Search for: All records

Oftentimes engineering design tasks are thought of as acultural and devoid of community inclusion and values. However, engineering design is inherently a cultural endeavor. Problems needing engineering solutions or design thinking are situated in a specific community and need community solutions. This work in progress paper describes initial efforts from a project to help elementary and middle school teachers create culturally relevant engineering design tasks for implementation in their classrooms. To integrate best practices for culturally relevant pedagogy, the engineering design framework developed by UTeach Engineering was adapted to specifically address community needs and cultural values. Changes to the framework also include culturally relevant instructional strategies for classroom implementation. To situate the engineering design steps within a culturally relevant framework questions involving communities and students’ cultural needs, values, and expectations were posed in each stage of the design process. A water filtration engineering design task was situated in the cultural concept of “Mni Wiconi” (Water is life in the Dakota language). This was taught in a summer professional development workshop for a cohort of elementary and middle school teachers, in rural North Dakota, with school districts comprised of large Native American student populations. Teachers adapted this design task for their individual classrooms and content areas (science, math, social studies, ELA) and implemented it in their classrooms in the fall of 2021. Additional support for teachers was provided with fall workshop days aimed at helping them with the facilitation of a culturally relevant engineering task. To integrate culturally relevant teaching and good engineering design tasks, the North Dakota Department of Public Instruction’s Native American Essential Understandings Teachings of our Elder’s website was used. This allowed teachers and students to have firsthand knowledge of how various science and engineering concepts are framed within the indigenous community. Professional development focused on how to situate culturally responsive teaching in engineering design. For example, in one of the school districts the water filtration task was related to increased pollution of a nearby lake which holds significant importance for the local Tribal Nation. In addition to being able to visibly witness the demand for cleaner water, the book “We are Water Protectors” written by Carole Lindstrom, was used to provide cultural grounding for the Identify and Describe stages of the engineering design framework. Case studies of how teachers incorporated the water filtration design task into their lesson plans are presented along with their suggestions on how to improve classroom implementation. Future work in the program includes teachers and their students developing engineering design tasks situated in their own communities and cultures. 

Technologies that are appropriate, affordable, and sustainable are needed to increase incomes and resilience among sub-Saharan African smallholder farmers. A combination of thermization and low-cost evaporative cooling, termed Evakuuling, was developed to enable rural smallholder dairy farmers to preserve their evening milk in the absence of grid-electricity. The “EvaKuula” was configured to be powered by biogas. Biogas is used for the thermization process of the system. The evaporative cooling component is powered by wind. Use of biogas from domestic biogas plants add circularity value to smallholder farms. However, domestic biogas plant set-ups are relatively high capital investments and as such, a financial barrier to co-adoption with the EvaKuula. To lower this barrier, other energy sources have been considered. The purpose of this study was to assess alternative energy sources to power the thermization component of the EvaKuula. The list of energy sources considered included biogas, butane, kerosene, charcoal, and firewood. These energy sources were assessed with respect to the sum of the social and market costs. The product of a unit of fuel cost and the units consumed represented the “market cost.” The product of the long-term social carbon cost and total carbon dioxide emission equivalence represented the “social cost.” Regular and improved stoves were included in the charcoal and firewood analysis. As expected, biogas ranked on top of the list, followed by butane and kerosene. However, butane and kerosene are not easily accessible in rural setting. Approximated 76% of farmers in rural sub-Saharan Africa rely on firewood to meet domestic needs like cooking. Butane and kerosene are the fuel sources predominantly used in urban and peri-urban areas, due to accessibility and affordability. Incomes are typically higher among urban dwellers. Therefore, with butane and kerosene not readily available to the target EvaKuula users, the next best option was firewood, provided it is combusted in improved efficient stoves such as Lorena type. Key words: alternative energy, evaporative cooling, sustainable development, food security, circularity, smallholder farmers 

