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A DATA-DRIVEN INTELLIGENT DECISION-MAKING MODEL FOR IRRIGATION SCHEDULING
Get PDFAgriculture dominates global water use. While irrigation improves crop production, it has become the largest consumption of freshwater. This means the already scare freshwater resources due to urban expansion and climate change are facing even more pressure. On the other hand, excessive irrigation in filed would also increase agriculture run-off, pollutes surface and ground water, depletes water sources, and soil nutrition, and salinizes soils. Therefore, optimizing irrigation management to sustain crop yield while eliminating water wastes in irrigation is vital to agriculture sustainability, environmental quality, and the national economy. In this research, a data-driven intelligent irrigation scheduling model is proposed to improve water use efficiency. This study contributes to the field of water management in agriculture by demonstrating the validity of HighResolution Land Data Assimilation System (HRLDAS) derived products in irrigation scheduling, and optimizing irrigation scheduling based on deep reinforcement learning. Soil moisture and evapotranspiration (ET) products simulated by HRLDAS are first evaluated and validated in Nebraska, the largest irrigation state in the U.S. ET and soil water balance and soil-moisture based irrigation methods are used to schedule the irrigation events base on the validated model output in order to demonstrate its usefulness in irrigation management. The water-saving effect of integrating forecasted rainfall in irrigation scheduling was also analyzed. Based on deep reinforcement learning, an irrigation scheduling model was built and validated in Nebraska, to optimizing the irrigation. Yield estimations from crop growth model (AquaCrop) and soil moisture/ET simulations from HRLDAS are integrated in this model. Results show a total 20-40% water-saving was achieved, and highest economic return can be obtained compared to other methods. As all utilized data (e.g., simulated soil moisture and ET) were published and visualized on WaterSmart Data Information Portal (DIP), the application of this model would cost no fee on data service or installation of any sensor
DAMAGE LIFE CYCLE ANALYSIS FOR PRESENT AND FUTURE CONDITION ASSESSMENTS USING STATISTICAL AND MACHINE LEARNING TECHNIQUES
Get PDFIn-service structures experience many changes and damages during construction and operation, affecting their serviceability and remaining life. Infrastructure assessment protocols require regular evaluation of a given structure for a variety of defects and aging phenomena. While there has been extensive research on improving data collection using Non-Destructive Evaluation (NDE) methods , the state of art is limited with regards to NDE data analysis with regards to damage quantification and multi-modal data integration. The purpose of this study is to provide an integrated framework for NDE data assessment including, damage detection and quantification, data correlation, and data fusion. Such analysis initially detects and quantify damages and then the damages are correlated to understand the relation between various measurement techniques. Finally, multi-modal data fusion combines the results of separate NDE methods to improve the assessment of condition ratings. This approach to NDE data analysis provides new and more reliable damage analysis capabilities and a more comprehensive understanding of a damaged structure’s condition, thereby improving decision-making for asset management. The individual aspects of this analytical framework were evaluated through a combination of laboratory and field experiments, yielding promising results
Incorporating Feminist Thought: Institutional Mechanisms and Epistemic Challenges in Sociology
Get PDFDespite the implementation of inclusive policies, and the associations and organizations that emerged in response to the women’s liberation and Civil Rights movements of the 1960s and 1970s in sociology (e.g., Women’s Caucus, SWS), preeminent feminist sociologists have asserted that the feminist revolution is far from complete (Stacey 2006), if not in danger of being reversed by a neoliberal agenda inside academia (Fraser 2013; Pereira 2017). This dissertation examines the historical intersections of feminist thought within the discipline of sociology throughout the 20th century and explores the mechanisms of inclusion and boundary-work that have shaped its institutionalization today. It examines the extent to which feminist perspectives have been adopted through various institutional mechanisms and the impact of these mechanisms on the production and circulation of feminist ideas in sociology. Additionally, the study investigates how leading feminist sociologists negotiate the epistemic status of feminist thought within the discipline. To better understand the nature of feminist thought within sociology, this dissertation takes a multi-dimensional approach, engaging with both epistemological and institutional practices. It reviews relevant literature, provides a historical context of sociology's development from economics, and explores the evolving relationship between these disciplines and their inclusion of women and feminist thought. Additionally, this research employs a mixed-methods approach, combining trend analysis of top sociology programs in the United States over the past 25 years and in-depth interviews with feminist sociologists. These interviews shed light on the nature of women, gender, and feminist (WGF) scholarship adopted within sociology, the boundary work conducted by feminist sociologists, and the negotiation of notions of "scientificity" in the social sciences
Social Memory of Violence and Enduring Colonialism: The Bioarchaeology of Resilience Among the Ancestral Puebloans
