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Crop Yield Prediction at Multiple Spatial Scales with Statistical Machine Learning
No full textUnderstanding and accurately predicting crop yield is becoming increasingly important today in the face of global food security challenges, and thus, the availability of standardized data and scalable models is the need of the hour. To support this, researchers have developed CY-Bench (Crop Yield Benchmark), a comprehensive dataset that helps forecast maize and wheat yields on a global scale. This research project primarily involved working with the CY-Bench dataset aiming to improve crop yield prediction through machine learning. Initially, papers explaining the CY-Bench dataset and other papers for agriculture modeling were studied and analyzed in detail. The research then progressed to reproducing the benchmark results, showcasing the accessibility of the dataset. Building on this foundation, the research then progressed to developing new models such as regression trees and incorporating new derived features such as Leaf Area Index and Evapotranspiration in existing models. To streamline development, a subset focusing on Tippecanoe County was isolated from the broader US dataset. The results showed a reduction in MAPE for 2 out of the 3 models which were integrated with the newly engineered features. These initial outcomes are very promising, and there remains scope for further improvement. Including new features and experimenting with advanced models could potentially help improve the accuracy of the predictions
Methodology for Environmental Toxicology: Assessing Feeding and Rearing Strategies in Largemouth Bass (Micropterus nigricans) Larvae
Get PDFPoly- and perfluoroalkyl substances (PFAS) are an anthropogenic group of chemicals known for their persistence in the environment and their potential to bioaccumulate. PFAS can bioaccumulate in largemouth bass (Micropterus nigricans), yet the effects of exposure on bass larvae are unknown. While largemouth bass are commonly raised for aquaculture, techniques for rearing bass which enable controlled experiments at known densities, a necessity for toxicity studies, are poorly understood. Furthermore, the live prey typically used in existing approaches are not suitable for PFAS studies due to high background concentrations. The objective of this project was to assess different venues (indoors vs. outdoors) and feeding regimes to determine how to raise healthy larvae conducive to PFAS exposure studies.
Four treatment groups were used to determine the success of different combinations of venue and food: (1) indoor tanks with live zooplankton only, (2) indoor tanks with zooplankton and powdered Otohime A fish food, (3) outdoor tanks with a single zooplankton addition, and (4) outdoor tanks with zooplankton replenished daily. Live zooplankton samples were collected from the treatment groups and analyzed under a microscope to assess community composition, relative abundance, and to classify them by size. Larval survival, growth, and body condition were assessed with respect to observed densities of zooplankton across treatments.
Analysis did not detect statistical differences between indoor and outdoor rearing (p = 0.2398), food density (p = 0.2233), or an interaction of rearing and food density (p = 0.7392). However, density dependent growth with statistically significant relationships between outdoor treatment survival and length (p \u3c 2.2e-16), weight (p = 1.613e-9), and body condition factor (p = 0.04048) suggest food may have been a limiting factor. Increasing densities of edible zooplankton and conducting exposure studies outdoors appear to be the best approach for exposure studies with early-stage largemouth bass
Flowing Progress: Transforming the Danube Through Infrastructure
Get PDFFlowing Progress: Transforming the Danube Through Infrastructure focuses on how different political regimes and forms of governance have imagined and technologically transformed the most international river in the world. Multidisciplinary and drawing on methodologies of history, anthropology of infrastructure, and science, technology, and society, this collection explores the tensions between the river and its natural pulses, the humans that populate its floodplains, state agencies, and infrastructure. The book engages the concept of disturbance to point out the circular and spiraling dynamics between hydrological processes and technopolitical and economic practices. Disturbance denotes a specific type of long-term dynamic between human attempts to control the Danube, the material systems they implemented to achieve these goals, and the agency of the river that both enabled the functioning of infrastructure and the breakdown of such arrangements. It draws particular attention to the concerted efforts to contain and optimize the Danube’s flow, adding layer after layer of dams, channels, and pipes that could potentially escalate the power of a leashed river. Taking a longer historical perspective from the sixteenth century until today, the volume provides a variety of relevant case studies and local contexts in the Ottoman and Habsburg empires, and their successor states Austria, Hungary, Bulgaria, Romania, and Serbia which show different ways of how humans have imagined and coped with this mighty river.https://docs.lib.purdue.edu/ces/1011/thumbnail.jp
Ideal ranch riding horse
No full textThis video explains and describes the ideal ranch riding horse according to the American Paint Horse Association
Purdue University Preschool Language Program Curriculum
