Nanosatellite fabrication and analysis

The advancements in technologies used in the aerospace industry have allowed universities to experiment with and develop small-scale satellites. Universities are taking advantage of the relatively low development costs of nanosatellite programs to give students experience in the field of spacecraft design. The purpose of Santa Clara University\u27s team, Nanosatellite Fabrication and Analysis, is to create a process to expedite the design, analysis, and fabrication phase of nanosatellite structures for students working on future satellite missions. The objective is to design four baseline nanosatellite structures to accommodate a range of potential missions where the designs are simple enough to be completely fabricated by students utilizing only the tools found in the Santa Clara University\u27s machine lab. Finite element analysis is conducted to ensure the designs meet NASA standards for natural frequency and that it can survive the forces it is subjected to during a launch. SatTherm, an easy to use thermal analysis tool for small spacecrafts, was used to conduct initial thermal simulations of the nanosatellite to determine the type of thermal components that will work for future missions. The success of team Nanosatellite Fabrication and Analysis proves that students can fabricate the structural frame of a nanosatellite using only the tools available in SCU\u27s machine lab

Fully Constrained Majorana Neutrino Mass Matrices Using Σ(72×3)\Sigma(72\times 3)

In 2002, two neutrino mixing ansatze having trimaximally-mixed middle ($\nu_2$) columns, namely tri-chi-maximal mixing ($\text{T}\chi\text{M}$) and tri-phi-maximal mixing ($\text{T}\phi\text{M}$), were proposed. In 2012, it was shown that $\text{T}\chi\text{M}$ with $\chi=\pm \frac{\pi}{16}$ as well as $\text{T}\phi\text{M}$ with $\phi = \pm \frac{\pi}{16}$ leads to the solution, $\sin^2 \theta_{13} = \frac{2}{3} \sin^2 \frac{\pi}{16}$, consistent with the latest measurements of the reactor mixing angle, $\theta_{13}$. To obtain $\text{T}\chi\text{M}_{(\chi=\pm \frac{\pi}{16})}$ and $\text{T}\phi\text{M}_{(\phi=\pm \frac{\pi}{16})}$, the type~I see-saw framework with fully constrained Majorana neutrino mass matrices was utilised. These mass matrices also resulted in the neutrino mass ratios, $m_1:m_2:m_3=\frac{\left(2+\sqrt{2}\right)}{1+\sqrt{2(2+\sqrt{2})}}:1:\frac{\left(2+\sqrt{2}\right)}{-1+\sqrt{2(2+\sqrt{2})}}$. In this paper we construct a flavour model based on the discrete group $\Sigma(72\times 3)$ and obtain the aforementioned results. A Majorana neutrino mass matrix (a symmetric $3\times 3$ matrix with 6 complex degrees of freedom) is conveniently mapped into a flavon field transforming as the complex 6 dimensional representation of $\Sigma(72\times 3)$. Specific vacuum alignments of the flavons are used to arrive at the desired mass matrices.Comment: 20 pages, 1 figure. arXiv admin note: substantial text overlap with arXiv:1402.085

Constraints on Electroweak Effective Operators at One Loop

We derive bounds on nine dimension-six operators involving electroweak gauge bosons and the Higgs boson from precision electroweak data. Four of these operators contribute at tree level, and five contribute only at one loop. Using the full power of effective field theory, we show that the bounds on the five loop-level operators are much weaker than previously claimed, and thus much weaker than bounds from tree-level processes at high-energy colliders.Comment: 15 page

Deviations from Tribimaximal Neutrino Mixing using a Model with Δ(27)\Delta(27) Symmetry

We present a model of neutrino mixing based on the flavour group $\Delta(27)$ in order to account for the observation of a non-zero reactor mixing angle ($\theta_{13}$). The model provides a common flavour structure for the charged-lepton and the neutrino sectors, giving their mass matrices a `circulant-plus-diagonal' form. Mass matrices of this form readily lead to mixing patterns with realistic deviations from tribimaximal mixing, including non-zero $\theta_{13}$. With the parameters constrained by existing measurements, our model predicts an inverted neutrino mass hierarchy. We obtain two distinct sets of solutions in which the atmospheric mixing angle lies in the first and the second octants. The first (second) octant solution predicts the lightest neutrino mass, $m_3 \sim 29~\text{meV}$ ($m_3 \sim 65~\text{meV}$) and the $CP$ phase, $\delta_{CP} \sim -\frac{\pi}{4}$ ($\delta_{CP} \sim \frac{\pi}{2}$), offering the possibility of large observable $CP$ violating effects in future experiments.Comment: 9 pages, 3 figure

Strategic Management of Human Capital as Rural Praxis

The purpose of this mixed-methods study was to investigate teachers\u27 and administrators’ perceptions about the current state of human capital management in a rural Northern state. The study also sought to uncover ways in which rural districts could better leverage their unique advantages and minimize their place-based challenges by investing in a more strategic approach to human capital management (HCM). Human resource practices within the education industry have not kept pace with advances in the human resources profession (Tran, 2015). Strategic HCM is a crucial underutilized approach to helping districts deliver on their vision of equitable access (Odden et al., 2011; Tran, 2015; Tran et al., 2020). This study used a survey, one-on-one interviews, and focus groups to assess the degree to which human capital management programs are perceived as effective by district leaders and teachers in four rural Maine school districts – two in the north (Region 1) and two in the south (Region 2). To better understand educator perceptions of how HCM practices are being carried out, the study developed and administered a survey (overall Cronbach alpha = 0.974) and analyzed responses of teachers (N = 127) and administrators (N = 18) on eight constructs covering human resource planning, recruitment, selection, new teacher support, performance evaluation and professional growth, recognition and reward, community engagement, and school environment. When comparing responses of teachers and administrators, there were statistically significant differences between their perceptions of certain constructs. There were also significant differences in perceptions across northern and southern regions of the state. When analyzing survey data in conjunction with open-ended items and interviews, key themes emerged that included, for example, the importance of integrating and aligning HCM practices, strengthening alliances with higher education, formalizing hiring, streamlining evaluation, and using data and professional development more strategically. These and other study findings have implications for scholarly practitioner practice and future research and should help to inform improvements to local and state educational policy as it relates to strategic management of human capital in rural education

A Brief Overview of the Life and Work of Lyon Henry Appleby, M.D. (1895-1970).

The life and work of Dr. Lyon Henry Appleby, M.D., portrays the essence of a devoted clinician committed to scholarly excellence. Born in Deseronto, Ontario, in 1895 and passing in 1970, Dr. Appleby influenced all areas of general surgery, most notably popularizing a procedure that bears his name today. After a tour in World War I, he quickly proved himself to be a dedicated clinician with roots in academia, which translated into excellence within the Department of Surgery at St. Paul\u27s Hospital in Vancouver, Canada. He served in various leadership roles including Chair of the Department of Surgery, President of the International College of Surgeons, and Fellow of the Royal College of Physicians and Surgeons. The Appleby procedure, or en bloc removal of the celiac axis, at the time of gastrectomy, is the technical focus of this paper, although reference is made to Appleby\u27s extensive contributions to historical medicine

Energy Resources

With: Salter, C. L. The urban enigma