No full textRecent explorations of resilience theory and violence within bioarchaeology have provided new insight into the continual Indigenous struggle against colonialism by studying the recent and deep past. This study seeks to demonstrate how analysis of traumatic injuries in the skeletal record elucidates evidence of flexibility, rigidity, resilience, and persistence of cultural identities using mitigation techniques during periods of socioecological changes. By examining published analyses of skeletal samples from the Ancestral Southwest sites of Pueblo Bonito (800-1200 CE), Point of Pines (400- 1450 CE), Hawikku (1300-1680 CE), and San Cristobal (1300-1680 CE), this study explores risks and likelihoods for experiencing trauma in reaction to various socioecological relations and colonialism. Pueblo Bonito and Point of Pines represent two extremes, where Pueblo Bonito's use of violence as social control created a rigidity trap and Point of Pines provides evidence for successful mitigation techniques. Hawikku and San Cristobal exhibit higher likelihoods of experiencing traumatic injuries, relating to increased Spanish taxation and negative interactions with the Great Plains and Ute or Comanche communities. Uniquely, these colonial sites did not show an increase in lethal cranial trauma, providing evidence for resilience in the Ancestral Puebloan community via social memory of previously successful mitigation techniques and small-scale changes to the social adaptive system. The results demonstrate an increase in the experienced violence due to the biologically transformative event of colonialism while also suggesting evidence for cultural resilience and endurance that continues today amongst the descendent communities of the Ancestral Southwest
Exploring Language Assessment Literacy of English as a Foreign Language (EFL) University Instructors in Vietnam: A Mixed-Methods Study
Get PDFThe study aimed to elicit information from Vietnamese EFL university instructors about their knowledge and skills regarding the principles, theory, and practices of language assessment by means of revision and validation of the Language Assessment Literacy–Revised Vietnam (LAL-RV), which was previously developed by Kremmel and Harding (2020). A content validation study by expert review was performed and the LAL-RV was pilot tested. Drawing from a sample of 140 Vietnamese EFL university instructors, the study adopted a concurrent mixed-methods design in the form of a web-based survey. Psychometric properties of the LAL-RV were established by using exploratory factor analysis with principal axis extraction and oblique rotation.The analysis resulted in the removal of 32 of 71 initial items, leaving a two-component solution that explained 64.04% of the variance. Component one, knowledge of language assessment, was measured by 25 items, and component two, practical skills in language assessment, by another 14 items. High internal consistency was found for each subscale with Cronbach’s alpha ranging from .96 to .98, indicating that the final 39-item LAL-RV was valid and reliable to measure LAL for the particular group of Vietnamese EFL university instructors. The results indicated that LAL for Vietnamese EFL university instructors consisted of two major components—language assessment knowledge and practical skills in language assessment, and that they had a moderate level of LAL (M = 3.08/5.00, SD = .79), corresponding to the functional level within Pill and Harding’s (2013) proposed literacy continuum. At this level of LAL, Vietnamese EFL university instructors might not be professionally ready to perform assessment tasks effectively. Additionally, Vietnamese EFL university instructors’ perspectives were sought concerning areas where they needed to improve their language assessment knowledge and skills. Principles of language assessment and different types of assessment were identified as the most critical areas of language assessment knowledge. The most needed language assessment skills included writing test tasks and items, designing classroom-based assessments, evaluating language tests, and interpreting/analyzing standardized test scores. The study results could inform the Vietnam Ministry of Education and Training, curriculum developers, teacher educators, and university administrators about essential language assessment topics to include in English-language teacher education curricula as well as in professional development training agendas. Continuous professional development in language assessment based on Vietnamese EFL instructors’ feedback in the field will raise their levels of efficacy and support student achievement
Context-Dependent Mechanisms in Numerosity-Time Interactions
Get PDFHumans use magnitude information from the environment, like numerical quantity and time intervals, to make predictions and plan actions. Evidence shows magnitude dimensions interact and bias each other congruently: larger numerical quantities are perceived as lasting longer in duration than smaller quantities. However, because those studies required subjects to discriminate between stimuli, it is unclear if the congruency effect is due to decisional bias. To determine whether this phenomenon is dependent upon making comparisons, we investigated contextual changes in numerosity-time tasks across four experiments. First, a non-comparison bisection task was employed to reduce decisional bias. Subjects judged whether a dot quantity was small or large (seven log-spaced quantities 10–90) or whether a duration was short or long (seven log-spaced intervals 750–2250 ms). An incongruent effect was observed, with larger numerosities perceived as quicker in duration than smaller numerosities, contrary to previously reported findings. Other factors known to interfere with processing were tested: neither eye fixations nor memory affected judgments. Next, we verified the congruency effect using a discrimination task with the same stimuli, confirming the decisional bias hypothesis. To further test the hypothesis and eliminate decisional bias, subjects performed a time reproduction task using a continuous keypress paradigm. A version of the congruency effect emerged: durations were significantly over-reproduced and under-reproduced as numerosities increased and decreased, respectively. Overall, our findings indicate that contextual changes in task design induce response bias, modulating the effect direction
Ground-based light curve follow-up validation observations of TESS object of interest TOI 3877.01
Get PDFContext
Exoplanets have been a fairly recent topic of interest in the field of astronomy, only having been discovered for a few decades. However, despite the youth of their discovery, they’ve been a crucial part of astronomical studies; especially those orbiting their parent star in the “Goldilocks Zone”. These Earth-like planets could potentially serve as future homes for humanity, which is why they’re a huge topic of interest.
