Predicting Anthropogenic Underwater Pile Driving Noise Using Pile Driving Analyzer (PDA) DATA

In the past several years, there has been increasing concern about anthropogenic noise generated during marine pile driving. This concern is expected to increase concomitantly with increases in waterfront construction efforts associated with aging infrastructure and sea level rise. Several guidelines are available to help predict underwater noise transmission due to pile driving, but the issue with all these methods is that they require one to measure sound pressure levels at one locus or more from the driven pile. In the context of marine construction, adding specifications for underwater noise collection may be expensive or difficult because contractors typically have little experience making such measurements. A better solution would be to utilize data that are already regularly collected during pile driving noise to predict underwater sound levels. This thesis focused on investigating whether such a method could be developed using Pile Driving Analyzer (PDA) data since PDA data are always collected prior to production scale driving during roadway construction in the state of Florida. PDA data are often also collected throughout pile driving activities on all drives during roadway construction. Sound data were collected using a hydrophone-equipped buoy system at various sites across the state of Florida. Once sound data were collected, correlations were developed between the sound data and data from the PDAs. Results appeared to indicate that a correlation appears to exist between sound-level data and PDA results. This would appear to indicate that development of a noise-prediction method using PDA data may be possible in the future

Design and manufacturing proposal for a stair-climbing wheelchair without an external power source

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (leaf 26).With over two million wheelchair users in the United States, many buildings have struggled to provide accessible elevators and ramps for the disabled. The only other option for the disabled to ascend stairs is to purchase a high-tech battery-operated wheelchair with elaborate sensors and gyroscopes, which can cost around $25,000. As a result, there is a high demand for a cheap and efficient way to climb stairs with a practical wheelchair. With the safety of the user as a main concern, it is the goal of this report to provide a light-weight, inexpensive stair-climbing wheelchair. In order to significantly reduce cost of production, the wheelchair will not have any outside power source. The user's strength is the only means of energy for climbing. Our specific design relies on three critical modules: wheels with retractable spokes, a lock-in ratchet on the axel, and a seat-tilting mechanism. By focusing on integrating light-weight materials into the design, the force required to operate the wheelchair should be very manageable. The next stages of manufacturing were determined and explicitly outlined. Using SolidWorks and previously developed components, a complete manufacturing proposal has been formulated. The production calls for two additional wheels with retractable spokes, two locking mechanisms of the main axel, and a tilt-in-space feature using gas springs. The final product should provide the disabled with a safe, reliable, and inexpensive wheelchair capable of ascending nearly any staircase.by Alfredo Rivera [and] Timothy Studley.S.B

Teachers’ and School Directors’ Perspectives on Standardizing a Learning Management System for Blended Learning

The introduction of standardized learning management systems (LMSs) for blended learning (BL) in K–12 education in Puerto Rico signifies a pivotal shift towards enhancing educational environments with technology. This qualitative study was conducted to understand the perspectives of teachers and school directors on the LMS adoption process. Grounded in the concerns-based adoption model as its conceptual framework, the study aimed to elucidate the stages of concern and levels of use among educational stakeholders, shedding light on the multifaceted challenges and opportunities that technology integration brings to schools. Employing semistructured interviews with a selection of seven teachers and school directors, this research embarked on a detailed analysis of the conversations to discern patterns and themes. The data collected from these interviews underwent rigorous deductive and inductive coding processes to systematically identify and categorize the concerns, facilitating a nuanced understanding of the stakeholders\u27 perspectives. Key findings revealed a need for professional development, engagement of caregivers, and adequate financial support to address the identified concerns effectively. By focusing on the human aspects of integrating LMSs into teaching and learning practices, this study contributes to the broader discourse on educational technology for BL. This study also not only contributes to the academic discourse, but also serves as positive social change as a call to action for policymakers, educators, and leaders to forge a collaborative path toward a future where technology genuinely serves to enhance learning

Adaptación tecnológica de una máquina recuperadora de glp residual en tanques domésticos aplicación del modelo de dispersion

El presente trabajo tiene como fin el dimensionamiento de un sistema para la recuperación del GLP residual existente en los cilindros domésticos, con una capacidad de evacuación de 1.200 unidades diarias. Se inicia el trabajo a partir del análisis de información obtenida de sistemas utilizados en plantas de mantenimiento de cilindros para GLP, mediante la cual se definen los componentes del sistema. Posteriormente se genera un modelo del comportamiento del fluido al momento de evacuarlo del cilindro para estimar el tiempo que se requiere por unidad y la estimación de las capacidades de cada uno de los elementos constituyentes. Una vez obtenida esta información se procede a la selección de los equipos. Los objetivos deseados son: presentar una solución que reduzca las emisiones de GLP al medio ambiente, minimizando el riesgo potencial de existencia de áreas explosivas; mejorar las condiciones de trabajo de los operarios, evitando la inhalación de estos vapores; y, realizar un análisis económico que nos permita evaluar los costos y posibles beneficios que puede generar la ejecución de este proyecto

