in the survey. Analysis of the survey results indicated that CCPM may offer solutions to major issues that Army project supervisors face

Exchange-correlation orbital functionals in current-density-functional theory: Application to a quantum dot in magnetic fields

The description of interacting many-electron systems in external magnetic fields is considered in the framework of the optimized effective potential method extended to current-spin-density functional theory. As a case study, a two-dimensional quantum dot in external magnetic fields is investigated. Excellent agreement with quantum Monte Carlo results is obtained when self-interaction corrected correlation energies from the standard local spin-density approximation are added to exact-exchange results. Full self-consistency within the complete current-spin-density-functional framework is found to be of minor importance.Comment: 5 pages, 2 figures, submitted to PR

Large Discussion Groups’ Impact on Engagement and Community

To address the solitary nature of online learning, asynchronous micro discussion tools can be implemented to enrich students’ learning experiences by encouraging interaction among students, nurturing social presence, and facilitating community development. Students’ experiences using an asynchronous micro discussion tool in online learning were investigated, with a focus on engagement in learning with peers, sense of community, and technology’s effectiveness. Survey data was analyzed from two sections of an online introductory course from 458 postsecondary university students. As part of the course evaluation, students were asked to participate in three, intentionally designed discussions using an asynchronous micro discussion tool. In each instance, the discussion topic was tightly linked to course content, promoting collaborative, reflective learning. Results indicated that while students felt that learning through asynchronous micro discussions was effective, they did not feel a strong sense of community using this method. However, students who experienced increased engagement also reported having a better understanding of the course material, fewer technological issues, and felt a stronger peer-to-peer connection. Importantly, collaborative learning that increases engagement does not appear to be negatively influenced by large group size in higher education. Given the prevalence of the online learning environment this is valuable course design information

Effectiveness of Guests in Large Enrolment Online Courses as an Instructional Strategy

This paper introduces preliminary findings of an evaluation of the design-effectiveness of the guest instructional strategy focusing on guest speakers' effectiveness for learning (Costello, 2012; 2014a, b) and enhancing social presence (Short, Williams & Christie, 1976) in a networked learning course. HKR 1000, Fitness and Wellness, is an introductory online course widely subscribed by students at Memorial University, seeing about 1000 yearly registrations. In each of the three (fall, winter, spring) thirteen-week semesters, sections of 80 students are virtually combined into one course shell within the learning management system (LMS), Brightspace, formerly Desire2Learn (D2L). In the spring and fall 2015 semesters the design-effectiveness of the guest instructional strategy was evaluated based on students' perspectives (N=688). Effectiveness was determined by whether guests impacted student learning, related to course content, provided real life relevance, and fostered social presence. While large enrolments in online courses are not typical or favoured, it is possible to effectively design instructional strategies that use social learning (Rohr & Costello, 2015) to enhance learning and social presence. Content for HKR 1000 focuses on key topics for living healthy, active lifestyles, including basic principles of physical fitness, cardiorespiratory endurance, muscular strength and endurance, flexibility, body composition, nutrition, stress and weight management. To further highlight the link between real world experiences and course content, guest video presentations and discussions were included in the online course environment. Guests bring a unique perspective to a learning community as an integral, authentic resource impacting student success both in their learning and their professions (Costello, 2014b, Finkelstein, 2006). The use of guests as an instructional strategy (Costello, 2014a, Lowenthal, 2009) also served as a means to increase social presence in the course. The guests each appeared for a week during the semester, their topics being tightly linked to specific course content. Each had a unique, relevant area of expertise to share and provided a short 2-4 minute video clip and engaged in discussion with the students in the LMS discussion forum for the remainder of their respective week. An anonymous survey was administered in the learning management system to collect student feedback on these matters. Questions explored whether the students viewed the videos, posted questions, and read the discussion forums. In addition students were asked to reflect on the approachableness and warmth of each guest. Results indicate a positive guest impact on student learning, provision of real life relevance and enhancement of social presence

Correlation potentials for molecular bond dissociation within the self-consistent random phase approximation

