Engineering faculty on writing: What they think and what they want

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Writing has been identified as an important skill for engineers, and while faculty generally agree that writing should be included in the engineering classroom, there are many barriers that may discourage faculty to do so. This survey explored how faculty are including writing in their classes, what barriers they face, and also asks faculty what resources they would like so that the inclusion of writing could be more realistic and feasible.

In terms of their approaches to incorporating writing in their courses, a majority of respondents reported sometimes or frequently assigning writing in the following types of assignments: project documentation, written explanations of homework, and short-answer questions on tests and quizzes. A majority of respondents also reported frequent use of grading rubrics for writing, as well as specifying the audiences for whom students should target their writing.

Respondents identified their top challenges to including writing in their courses, including large enrollments, lack of time, and lack of teaching assistants competent to assess writing. To address these challenges, the most favored suggestion was having teaching assistants trained to assess writing, followed by expanding the availability of writing resources for faculty and students. Additionally, the issue of student preparation was brought up on numerous occasions; faculty stated that previous negative experiences with student writing hindered faculty from including writing assignments in their courses.

In a perfect world, all faculty would have teaching assistants that were trained in teaching engineering writing. However, other more realistic resources include providing rubrics and sample work on an accessible and easy to use website. This paper reports on the faculty survey about writing and also how it relates the larger project that includes providing these important resources to faculty.

Writing to learn engineering: Identifying effective techniques for the integration of written communication into engineering classes and curricula (NSF RIGEE project)

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The inclusion of writing-based exercises in technical courses has multiple learning benefits to students. Writing exercises not only serve to improve students’ written communication skills (i.e., “learn to write”), but can also be leveraged to develop critical thinking skills and promote deeper understanding of technical concepts (i.e., “write to learn”). Nevertheless, while writing-intensive assignments are relatively common in upper-level technical courses, especially in the form of laboratory and project reports, writing is often absent in the larger, required core courses that are taken by large numbers of engineering students. This is a missed opportunity to both enhance student learning of technical content as well as missed chance for students to have more writing practice. This NSF RIGEE project aims to investigate, support, and promote the inclusion of writing in technical courses, particularly introductory and core courses. Analysis of an engineering instructor survey carried out as part of the project revealed concerns about assessment and feedback on students’ written work. Additionally, writing instructors were interested in the creation of guides designed to aid instructors in the creation and tailoring of writing prompts for use in their existing technical courses. This paper introduces preliminary resources we have created in response to these stated needs, in order to help instructors develop, implement, and assess writing assignments in their courses. Current resources include a decision tree to help instructors create writing assignments within their classrooms and assessment rubrics that can easily be adapted to specific writing assignment needs. Resources will continue to be developed during the remainder of the project, culminating in a writing website geared towards instructors.

Testing for synchrony in recruitment among four Lake Michigan fish species

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In the Great Lakes region, multiple fish species display intraspecific spatial synchrony in recruitment success, with interannual climate variation hypothesized as the most likely driver. In Lake Michigan, we evaluated whether climatic or other physical variables could also induce spatial synchrony across multiple species, including bloater (Coregonus hoyi), rainbow smelt (Osmerus mordax), yellow perch (Perca flavescens), and alewife (Alosa pseudoharengus). The residuals from stock–recruitment relationships revealed yellow perch recruitment to be correlated with recruitment of both rainbow smelt (r = 0.37) and alewife (r = 0.36). Across all four species, higher than expected recruitment occurred in 5 years between 1978 and 1987 and then switched to lower than expected recruitment in 5 years between 1996 and 2004. Generalized additive models revealed warmer spring and summer water temperatures and lower wind speeds corresponded to higher than expected recruitment for the nearshore-spawning species, and overall variance explained ranged from 14% (yellow perch) to 61% (alewife). For all species but rainbow smelt, higher recruitment also occurred in extremely high or low years of the North Atlantic Oscillation index. Future development of indices that describe the physical Great Lakes environment could improve understanding of how climate can synchronize fish populations within and across species.

Logarithmic velocity structure in the deep hypolimnetic waters of Lake Michigan

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The characteristics of the bottom boundary layer are reported from a Lake Michigan field study carried out in deep hypolimnetic waters (55 m depth) during the stratified period (June–September 2012). The sandy substrate at the measurement site was densely covered with invasive quagga mussels (mean size: 1.6 cm; mean density: 10,000 mussels m−2). The measurements reveal a sluggish, compact bottom boundary layer, with flow speeds at 1 mab less than 5 cm s−1 for most of the period, and a dominance of subinertial energy. A downwelling event caused the largest currents observed during the deployment (10 cm s−1 at 1 mab) and a logarithmic layer thickness of 15 m. In spite of the weak flow, logarithmic profile fitting carried out on high-resolution, near-bed velocity profiles show consistent logarithmic structure (90% of profiles). Flow was dominated by subinertial energy but strong modified by near-inertial waves. Fitted drag coefficients and roughness values are Cd1m = 0.004 and Z0 = 0.12 cm, respectively. These values increase with decreasing flow speed, but approach canonical values for 1 mab flow speeds exceeding 4 cm s−1. The estimated vertical extent of the logarithmic region was compact, with a mean value of 1.2 m and temporal variation that is reasonably described by Ekman scaling, 0.07 u*/f, and the estimated overall Ekman layer thickness was generally less than 10 m. Near-bed dissipation rates inferred from the law of the wall were 10−8−10−7 W kg−1 and turbulent diffusivities were 10−4−10−3 m2s−1.