Safety and Mission Assurance Acronyms, Abbreviations, and Definitions

This NASA Technical Handbook compiles into a single volume safety, reliability, maintainability, and quality assurance and risk management terms defined and used in NASA safety and mission assurance directives and standards. The purpose of this handbook is to support effective communication within NASA and with its contractors. The definitions in this handbook are updated when the definition of the acronym or term is updated in the originating document

Aspectos motivacionales en el abandono y regreso a la actividad física

El objetivo del presente estudio es conocer las causas más frecuentes por las que los adolescentes abandonan la práctica de actividad física, así como, las causas y motivación de su regreso, sus consecuencias y emociones que le generó el abandono y el regreso a la actividad física. Se presenta un estudio no experimental, de tipo transversal. Atendiendo al tipo de variables utilizadas es de tipo cuantitativo y según el nivel de investigación es descriptivo-correlacional. Participaron 70 sujetos (35 mujeres y 35 hombres) con un rango de edad de 12 a 18 años, que asisten a realizar ejercicio físico en el CEDECO (Centro De Desarrollo Comunitario) y CARE (Centro de Alto Rendimiento) de Nuevo León. La mayoría de los participantes del estudio aludieron su abandono por que no le gustó la actividad física que realizaba y el principal motivo por el que se regresaron es porque les gusta realizar actividad física. Al abandonar la mayoría de los sujetos mencionaron que tuvieron problemas de integración a la sociedad y comenzaron a realizar actividades nocivas para la salud como beber y fumar. Al regresar a la actividad física la mayoría de los sujetos experimentaron un mejor estado de ánimo y autoestima. Las personas que abandonaron volvieron a realizar actividad física por la regulación de tipo identificada, la cual incrementó a medida que se tenía más años de abandono. ABSTRACT The main goal of this study is to determine the most common reasons why teens drop out of physical activity as well as the causes and motivation of his return, its consequences and emotions that led to the abandonment and the return to physical activity. A non-experimental and transversal study is presented. According to the type of variables used it is quantitative and the level of research is descriptive - correlational. The study included 70 subjects (35 women and 35 men) with an age range of 12-18 years; these people attend physical exercise in CEDECO and CARE de Nuevo León. Most study participants alluded its abandonment because they did not like physical activity performed and the main reason they came back is because they like physical activity. Leaving the physical activity, most of the subjects mentioned that they had problems integrating into society and began conducting activities harmful to health as drinking and smoking. Upon returning to physical activity, most subjects experienced a better mood and self-esteem. People who left the physical activity, returned to practice identified by regulation type, which increased as it had more years of neglec

Aplicación de una técnica no invasiva por autofluorescencia para la determinación de productos finales de glicación avanzada en Tabaquistas

Introducción: Los AGEs son el resultado de una reacción no enzimática entre carbohidratos y grupos aminos, creando productos irreversibles, asociados al envejecimiento y al daño tisular. Metodología: estudio experimental analítico, transversal, prospectivo. Se trabajó con estudiantes universitarios entre 18 y 30 años de edad tabaquistas y no tabaquistas; se realizaron 3 mediciones de fluorescencia en piel y orina con intervención dietética. Resultados: se estudiaron 33 sujetos, 16 fumadores y 17 no fumadores, 31 hombres y 2 mujeres. Con edad promedio de 22.2 años. No existió diferencia estadística significativa entre los dos grupos en cuanto a edad e IMC. (P=0.3 y P=0.1). Al comparar las mediciones en piel del día 0 y 7 en ambos grupos se observó diferencia estadística significativa, (P=0.02) (P= <0.0001) respectivamente; el día 3 no se observó diferencia estadística (P= 0.2). Las mediciones de fluorescencia en orina al compararse entre ambos grupos no se encuentra diferencia estadística significativa todas (P> 0.5). Al realizar una correlación de Pearson para el día 0 se obtiene una relación directa, positiva entre la cantidad de cigarrillos y los niveles de AGEs en piel. Discusión: En general los niveles de AGEs en piel son más elevados en sujetos tabaquistas (1.45 UA) vs no tabaquistas (1.75 UA). La concentración de AGEs en piel aumenta o disminuye dependiendo de la ingesta de los mismos ya sea por alimentos o tabaco; la medición de AGEs en orina permite diferenciar entre sujetos tabaquistas y no tabaquistas.Tesis presentada para optar al título de Doctorado en Medicin