(Visible) Tilings of Squares and Hypercubes

More than eighty years ago, Erdos considered sums of the side lengths of squares packed into a unit square.Here we consider various classes of tilings , this is, packings where there is no empty space inside the unit square. Several types of questions will be explored here. Various construction techniques are introduced, especially methods of generating tilings from tilings with fewer tiles. For some small values of n, I determine all tilings of the unit square with n tiles. I have found a best possible upper bound for a visible tiling, that is a tiling which every tile shares a face with the unit square. Furthermore, I generalize this result to higher dimensions for visible tilings

A New Approach to VFD System Specifications and Rebates

Variable frequency drives (VFDs) are used to provide flexibility and efficiency enhancements for agricultural pressurized irrigation systems. Standard 6-pulse VFDs commonly used for agricultural pumps can also create real problems with the pump motor and nearby electrical systems, unless mitigated by special equipment. With support by the California Polytechnic State University (Cal Poly) Irrigation Training and Research Center (ITRC), Pacific Gas and Electric Company (PG&E) recently began a new rebate program for installing VFD systems for pressurized irrigation. A major component of the new rebate program is the requirement to comply with a detailed set of minimum VFD system design and installation specifications. It was recognized that specifications were needed for farmers to receive comparable quotes for a good-quality VFD system, without needing to know all the technical details. Instead of a more typical qualified product list, which requires continuous time and effort to maintain, the specifications focus on minimum performance-based criteria and therefore provide flexibility for the VFD system designer. This paper provides an overview of the specifications’ content and rebate program implementation

Extra-Abdominal Desmoid Tumors Associated with Familial Adenomatous Polyposis

Extra-abdominal desmoid tumors are a significant cause of morbidity in patients with familial adenomatous polyposis syndrome. Understanding of the basic biology and natural history of these tumors has increased substantially over the past decade. Accordingly, medical and surgical management of desmoid tumors has also evolved. This paper analyzes recent evidence pertaining to the epidemiology, molecular biology, histopathology, screening, and treatment of extra-abdominal desmoid tumors associated with familial adenomatous polyposis syndrome

Western Diet in Adulthood, Timing of Menarche, and Economic Status Among Northeast Ohioans

I studied the age at first menstruation as a predictor of Western diet consumption among adults at The University of Akron and in Cleveland. I used stable carbon and nitrogen isotope compositions of human hair, as well as surveyed consumption of foods important to a Western diet (red meat, sugar, and dairy), to understand whether participants aligned with a Western dietary pattern. Age at survey and adult economic status were investigated as potential confounding variables. My data analysis and conclusions for this project has been completed and approved by my advisor and committee. To maintain collaborators\u27 ability to publish a comprehensive analysis of this dataset, I am not at liberty to publish my results here. Broader analyses of diet composition across lifetime, age at menarche, and economic status represent interesting avenues for future study

The convection connection: how ocean feedbacks affect tropical mean moisture and MJO propagation

The response of the Madden-Julian oscillation (MJO) to ocean feedbacks is studied with coupled and uncoupled simulations of four general circulation models (GCMs). Monthly mean SST from each coupled model is prescribed to its respective uncoupled simulation, to ensure identical SST mean state and low-frequency variability between simulation pairs. Consistent with previous studies, coupling improves each model's ability to propagation MJO convection beyond the Maritime Continent. Analysis of the MJO moist static energy budget reveals that improved MJO eastward propagation in all four coupled models arises from enhanced meridional advection of column water vapor (CWV). Despite the identical mean state SST in each coupled and uncoupled simulation pair, coupling increases mean-state CWV near the Equator, sharpening equatorial moisture gradients and enhancing meridional moisture advection and MJO propagation. CWV composites during MJO and non-MJO periods demonstrate that the MJO itself does not cause enhanced moisture gradients. Instead, analysis of low-level subgrid-scale moistening conditioned by rainfall rate (R) and SST anomaly reveals that coupling enhances low-level convective moistening for R > 5 mm/day; this enhancement is most prominent near the Equator. The low-level moistening process varies among the four models, which we interpret in terms of their ocean model configurations, cumulus parameterizations, and the sensitivity of convection to column relative humidity