Aims
The goal of this investigation is to study data regarding the star Tess Object of Interest (TOI) 3877 to confirm suspicions that it is an exoplanet transiting in front of its star that is responsible for the dimming of its light levels.
Methods
The app AstroImageJ will be used to study and interpret the data of TOI_3877 by taking multiple images captured during the night of observation, sorting them based on shutter settings and exposure length, aligning them, and finally by cutting out outside noise to gather the light levels taken over the period of exposure and making a light curve graph
Nostalgia
No full textPanorámica histórica y filosófica de la experiencia nostálgica desde 1688 hasta nuestros días
THREE ESSAYS ON ANCESTRY AND POLITICAL ECONOMY
Get PDFRecent literature has recognized the importance of ancestry and deep roots foreconomic growth. One of the important channels by which these factors affect economic growth is through their effect on political institutions. Using U.S. ancestral county data presents the opportunity to study the effects of a diverse number of ancestries on a wide variety of political outcomes in a similar environment. This dissertation explores the ways in which these factors affect political outcomes and how these political outcomes affect economic growth. Chapter 1 summarizes literature on the topic and designs new deep roots measuresfor U.S. counties to measure their importance for economic growth. These measures include technological adoption rates, Kin Network Intensity Index, and adoption of settled agriculture. Chapter 2 takes these measures along with those developed by Fulford, Petkov,and Schiantarelli (2020) and considers their effect on election returns and local government spending. Looking at every election from 1900-2010, I run a fixed effects model to show that ancestral trust, technological adoption, state history, and home country GDP have a large effect on the voting patterns of U.S. counties. These results are robust to a host of controls for the factor of race and IVs. My study of local government financing covers the period from 1970 to 2010. These results indicate that our ancestral variables have a positive relationship with the level of local government spending but a negative relationship with government spending as a fraction of local GDP. High trust ancestries are more likely to spend a larger fraction of their budget on welfare assistance. Chapter 3 seeks to ascertain how these factors affect local economic growththrough the public sphere while holding these same factors constant within the private sphere. Are changes in ancestry within the lawmaker population important independent of ancestry change in the general population? To answer this, I designed a unique data set on the members of state legislators across the U.S. I then use surname data to estimate each legislator’s ancestry. This allows me to see the effect of changing ancestry within state legislatures on a county’s economic growth while controlling for county ancestry. My fixed effects results indicate that trust and state history within legislatures are independently important for local economic growth
Ground-based Light Curve Follow-up Validation Observations of TESS Object of Interest TOI 3792.01
Get PDFThe goal of this study was to further confirm, characterize, and classify TESS Object of Interest (TOI) 3792.01. This was done by analyzing the stellar light curve of this object. We remotely obtained ground based data from the Observatory at George Mason University. The data was visualized using the software AstroImageJ. Although the data was skewed due to a fluctuating thin cloud cover and an 8 hour uncertainty period when observed by TESS, we found that by using less obscured reference stars and the WIDTH_T1 Detrending Parameter, we were able to find data clear enough to work with. However, this data still retained a scatter percentage (RMS) of 1.8%. While comparing the estimated light curve to the data collected, we found that the RMS dropped suddenly to 1.28% during an 8 hour period. However, this is obviously still imperfect. Therefore, the results for this study are inconclusive but suggestive. Though no direct conclusion can be reached at this time, more data should be collected to compare to the current data in order to confirm TOI 3792.01 as a transit