Ground source heat pump (GSHP) uses earth’s heat to heat or cool space. Absorbing heat from earth or rejecting heat to the earth, changes soil’s constant temperature over the multiple years. In this report we have studied about Soil temperature change over multiple years due to Ground loop heat exchanger (GLHE) for Zero Energy Research Laboratory (ZØE) which is located in Discovery Park, University of North Texas, Denton, TX. We did 2D thermal analysis GLHP at particular Depth. For simulation we have used ANSYS workbench for pre-processing and FLUENT ANYS as solver. TAC Vista is software that monitors and controls various systems in ZØE. It also monitors temperature of water inlet/outlet of GLHE. For Monitoring Ground temperatures at various depths we have thermocouples installed till 8ft from earth surface, these temperatures are measured using LabVIEW. From TAC Vista and LabVIEW Reading’s we have studied five parameters in this report using FLUENT ANSYS, they are; (1) Effect of Time on soil Temperature change over Multi-years, (2) Effect of Load on soil temperature change over Multi-years, (3) Effect of Depth on soil temperature change over Multi-years, (4) Effect of Doubling ΔT of inlet and outlet of GLHE on soil temperature change over multi-years and (5) Effect on soil temperature change for same ZØE Laboratory, if it’s in Miami, Florida. For studying effect of time on soil temperature change for multi-years, we have varied heating and cooling seasons. We have four cases they are Case A: GSHP always “ON” (1) 7 months cooling and 5 month cooling and (2) 257 days are cooling and 108 days heating. Case B: GSHP “OFF” for 2 months (1) 7 months cooling and 3 months heating and (2) 6 months cooling and 4 month heating. For Studying Effect of Load on soil temperature change over multi-years, we have considered maximum temperature difference between inlet and outlet for heating and cooling season for simulation. For studying effect of doubling ΔT of inlet and outlet of GLHE, we have doubled the temperature difference between inlet and outlet of GLHP. There will be soil temperature change over year at various depths. For studying Effect of Depth on soil temperature change for multi-years, we have consider 5 depths, they are 4ft, 6ft, 8ft, 110ft and 220ft. The Densities of soil are known from site survey report of ZØE GSHP manufacturers till depth of 13ft. For studying effect of soil temperature over multi-years for same ZØE in Miami, Florida, we have considered equivalent cooling and heating season from weather data for past one year and assuming same number of days of cooling and heating for next 20 years we have simulated for soil temperature change.

The three-dimensional perovskites are known for their wide range of interesting properties including spectral tunability, charge carrier mobility, solution-based synthesis and many others. Such properties make them good candidates for photovoltaics and photodetectors. Low-dimensional perovskites, on the other hand, are good as light emitters due to the quantum confinement originating from their nanoparticle size. Another class of low-dimensional perovskites, also called low-dimensional-networked perovskites (L-DN), is recently reemerging. Those interesting materials combine the advantages of the nanocrystals and the stability of the bulk. For example, zero-dimensional-networked perovskite (0-DN), a special class of perovskites and the focus of this work, consists of building blocks of isolated lead-halide octahedra that could be synthesized into mm-size single crystal without losing their confinement. This thesis focuses on the synthesis and investigation of the optical properties of the 0-DN perovskites through experimental, theoretical and computational tools. The recent discovery of the retrograde solubility of the perovskites family (ABX3), the basis of the inverse temperature crystallization (ITC), inspired the reinvestigation of the low-dimensional-networked perovskites. The results of the optical characterization showed that the absorption and the corresponding PL spectra were successfully tuned to cover the visible spectrum from 410 nm for Cs4PbCl6, to 520 nm and 700 m for Cs4PbBr6 and Cs4PbI6, respectively. Interestingly, the exciton binding energies (Eb) of the 0-DNs were found to be in the order of few hundred meV(s), at least five times larger than their three-dimensional counterpart. Such high Eb is coupled with a few nanoseconds lifetime and ultimately yielded a high photoluminesce quantum yield (PLQY). In fact, the PLQY of Cs4PbBr6 powder showed a record of 45%, setting a new benchmark for solid-state luminescent perovskites. Computational methods were used to calculate the bandgap and study the corresponding excitonic behavior. However, the unexpected mismatch between the calculated and experimental bandgaps questions the origin of the high luminescence, which to date, remains an area of scientific debate that needs further study. Until then, the high PLQY, together with the spectral tunability, insensitivity to particle size and stability all offer a new avenue for more sustainability in light-emitting materials

0 / SPK / specialcollections@tulane.edu

Computer network administrators need advanced tools to configure network devices. For this purpose, the NETCONF protocol and the YANG modeling language were developed. The aim of this thesis is to implement the Zero Touch mechanism that serves the initial configuration of the NETCONF server. This mechanism will be integrated into the sysrepo datastore.