Water quality estimation of river plumes in southern Lake Michigan using hyperion

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This study focuses on the calibration of an existing bio-geo-optical model for studying the spatial variability of water quality parameters including chlorophyll (CHL), non-algal particles (NAP), and colored dissolved organic matter (CDOM) in episodic river plumes. The geographic focus is the St. Joseph River plume in southern Lake Michigan. One set of EO-1 Hyperion imagery and one set of boat-based spectrometer measurements were successfully acquired to capture episodic plume events. Coincident water quality measurements were also collected during these plume events. In this study, a database of inherent optical properties (IOPs) measurements and spectral signatures was generated and used to calibrate the bio-geo-optical model. Field measured concentrations of NAP and CDOM at 67% of the sampled sites fall within one standard deviation of the retrieved means using the spectrometer measurements. The percentage of sites, 88%, is higher for the estimation of CHL concentrations. Despite the dynamic nature of the observed plume and the time lag during field sampling, 77% of the sampled sites show field measured CHL and NAP concentrations falling within one standard deviation of the Hyperion derived values. The spatial maps of water quality parameters generated from the Hyperion image provided a synoptic view of water quality conditions. Results show that concentrations of NAP, CHL, and CDOM were more than three times higher in conjunction with river outflow, and inside the river plumes, than in ambient water. It is concluded that the storm-initiated plume is a significant source of sediments, carbon and chlorophyll to Lake Michigan.

Shear dispersion from near‐inertial internal Poincaré waves in large lakes

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In this work, we study mixed layer lateral dispersion that is enhanced by near-inertial internal Poincaré waves in the offshore region of a large stratified lake, Lake Michigan. We examine the hypothesis that the vertical shear created by near-inertial internal Poincaré waves is not only an energy source for vertical mixing in the thermocline and mixed layer, but also enhances horizontal dispersion via an unsteady shear flow dispersion mechanism. Complex empirical orthogonal function analysis reveals that the dominant shear structure is observed to mirror the thermal structure, with the location of maximum shear gradually lowered as the mixed layer deepens. This changing structure of shear and vertical mixing produces different characteristics in shear flow dispersion between the early and later stratified periods. The estimated depth-averaged surface layer vertical turbulent diffusivity grows from 10-5 m2s-1 to 10-3 m2s-1 over the stratified period, and the associated lateral dispersion coefficients are estimated as 0.1 – 40 m2s-1. The Poincaré waves are found to enhance greatly lateral dispersion for times less than the inertial period following release. In contrast, sub-inertial shear is the dominant mechanism responsible for shear dispersion for times greater than the inertial period. A simple approximation of the dispersion coefficient for lateral dispersion is developed, which scales as the product of surface current velocity (or wind friction velocity) and mixed layer depth. The calculated dispersion coefficients agree well with Okubo’s diffusion diagram for times up to a week, which suggests that unsteady shear dispersion is a plausible mechanism to explain observed dispersion rates in the mixed layer for early times after release.

Something to write home(work) about: An analysis of writing exercises in fluid mechanics textbooks

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Something to Write Home(work) About: An Analysis of Writing Exercises in Fluid Mechanics TextbooksAs assessments of learning outcomes are increasingly emphasized through accreditationrequirements (e.g., via ABET) and other quality assurance initiatives, written communication isone area that engineering instructors often find challenging to incorporate and assess. This isparticularly true in large core courses at the sophomore and junior levels. In this project, ananalysis of writing-based problems in fluid mechanics textbooks attempts to locate theavailability of activities that would allow students to practice writing, to learn through writing,and to use writing to relate course content to broader applications and contexts.This study is part of a larger ongoing project to understand and expand the incorporation ofwriting in large-lecture engineering courses, including investigation of faculty perspectives andtextbook assignments and assessments. This snapshot of writing-across-engineering will theninform efforts to create a range of writing activities (and assessment methods), mapped to ABETlearning outcomes, that instructors can incorporate in large engineering classes. Our objective isto examine widely-used textbooks in thermodynamics, materials, circuits, statics, and dynamics.In the preliminary analysis reported in this paper, we study problem sets from five popular fluidmechanics textbooks to find problems requiring more than merely numerical or calculatedanswers. As these writing-based problems are identified, we will categorize them in terms of thetype of prompt they represent, such as asking for explanation of a solution, application of aconcept to real-world examples, or problem-solving that requires description of processes.Once the number and types of writing problems in these textbooks has been analyzed andorganized, we will further explore how well the texts support actually using these exercises inclass. While writing-based prompts might be present, for example, instructors might not havethe resources, expertise, and/or support needed to incorporate them in their classes. Morespecifically, examination of solution sets and instructor’s guides will reveal how much thetextbooks equip instructors to assign and then assess the writing prompts that do exist. Finally,the extant writing assignments will be mapped to ABET learning outcomes to see how promptscan potentially be used to address key learning outcomes, e.g., in relation to the studentoutcomes in ABET Criterion 3.The result of this analysis will be an understanding of how well popular fluid mechanicstextbook assignments guide students in writing, and how well the textbooks equip instructors tomake use of those assignments. We will use this data to identify areas in which more writingassignments and assessment training would be useful for the teaching of engineering. This paperwill likely be of particular interest to faculty and staff interested in using writing to support avariety of technical, professional, and global learning outcomes in core engineering courses.