Self-consistent correlation potentials for H$_2$ and LiH for various inter-atomic separations are obtained within the random phase approximation (RPA) of density functional theory. The RPA correlation potential shows a peak at the bond midpoint, which is an exact feature of the true correlation potential, but lacks another exact feature: the step important to preserve integer charge on the atomic fragments in the dissociation limit. An analysis of the RPA energy functional in terms of fractional charge is given which confirms these observations. We find that the RPA misses the derivative discontinuity at odd integer particle numbers but explicitly eliminates the fractional spin error in the exact-exchange functional. The latter finding explains the accurate total energy in the dissociation limit.Comment: 9 pages, 10 figure

Forest and Prairie in Three Northwestern Indiana Counties

The modifying influence of civilized man on natural vegetation is so rapid and so extensive that it becomes a difficult problem after a century or more to picture the original vegetation cover. The task is still more difficult when one attempts to express the vegetation in quantitative terms. Today the taxonomists scour the railway right-of-way for specimens of prairie plants for the prairie itself with its plant sociology has vanished. We will never be able adequately to reconstruct this vegetation complex, and we can only with difficulty draw its former boundary. Even though the surveyors of the original United States land survey, whose records form the basis of this study, made copious notes on prairie areas, it is likely that sedge-meadow type of vegetation was included under their classification of wet prairie. If the term actually described areas dominated by typical prairie grasses, then Indiana at that time had wet prairie, dry prairie and a transition type of prairie and forest association, park-like in nature, which might be called oak openings

Relativistic nucleon optical potentials with isospin dependence in Dirac Brueckner Hartree-Fock approach

The relativistic optical model potential (OMP) for nucleon-nucleus scattering is investigated in the framework of Dirac-Brueckner-Hartree-Fock (DBHF) approach using the Bonn-B One-Boson- Exchange potential for the bare nucleon-nucleon interaction. Both real and imaginary parts of isospin-dependent nucleon self-energies in nuclear medium are derived from the DBHF approach based on the projection techniques within the subtracted T -matrix representation. The Dirac potentials as well as the corresponding Schrodinger equivalent potentials are evaluated. An improved local density approximation is employed in this analysis, where a range parameter is included to account for a finite-range correction of the nucleon-nucleon interaction. As an example the total cross sections, differential elastic scattering cross sections, analyzing powers for n, p + 27Al at incident energy 100 keV < E < 250 MeV are calculated. The results derived from this microscopic approach of the OMP are compared to the experimental data, as well as the results obtained with a phenomenological OMP. A good agreement between the theoretical results and the measurements can be achieved for all incident energies using a constant value for the range parameter.Comment: 10 pages, 16 figure

Probing the pairing symmetry in the over-doped Fe-based superconductor Ba_0.35Rb_0.65Fe_2As_2 as a function of hydrostatic pressure

We report muon spin rotation experiments on the magnetic penetration depth lambda and the temperature dependence of lambda^{-2} in the over-doped Fe-based high-temperature superconductor (Fe-HTS) Ba_{1-x}Rb_ xFe_2As_2 (x = 0.65) studied at ambient and under hydrostatic pressures up to p = 2.3 GPa. We find that in this system lambda^{-2}(T) is best described by d-wave scenario. This is in contrast to the case of the optimally doped x = 0.35 system which is known to be a nodeless s^{+-}-wave superconductor. This suggests that the doping induces the change of the pairing symmetry from s^{+-} to d-wave in Ba_{1-x}Rb_{x}Fe_{2}As_{2}. In addition, we find that the d-wave order parameter is robust against pressure, suggesting that d is the common and dominant pairing symmetry in over-doped Ba_{1-x}Rb_{x}Fe_{2}As_{2}. Application of pressure of p = 2.3 GPa causes a decrease of lambda(0) by less than 5 %, while at optimal doping x = 0.35 a significant decrease of lambda(0) was reported. The superconducting transition temperature T_c as well as the gap to T_c ratio 2Delta/k_BT_c show only a modest decrease with pressure. By combining the present data with those previously obtained for optimally doped system x = 0.35 and for the end member x = 1 we conclude that the SC gap symmetry as well as the pressure effects on the SC quantities strongly depend on the Rb doping level. These results are discussed in the light of the putative Lifshitz transition, i.e., a disappearance of the electron pockets in the Fermi surface of Ba_{1-x}Rb_{x}Fe_{2}As_{2} upon hole doping.Comment: Accepted for publication in Physical Review