This work approaches the topic of modeling the atmospheric boundary layer in four research projects, which are summarized below. i) The diurnal cycles of near-surface meteorological parameters over Antarctic sea ice in six widely used atmospheric reanalyses were validated against observations from Ice Station Weddell. The station drifted from February through May 1992 and provided the most extensive set of meteorological observations ever collected in the Antarctic sea ice zone. For the radiative and turbulent surface fluxes, both the amplitude and shape of the diurnal cycles varied considerably among different reanalyses. Near-surface temperature, specific humidity, and wind speed in the reanalyses all featured small diurnal ranges, which, in most cases, fell within the uncertainties of the observed cycle. A skill score approach revealed the superiority of the ERA-Interim reanalysis in reproducing the observed diurnal cycles. An explanation for the shortcomings in the reanalyses is their failure to capture the diurnal cycle in cloud cover fraction, which leads to errors in other quantities as well. Apart from the diurnal cycles, NCEP-CFSR gave the best error statistics. ii) The accuracy of prediction of stable atmospheric boundary layers depends on the parameterization of the surface layer which is usually derived from the Monin-Obukhov similarity theory. In this study, several surface-layer models in the format of velocity and potential temperature Deacon numbers were compared to observations from CASES-99, Cardington, and Halley datasets. The comparisons were hindered by a large amount of scatter within and among datasets. Tests utilizing R2 demonstrated that the Quasi-Normal Scale Elimination (QNSE) theory exhibits the best overall performance. Further proof of this was provided by 1D simulations with the Weather Research and Forecasting (WRF) model. iii) The increasing number of physics parameterization schemes adopted in numerical weather forecasting models has resulted in a proliferation of inter-comparison studies in recent years. Many of these studies concentrated on determining which parameterization yields results closest to observations rather than analyzing the reasons underlying the differences. In this work, the performance of two 1.5-order boundary layer parameterizations was studied, the QNSE and Mellor-Yamada-Janjić (MYJ) schemes, in the Weather Research and Forecasting (WRF) model. The objectives were to isolate the effect of stability functions on the near-surface values and vertical profiles of virtual temperature, mixing ratio and wind speed. The results demonstrate that the QNSE stability functions yield better error statistics for 2-m virtual temperature but higher up the errors related to QNSE are slightly larger for virtual temperature and mixing ratio. A surprising finding is the sensitivity of the model results to the choice of the turbulent Prandtl number for neutral stratification (Prt0): in the Monin-Obukhov similarity function for heat, the choice of Prt0 is sometimes more important than the functional form of the similarity function itself. There is a stability-related dependence to this sensitivity: with increasing near-surface stability, the relative importance of the functional form increases. In near-neutral conditions, QNSE exhibits too strong vertical mixing attributed to the applied turbulent kinetic energy subroutine and the stability functions including the effect of Prt0. iv) In recent years, many eddy-diffusivity mass flux (EDMF) planetary boundary layer (PBL) parameterizations have been introduced. Yet, most validations are based on idealized setups and/or single column models. To address this gap, this study focused on the effect the mass flux part has on the performance in the QNSE-EDMF PBL scheme in the WRF model by comparing the results to observations from the CASES-97 field campaign. In addition, two refined versions, one introducing the parameterized clouds to the WRF radiation scheme, and the second adding a different entrainment formulation, were evaluated. The introduction of mass flux reduced errors in the average moisture profile but virtual temperature and wind speed profiles did not change as much. The turbulent flux profiles for modeled virtual potential temperature were little affected, with consistent reasonable agreement with observations, if one allows for biases in the observed data and modeled surface fluxes. However, the water vapor flux divergences from QNSE tend to be more negative than observed, while including the mass flux part tends to make the divergences more positive, the latter at least partially due to deeper model PBLs resulting from excessive model surface virtual temperature fluxes. Further, both virtual potential temperature and water vapor flux profiles display spurious spikes attributed to the way the non-local and local terms interact in the model. The influence of the mass flux schemes extends to 60 – 100-km scale circulation features, which were greatly modified by both the inclusion of mass flux and the new entrainment formulation. Adding mass flux based clouds to the radiation calculation improved the time and space averaged modeled incoming shortwave flux. The choice of the representation for entrainment/detrainment often affected the results to the same extent as adding mass flux did.

Thesis advisor: Gail C. Kineke / An observational study was conducted from 2013 to 2016 to investigate suspended-sediment transport processes in the stratified Connecticut River estuary. Time-series measurements of velocity and suspended-sediment concentration from the upper estuary were analyzed to determine the relative importance of different processes driving sediment flux under highly-variable river discharge. Results indicate that under high discharge the salt intrusion is forced towards the mouth causing large seaward sediment fluxes throughout the water column. Seaward fluxes are dominated by mean advection, with some contribution due to tidal pumping. Under low discharge the salt intrusion extends to the upper estuary, advancing as a bottom salinity front during each flood tide. Stratification and strong velocity shear during the ebb tide cause the upper and lower water column to become dynamically decoupled. Sediment flux near the bed is landward throughout the tidal cycle despite the net seaward depth-integrated flux, and is almost fully attributed to the mean estuarine circulation. River discharge is the primary factor affecting the magnitude and direction of sediment flux because of its high variability and direct connection to the salt-wedge dynamics. A generalized three-phase conceptual model describes suspended-sediment transport in shallow, stratified estuaries with low trapping efficiencies. First, fine sediment bypasses the estuary during high river flows and exports to the coastal ocean where a portion of this sediment is temporarily deposited outside the mouth. Second, during low discharge offshore mud deposits are reworked by wave- and tidally-driven currents and some sediment is advected back into the estuary with the advancing salt intrusion that transports sediment landward. Third, spatial salinity gradients facilitate sediment transport from the main channel to channel margins, marshes and off-river coves where it is retained and deposited long-term, as demonstrated in prior studies. This re-introduction and trapping of recycled sediment under low-discharge conditions can have important implications for pollutant transport, shoaling of navigation channels and harbors, and salt marsh accretion in the face of rising sea levels. / Thesis (MS) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Earth and Environmental Sciences.