Species‐specific effects of subdaily temperature fluctuations on consumption, growth and stress responses in two physiologically similar fish species.

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Fluctuations in water temperature can have important physiological consequences for fishes. Effects of daily thermal cycles are well studied and can be beneficial, increasing prey consumption and growth rates when mean and maximum temperatures of the fluctuations are at or below the species’ optimum temperature. While less studied, subdaily temperature fluctuations are also common in many aquatic habitats and can be caused by both natural and anthropogenic processes. We performed laboratory experiments to examine how two fish species (yellow perch, Perca flavescens, and walleye, Sander vitreus) with similar thermal preferences respond to chronic exposure to subdaily temperature variability. We selected temperature treatments that reflected observed thermal variation after examining water temperature data from multiple aquatic systems. We then separately exposed yellow perch and walleye to a stable 23 °C treatment and 12-h cycles of 23 ± 2 °C or 23 ± 4 °C for 45 days. Adult yellow perch exposed to fluctuations of 23 ± 4 °C over 12 h expressed higher consumption, growth and food conversion efficiency than fish experiencing stable 23 °C. Temperature fluctuations, though, resulted in mortalities and the development of skin ulcers in yellow perch that did not occur under stable temperatures. In contrast, the same 12-h temperature fluctuations did not result in mortalities or stress responses in juvenile walleye. Moreover, unlike yellow perch, growth rates of walleye were lower under 12-h temperature fluctuations compared with the stable 23 °C treatment. Our results indicate that species with similar thermal preferences can respond differently to the same subdaily temperature fluctuations.

Diets and growth potential of early stage larval yellow perch and alewife in a nearshore region of southeastern Lake Michigan

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Transition from endogenous to exogenous feeding is thought to be a critical period for many fish larvae, when prey availability (type, size, and density) and ambient physical conditions (e.g., temperature, water clarity) can strongly influence survival. In Lake Michigan, two important fish species, yellow perch (Perca flavescens) and alewife (Alosa pseudoharengus), hatch and, presumably, begin exogenously feeding in the nearshore zone, an area characterized by short-term variation in environmental conditions. During 2010-2011, we examined environmental conditions and spatial and temporal distributions of larval yellow perch, larval alewife, and their potential prey in a nearshore region of southeastern Lake Michigan. To consider implications of environmental conditions on larval fish habitat quality, we quantified diet contents of young larval yellow perch and alewife and modeled bioenergetic growth rate potential (an index of habitat quality) under observed and predicted prey consumption scenarios. As expected, in this dynamic nearshore zone temperatures, light levels, zooplankton prey availability, and resulting growth rate potential were highly variable. Many larval fish digestive tracts were empty, suggesting that starvation may affect cohort survival. Among early-feeding larval fish, relatively small diet items were common, with larval alewives consuming diatoms and larval yellow perch consuming veligers of invasive dreissenid mussels. Though the mechanisms underlying such prey consumption and the consequences of ingesting these prey items remain largely unexplored, our results suggest dreissenid mussel veligers present early-feeding larvae with a relatively abundant prey source that may partially offset the apparent low consumption of other prey sources within Lake Michigan’s nearshore region.

Thermal habitat quality of aquatic organisms near power plant discharges: potential exacerbating effects of climate warming

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Water temperature strongly affects aquatic ectotherms, as even slight temperature changes can have dramatic effects on physiological rates. Water bodies receiving industrial thermal discharges can undergo dramatic spatial and temporal changes in water temperature. To quantify effects on aquatic ectotherms, thermal habitat quality (bioenergetic growth rate potential; GRP) for zebra mussel, Dreissena polymorpha (Pallas), rusty crayfish, Orconectes rusticus (Girard), walleye, Sander vitreus (Mitchill) and smallmouth bass, Micropterus dolomieu (Lacepède) was estimated near two power plant thermal discharges on the Ohio River, USA, from 2010 to 2012 using bioenergetics models. These results were then compared with GRP under increased base temperatures representing climate warming. Growth rate potential for all species was low near the discharges during summer and highest in winter, with increasing prey consumption minimising the negative effects of increased temperatures. In their immediate vicinity, thermal discharges had a more adverse effect on GRP than plausible climate warming but primarily affected GRP over a small spatial area, particularly within 400 m downstream from the power plants. Examining thermal habitat suitability will become increasingly important as rising energy demand and climate change collectively affect aquatic organisms and their habitats.