No full textThe Preschool Language Program is a play-based language-focused preschool in the Department of Speech, Language and Hearing Sciences at Purdue University. The program is co-led by a speech-language pathologist and early childhood educator. It supports children ages 3-5 with communication needs related to developmental language disorder, deaf/hard of hearing, autism, and other diagnoses. The curriculum focuses on language and whole child development throughout daily routines. This document includes an overview of the program, as well as an explanation of curriculum components with references. It also contains 24 weekly curriculum plans. The curriculum can be used by preschool teachers as a stand-alone classroom curriculum or by speech/language pathologists for language therapy
Anisotropic Residual Stress Measurements In Additively Manufactured 316 Stainless Steel Parts
No full textAdditive manufacturing (AM) using laser powder bed fusion (L-PBF) is increasingly used to produce complex parts for industries like aerospace and medical devices. The intrinsic characteristics of AM – layer-wise deposition and rapid thermal cycling – generate significant, anisotropic, residual stresses that can compromise part quality and performance. Recent studies highlight how these stresses are strongly influenced by process parameters and build orientation. X-ray diffraction (XRD) techniques, including sin²ψ and advanced two-dimensional approaches, have become the preferred methods for non-destructive, directionally resolved measurement of residual stress in AM metals. This review surveys advancements in XRD residual stress methods with a focus on the analysis of additively manufactured 316L stainless steel that has been post-treated by shot peening. Coordinated development of AM and shot peening underscores the importance of residual stress characterization to guide process optimization and improve the structural integrity of AM components across diverse industrial sectors
Converting a quarry dust to a potential SCM through calcination
No full textThe present work dealt with a by-product from quarry industry named as “blue clay” that was typically not reused in the past. Preliminary research found that this blue clay has muscovite, a common component of raw clays, indicating a great potential for it to be used as a SCM. In this study, we calcined the blue clay under different temperatures. Raw and calcined blue clay at four different temperatures were investigated on the following properties: amorphous silica content, specific surface area, heat flow and reactivity. Results show that calcination improves the amorphous silica content of the system thereby enhanced the chemical reactivity towards pozzolanic reaction. When used at a cement replacement rate of 20% by mass, the measured calcium hydroxide content decreased compared to the control sample, indicating the enhancement in the reactivity of the pozzolanic reaction
Activation of self-healing in pozzolanic natural hydraulic lime-based self-compacting concrete under cyclic compression
No full textThis study investigates the activation of autogenous self-healing in sustainable pozzolanic hydraulic lime self-compacting concrete under cyclic compressive loading. This cement-free formulation enhances crack closure and mechanical resilience, offering a promising alternative that improves durability and long-term performance for eco-friendly construction and restoration of heritage or low-carbon infrastructure
Performance of Carbonated Low-lime Calcium Silicate Composites Upon Exposure to Sea Water
No full textThis presentation compares the seawater resistance of carbonated mortar specimens made with a nonhydraulic calcium silicate cement and those made with Type I portland cement (OPC). Seawater resistance tests were conducted following procedures adapted from ASTM C1012, with all specimens exposed to artificial seawater prepared according to ASTM D1141-98 under three conditions: (a) room temperature (RT), (b) 60°C, and (c) deionized water (DI) as a reference. The study involved measuring length changes, visually assessing changes in specimen’s appearance, conducting microstructural characterization using scanning electron microscopy (SEM), performing thermogravimetric analysis (TGA), and analyzing the chemical composition of the soak solution using inductively coupled plasma optical emission spectroscopy (ICP-OES). The carbonated calcium silicate (CCS) mortar bars exposed to sea water solution at 60ºC showed only slightly greater expansion than those submerged at room temperature and their ultimate expansion remained below the critical limit (\u3c 0.1% at 18 months [1]). In contrast, the OPC mortar bars surpassed this threshold after approximately 3 months of exposure to sea water at room temperature. The SEM examination did not reveal any significant deterioration of the CCS specimens’ matrix after sea water exposure. However, it indicated noticeable de-calcification of the near surface region of the bars and ingress of magnesium species into the bulk paste. TGA results quantifying calcium carbonate phases aligned with SEM observations, while chemical analysis of the soak solutions further confirmed calcium leaching and magnesium infiltration into the CCS matrix
CO₂ Seeding Admixtures for Enhanced Concrete Activation
No full textIn this study, on-site CO2 seeding admixtures were prepared using power ultrasound-assisted pre-carbonation and chelator-assisted pre-carbonation (GLTA, EDTA) to enhance the carbonation efficiency and mechanical properties. Studies have shown that the application of power ultrasound can achieve a maximum CO2 uptake of 9.0% of the binder during the preacarbontion process. Compared with those of the traditional mixing batch and ordinary carbonation seeding activated batch, the strength of the power ultrasound seeding activated batch increased by 27.2 % and 21.4 %, respectively, after 1 day. Additionally, the EDTA-assisted pre-carbonation can achieve a maximum CO2 uptake of 9.6% of the binder during the preacarbontion process. Both early and later age strengths of cement mortar were enhanced by 21.33% at 1 day, 19.16% at 3 days, 16.00% at 7 days, and 16.38% at 28 days