Extraction and Quantification of Atrazine

Undergraduate Basi

Coupled Fluids-Radiation Analysis of a High-Mass Mars Vehicle

The NEQAIR line-by-line radiation code has been incorporated into the DPLR Navier-Stokes flow solver such that the NEQAIR subroutines are now callable functions of DPLR. The coupled DPLR-NEQAIR code was applied to compute the convective and radiative heating rates over high-mass Mars entry vehicles. Two vehicle geometries were considered - a 15 m diameter 70-degree sphere cone configuration and a slender, mid-L/D vehicle with a diameter of 5 m called an Ellipsled. The entry masses ranged from 100 to 165 metric tons. Solutions were generated for entry velocities ranging from 6.5 to 9.1 km/s. The coupled fluids-radiation solutions were performed at the peak heating location along trajectories generated by the Traj trajectory analysis code. The impact of fluids-radiation coupling is a function of the level of radiative heating and the freestream density and velocity. For the high-mass Mars vehicles examined in this study, coupling effects were greatest for entry velocities above 8.5 km/s where the surface radiative heating was reduced by up 17%. Generally speaking, the Ellipsled geometry experiences a lower peak radiative heating rate but a higher peak turbulent convective heating rate than the MSL-based vehicle

The Business of Choice: Why Students Select For-Profit Career Colleges in Northeast Florida and the Implications for Community College Leaders

Over the past decade, for-profit career colleges have faced significant scrutiny and increased governmental regulation. Even with the skepticism of critics, for-profit enrollments surged and had one of the fastest enrollment growths among higher education sectors. For-profit career colleges are typically known for their predatory marketing practices and exorbitant costs. However, there is a significant concern surrounding why students would attend an institution with such a high cost and a socially perceived low-probability of return on investment (Cellini, 2012; Iloh & Tierney, 2013). This study employs a case study methodology to examine the decision-making process of students who selected for-profit career colleges instead of community colleges in northeast Florida. The researcher utilizes Levin and Milgrom’s Rational Choice Theory which is based upon the premise that individuals have preferences and make decisions based upon those preferences (Levin & Milgrom, 2004). In this qualitative study, the researcher utilized document evidence, semi-structured interviews, and focus groups to examine how students arrived at their choice to attend a for-profit career college instead of a lesser expensive community college. The findings of the study provide a framework for higher education practitioners and leaders to utilize the information gathered to improve or modify their current admission and recruitment strategies to increase enrollment in community colleges among non-traditional students

The development of global awareness in elementary students through participation in an online cross-cultural project

This study provided insights about how to develop online cross-cultural projects designed to foster global awareness in upper elementary-age students. Three schools, located in the southern United States, Mexico and Turkey, implemented a cross-cultural model as part of a comparative case study. The primary goal of this research was to gain an understanding of how these populations develop global awareness in an online environment. A second goal was to determine the necessary implications for practice when conducting online, cross-cultural projects in upper elementary classrooms. During eight weeks of implementation, students participated in cross-cultural groups as members of an online community. Qualitative data were collected from the online threaded discussions, focus group interviews with eight case study participants, teacher interviews, parent interviews and observations. Quantitative data from the Inventory of Intercultural Sensitivity (ICCS) survey was collected. Results showed that online cross-cultural projects are an enjoyable and viable means of developing global awareness in upper elementary age students, and that the development of global awareness in an online environment is dependent upon changes in participants’ social comfort zones. Changes in social comfort zones were shown to best occur through social, collaborative experiences, with gender, learning styles and country of origin playing an important role in the design of the online cross-cultural projects. In addition, the study determined that while students enjoy learning about global issues from other students rather than from teachers and textbooks, active teacher involvement in cross-cultural project is necessary for student success. The project concluded that collaborative, constructivist instructional design is essential for the development of online cross-cultural projects

Scorpion: Close Air Support (CAS) aircraft

The objective is to outline the results of the preliminary design of the Scorpion, a proposed close air support aircraft. The results obtained include complete preliminary analysis of the aircraft in the areas of aerodynamics, structures, avionics and electronics, stability and control, weight and balance, propulsion systems, and costs. A conventional wing, twin jet, twin-tail aircraft was chosen to maximize the desirable characteristics. The Scorpion will feature low speed maneuverability, high survivability, low cost, and low maintenance. The life cycle cost per aircraft will be 17.5 million dollars. The maximum takeoff weight will be 52,760 pounds. Wing loading will be 90 psf. The thrust to weight will be 0.6 lbs/lb. This aircraft meets the specified mission requirements. Some modifications have been suggested to further optimize the design

Identifying features predictive of faculty integrating computation into physics courses

Computation is a central aspect of 21st century physics practice; it is used to model complicated systems, to simulate impossible experiments, and to analyze mountains of data. Physics departments and their faculty are increasingly recognizing the importance of teaching computation to their students. We recently completed a national survey of faculty in physics departments to understand the state of computational instruction and the factors that underlie that instruction. The data collected from the faculty responding to the survey included a variety of scales, binary questions, and numerical responses. We then used Random Forest, a supervised learning technique, to explore the factors that are most predictive of whether a faculty member decides to include computation in their physics courses. We find that experience using computation with students in their research, or lack thereof and various personal beliefs to be most predictive of a faculty member having experience teaching computation. Interestingly, we find demographic and departmental factors to be less useful factors in our model. The results of this study inform future efforts to promote greater integration of computation into the physics curriculum as well as comment on the current state of computational instruction across the United States

Speech coding at 4800 bps for mobile satellite communications

A speech compression project has recently been completed to develop a speech coding algorithm suitable for operation in a mobile satellite environment aimed at providing telephone quality natural speech at 4.8 kbps. The work has resulted in two alternative techniques which achieve reasonably good communications quality at 4.8 kbps while tolerating vehicle noise and rather severe channel impairments. The algorithms are embodied in a compact self-contained prototype consisting of two AT and T 32-bit floating-point DSP32 digital signal processors (DSP). A Motorola 68HC11 microcomputer chip serves as the board controller and interface handler. On a wirewrapped card, the prototype's circuit footprint amounts to only 200 sq cm, and consumes about 9 watts of power