The BigCode community, an open-scientific collaboration working on the responsible development of Large Language Models for Code (Code LLMs), introduces StarCoder and StarCoderBase: 15.5B parameter models with 8K context length, infilling capabilities and fast large-batch inference enabled by multi-query attention. StarCoderBase is trained on 1 trillion tokens sourced from The Stack, a large collection of permissively licensed GitHub repositories with inspection tools and an opt-out process. We fine-tuned StarCoderBase on 35B Python tokens, resulting in the creation of StarCoder. We perform the most comprehensive evaluation of Code LLMs to date and show that StarCoderBase outperforms every open Code LLM that supports multiple programming languages and matches or outperforms the OpenAI code-cushman-001 model. Furthermore, StarCoder outperforms every model that is fine-tuned on Python, can be prompted to achieve 40% pass@1 on HumanEval, and still retains its performance on other programming languages. We take several important steps towards a safe open-access model release, including an improved PII redaction pipeline and a novel attribution tracing tool, and make the StarCoder models publicly available under a more commercially viable version of the Open Responsible AI Model license. 

This qualitative study explores teachers’ perceptions of culturally relevant engineering design (CRED) through professional development (PD) that is the first phase of Project ExCEED (Exploring Culturally Relevant Engineering Education Design). The data were collected from nine participants from three public schools in North Dakota. The findings shed light on participants’ understandings of CRED, Next Generation Science Standards (NGSS), the engineering design cycle and determine how PD influences their views about CRED tasks. The findings suggest that the teachers perceive CRED tasks as authentic, sensitive to students’ needs, and modifiable to cross-curricular contents. The results of this study suggest that PD has a positive influence on participants’ culture-specific and engineering design knowledge, participants’ confidence with regards to implementing CRED and thinking beyond the classroom. 

The frequency of salt marsh dieback events has increased over the last 25 years with unknown consequences to the resilience of the ecosystem to accelerated sea level rise (SLR). Salt marsh ecosystems impacted by sudden vegetation dieback events were previously thought to recover naturally within a few months to years. In this study, we used a 13‐year collection of remotely sensed imagery to provide evidence that approximately 14% of total marsh area has not revegetated 10 years after a dieback event in Charleston, SC. Dieback onset coincided with a severe drought in 2012, as indicated by the Palmer drought stress index. A second dieback event occurred in 2016 after a historic flood influenced by Hurricane Joaquin in 2015. Unvegetated zones reached nearly 30% of the total marsh area in 2017. We used a light detection and ranging‐derived digital elevation model to determine that most affected areas were associated with lower elevation zones in the interior of the marsh. Further, restoration by grass planting was effective, with pilot‐scale restored plots having greater aboveground biomass than reference sites after two years of transplanting. A positive outcome indicated that the stressors that caused the dieback are no longer present. Despite that, many affected areas have not recovered naturally, even though they are located within the typical elevation range of healthy marshes. A mechanistic modeling approach was used to assess the effects of vegetation dieback on salt marsh resilience to SLR. Predictions indicate that a highly productive restored marsh (2000 g m⁻² year⁻¹) would persist at a moderate SLR rate of 60 cm in 100 years, whereas a nonrestored mudflat would lose all its elevation capital after 100 years. Thus, rapid restoration of marsh dieback is critical to avoid further degradation. Also, failure to incorporate the increasing frequency and intensity of extreme climatic events that trigger irreversible marsh diebacks underestimates salt marsh vulnerability to climate change. Finally, at an elevated SLR rate of 122 cm in 100 years, which is most likely an extreme climate change scenario, even highly productive ecosystems augmented by sediment placement would not keep pace with SLR. Thus, climate change mitigation actions are also urgently needed to preserve present‐day marsh ecosystems.

 

In efforts to increase the energy density of lithium-ion batteries, researchers have attempted to both increase the thickness of battery electrodes and increase the relative fractions of active material. One system that has both of these attributes are sintered thick electrodes comprised of only active material. Such electrodes have high areal capacities, however, detailed understanding is needed of their transport properties, both electronic and ionic, to better quantify their limitations to cycling at higher current densities. In this report, efforts to improve models of the electrochemical cycling of sintered electrodes are described, in particular incorporation of matrix electronic conductivity which is dependent on the extent of lithiation of the active material and accounting for initial gradients in lithiation of active material in the electrode that develop as a consequence of transport limitations during charging cycles. Adding in these additional considerations to a model of sintered electrode discharge resulted in improved matching of experimental cell measurements.