Thesis advisor: Hans de Wit / Do employers prioritize the signal associated with the name of the university someone graduated from above an applicant’s skills in the employment process? Using a field experiment of the labor market, 2,400 fictitious applications were submitted to job openings in three countries: United States, United Kingdom, and Australia. The resumes belonged to fictitious citizens with full working rights, both female and male, that have attended universities of varying prestige in the United States, United Kingdom, and Australia respectively. Two skill-intensive sectors of the labor market were chosen: information and communication technology and accounting.  For each sector of the labor market, two resumes were designed. One resume had a high skills match with the generic requirements of entry level jobs in each sector. A second resume had a low skills match with the same requirements. For each country, one high-ranked university and one non-high-ranked university were selected to signal prestige. The name of the university the applicant graduated from and the sex of the applicant were randomly assigned on otherwise identical resumes. This study distinguished between the effects of human capital (Becker, 1975; Mincer, 1974; Schultz, 1959; 1961) and the signaling effect of university prestige in the labor market (Spence, 1973), while controlling for networking effects (Bayer, Ross, & Topa, 2005; Petersen, Saporta, & Seidel, 2000). The results suggest that human capital—as measured through the high and low skills match resumes—was statistically significant in predicting callbacks. Applications in the high skills match condition were 79% more likely to receive a callback than applications in the low skills match condition. The prestige condition and the interaction between university prestige and match were not statistically significant. This experiment detected no statistically significant differences in callback rates based on the sex of the applicant. These findings suggest that human capital, and not university prestige, predicts recruitment outcomes for applicants with a bachelor’s degree only. These results support a call for skill building and human capital consolidation at higher education institutions. / Thesis (PhD) — Boston College, 2019. / Submitted to: Boston College. Lynch School of Education. / Discipline: Educational Leadership and Higher Education.

Diplomová práce Proces vzniku hodnot: Mezigenerační přenos v rodině se zabývá procesem přenosu hodnotových orientací na individuální úrovni. Cílem práce je zjistit, zda a za jakých podmínek dochází k přenosu hodnot mezi generacemi v kontextu socio-profesní třídy. Práce se opírá o Kohnovu hypotézu, která tvrdí, že hodnoty jsou také kromě samotného procesu socializace formovány pracovní pozicí jednotlivců. Práce je rozdělena do dvou částí. Teoretická část pojednává o hodnotách, samotné socializaci jedince a shrnuje také poznatky Kohnovy práce, která se zabývá zejména diferenciací hodnot na základě profesních tříd. Analytická část se opírá o data z výzkumu "Distinkce a hodnoty 2008". Pozornost je zaměřena na zkoumání výchovných hodnot (které vlastnosti by měli být v dětech doma podporovány). Analytická část se také dělí na dva základní okruhy. První je věnován analýze hodnot potomků i rodičů skrze jednotlivé profesní třídy. Druhý okruh se věnuje přenosu jednotlivých hodnotových typů mezi generacemi. Klíčová slova Hodnoty, funkce hodnot, přenos hodnot, hodnotové orientace, socializace, socializační mediátoři, Kohnova hypotéza. Annotation The thesis The process of value formation: intergenerational transmission in family deals with the transmission of value orientations on the individual level. The aim...

A graph G is 2-stratified if its vertex set is partitioned into two nonempty classes (each of which is a stratum or a color class). We color the vertices in one color class red and the other color class blue. Let F be a 2-stratified graph with one fixed blue vertex v specified. We say that F is rooted at v. The F-domination number of a graph G is the minimum number of red vertices of G in a red-blue coloring of the vertices of G such that for every blue vertex v of G, there is a copy of F in G rooted at v. In this paper, we survey recent results on the F-domination number for various 2-stratified graphs F.

This project was originally conceived of as an exploration and written presentation of various dimensions of the contemporary social movement called the Women’s Liberation Movement. The exploration was to be through personal experience in the movement and research in movement literature. From a research point of view, the specific objective was to identify the issues and elements of the Women's Liberation experience for those who are involved, in other words, to determine what are the salient dimensions of this experience for the individual in Women’s Liberation.

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In 2018, the Orlando metro area was visited by 126.1 million tourists, a new record which the area has broken for its eighth year (Sanata 2019). As the number of visitors to the area continues to rise, so has the number of people employed by the hospitality industry which currently makes up the largest sector of the area's job market, employing 280,000 workers as of December 2019 (Bureau of Labor Statistics). Consistent growth in various insecure and unstable jobs of this kind have prompted the development of theory regarding the emergence of a new class known as the precariat. The precariat is largely defined by flexible labor which often leads to unstable employment and wage insecurity. Recently, business closures related to the COVID-19 pandemic have led to historic levels of unemployment nationwide, disproportionately affecting those employed in the hospitality industry and further exacerbating the instability and uncertainty that characterizes precarious work. The purpose of this study is to explore and evaluate the experiences of hospitality workers since business closures and to identify how race, gender, and income type may create stratification within the precariat. Data was collected from 254 participants using a 10-minute online survey based on the following dimensions: employment status, housing, healthcare, food security, access to and receipt of social services, and opinions regarding employer interactions and government relief. The results of this study identify the difficulties in maintaining household expenses and obtaining unemployment benefits during the pandemic as well as negative opinions regarding state and federal government response. Furthermore, analysis of race, gender, and income type within the precariat found significant differences between the overall wellbeing of women and men as well as among varying income types including salaried, tipped, and hourly workers.