With the rise of the Internet of Things, more and more devices are being connected to the internet, driving up the demand for wireless connectivity. In addition to advancing the current RF technology, optical communication, specifically IR wireless communication, is a competitive option to help offload some of the wireless demand. However, one of the crucial components for an effective IR system is the ability to quickly and controllably steer the IR light around a room, providing data as a device moves. This thesis focuses on tip-tilt MEMS micromirrors for indoor optical wireless communication (OWC), specifically two key aspects, (1) design and (2) controls. We discuss two unique tip-tilt mirror designs for indoor OWC. The first is an electrothermal varifocal mirror capable of changing its shape, and therefore the shape of the beam in real time. The mirror's radius of curvature can range between -0.48 mm and 20.5 mm, focusing light from a bare fiber from a half-angle divergence of 5° to 0.18° The second mirror uses electromagnetic actuation to achieve a large quasi-static angular range capable of ±60° mechanical ±120° optical) about two rotation axes. In other words, with a laser beam focused on the mirror from the zenith, the device could direct the beam anywhere in a hemisphere. In addition to the device design, we discuss a series of control techniques that can improve the step-and-settle response time of a MEMS device by orders of magnitude compared to a traditional step input. For example, this technique is used to settle the above magnet mirror within 4.5 ms, a factor of 300 improvement over the 1.35 s settling time of a traditional step input. These techniques can be used in conjunction with pulse width modulation (PWM) to provide a fast, low-cost controls solution with no loss in performance. Designing mirrors with these types of controls in mind will not only benefit OWC but enable new applications as well.

The purpose of this qualitative document analysis research study was to explore how public high schools in California create local unexcused absence and truancy policies in similar and different ways. The study used Lipsky’s “street-level bureaucracy” and the American Psychological Association Zero Tolerance Task Force’s definition of “zero tolerance policies” in the conceptual framework. Forty-two California public high school handbooks were qualitatively coded and analyzed for the extent to which their disciplinary responses to unexcused absences were aligned with the ideals of zero tolerance. Schools were purposefully selected to maximize contrasts between specific student demographic groups and school enrollment sizes. The demographic groups included schools with: high/low minoritized enrollment, high/low ELL enrollment, and high/low enrollment of students with low socioeconomic statuses. School truancy rates were also included as a descriptor in the analysis. The findings from this study revealed that schools with higher enrollment sizes tended to employ disciplinary responses to unexcused absences that were more aligned with zero tolerance policies than schools with lower enrollment sizes. Schools with low minoritized enrollment, low ELL enrollment, and low levels of poverty also tended to rely more heavily on zero tolerance responses to unexcused absences. Truancy rates tended to decrease as zero tolerance policies increased, although there was no evidence that the policies themselves were responsible for the increase in attendance. Few examples of comprehensive truancy prevention and intervention programs were found in this study. Schools that did not rely on zero tolerance did not tend to have innovative programs to address the underlying issues of student truancy. The study ends with a discussion on the ways in which strict zero tolerance policies at schools with most students in the social majority are likely perpetuating the issue of students from marginalized backgrounds being disciplined at higher rates than other students. There is also discussion regarding the fact that harsh zero tolerance policies have the potential to put students who need the most help in a further disadvantaged position.

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The purpose of this basic qualitative study was to gather data on the training that was provided for school staff regarding the implementation of the restorative justice program. This study also investigated elementary school administrators' perceptions after implementation of a restorative justice program and its impact on student discipline in one rural Virginia school division. In the Commonwealth of Virginia, 22% of students are African American, but they make up 54% of students who have been suspended from school for the 2018-2019 school year (VDOE, 2021). School divisions can benefit from this qualitative study to address discipline disproportionality by implementing restorative justice practices. Findings indicated restorative justice had an impact in reducing student discipline issues and enhancing teacher-student relationships, as reported by participants. However, challenges like teacher buy-in were also identified. Considerations for successful implementation include restorative justice training for school administrators and teachers, with an emphasis on proactive practices such as classroom circles. In addition, improved communication between students and teachers was noted as a positive outcome of this restorative justice program. Elementary school administrators should provide support for restorative justice practices to strengthen teacher-student relationships. They should also gather discipline data before and after implementing these practices to assess their impact. Consistent training for all staff within a school division is crucial, and administrators should involve staff in the implementation process to foster buy-in. Findings from this study indicate more research is needed on the impact restorative justice practices has on student discipline in K-12 public schools. / Doctor of Education / The purpose of this basic qualitative study was to gather data on the training that was provided for school staff regarding the implementation of the restorative justice program. This study also investigated elementary school administrators' perceptions after implementation of a restorative justice program and its impact on student discipline in one rural Virginia school division. This qualitative study investigated the viewpoints of elementary school administrators following the implementation of a restorative justice program, examining how it influenced student discipline. Findings indicated restorative justice helped reduce student discipline issues and improved teacher-student relationships. However, challenges like teacher buy-in were also identified. To implement restorative justice practices successfully, training for administrators and staff is important, focusing on proactive practices like classroom circles. The program also led to better communication between students and teachers. School administrators should support these practices, collect and analyze discipline data, ensure consistent training for all staff, and involve them in the process to gain their support. Findings from this study indicate more research is needed on the impact restorative justice practices has on student discipline in K-12 public schools.

Many nitroaromatic compounds (NACs) are considered toxic and potential carcinogens. The purpose of this study was to develop an integrated reductive/oxidative process for treating NAC contaminated waters. The process consists of the combination of zero-valent manganese or iron and a hydroxyl radical based treatment technique. Corrosion promoters were added to the contaminated water to minimize passivation of the metallic species. Water contaminated with 2,4-dinitrotoluen (DNT) was treated with the integrated process using a recirculating batch reactor. It was demonstrated that addition of corrosion promoters to the contaminated water enhanced the rate of reaction of 2,4-DNT with zero-valent iron or manganese. Results showed that iron provided greater reduction of 2,4-DNT than manganese. Chemical oxidation was used to mineralize the reduction products. The degree of mineralization was measured analyzing the samples for total organic carbon and nitrates. A proposed reaction and corrosion mechanisms and rate expressions were developed during the course of the study.