VTechWorks Repository :: Browsing by Author "Lohani, Vinod K."

Browsing by Author "Lohani, Vinod K."

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Analysis of Roanoke Region Weather Patterns Under Global Teleconnections
LaRocque, Eric John (Virginia Tech, 2006-02-07)
This work attempts to relate global teleconnections, through physical phenomena such as the El Nino-Southern Oscillation (ENSO), Artic Oscillation (AO), North Atlantic Oscillation (NAO), and the Pacific North American (PNA) pattern to synoptic-scale weather patterns and precipitation in the Roanoke, Virginia region. The first chapter describes the behavior of the El Nino-Southern Oscillation (ENSO) by implementing non-homogeneous and homogeneous Markov Chain models on a monthly time series of the Troup Southern Oscillation Index (SOI), a sea level pressure based index. Meanwhile, in the second chapter the author has related or an attempt has been made to relate global teleconnections (through ENSO and AO) to a synoptic scale, station-centered set of weather types in order to assess trends in precipitation. The final portion of this work describes spatial variability of seasonal precipitation in southwestern Virginia in a context that incorporates global teleconnections (through AO, PNA, NAO, and ENSO) and frontogenesis. It was found that the Markov property can be used to describe and predict the monthly evolution of ENSO. Also evident is an increased probability of a wetter spring in the Roanoke region when El Nino combines with the negative phase of the AO during the previous winter. Meanwhile, Roanoke winters subsequent to a fall season described by this same El Nino-AO condition are predicted to receive more precipitation than average. This work additionally showed possible trends between frontal-precipitation events in the Roanoke region and global teleconnections.
The Assessment of Stream Discharge Models for an Environmental Monitoring Site on the Virginia Tech Campus
Rogers, Mark Richard (Virginia Tech, 2012-12-07)
In the Spring of 2012, hydraulic data was collected to calibrate three types of discharge models: stage-discharge, single-regression and multi-regression index velocity models. Unsteady flow conditions were observed at the site (â H/â t = 0.75 cm/min), but the data did not indicate hysteresis nor variable backwater effects on the stage-discharge relation. Furthermore, when corrected with a datum offset (α) value of -0.455, the stage-discharge relation r2 was equal to 0.98. While the multiple regression index velocity models also showed high correlation (r2 = 0.98) values, high noise levels of the parameter index velocity (Vi) complicated their use for the determination of discharge. Because of its reliability, low variance and accessibility to students, the stage-discharge model [Q = 5.459(H-0.455)^2.487] was selected as the model to determine discharge in real-time for LEWAS. Caution should be used, however, when applying the equation to stages above 1.0m. The selected discharge model was applied to ADCP stage (H) data collected during three runoff events in July 2012. Other LEWAS models showed similar discharge values (coefficient of variation = 0.14) while the on-site weir also produced similar discharge values. Precipitation estimates for July 19 and 24 rain events over the Webb Branch watershed were derived from IDW interpolated rain data and rainfall-runoff analyses from this data yielded an average ratio of 0.23, low for the urbanized watershed. However, since the three LEWAS models were very similar, and the on-site weir showed a lower value to LEWAS, it was concluded that any error in the ratio would be attributed to the precipitation estimate, and not the discharge models developed in this study.
Characterization of palmer drought index as a precursor for drought mitigation
Lohani, Vinod K. (Virginia Tech, 1995-08-15)
Coping with droughts involves two phases. In the first phase drought susceptibility of a region should be assessed for developing proper additional sources of supply which will be exploited during the course of a drought. The second phase focuses on the issuance of drought warnings and exercising mitigation measures during a drought . These kinds of information are extremely valuable to decision making authorities. In this dissertation three broad schemes i) time series modeling, ii) Markov chain analysis, and iii) dynamical systems approach are put forward for computing the drought parameters necessary for understanding the scope of the drought. These parameters include drought occurrence probabilities, duration of various drought severity classes which describe a region's drought susceptibility, and first times of arrival for non drought classes which signify times of relief for a drought-affected region. These schemes also predict drought based on given current conditions. In the time series analysis two classes of models; the fixed parameter and the time varying models are formulated. To overcome the bimodal behavior of the Pallner Drought Severity Index (PDSI), primarily due to the backtracking scheme to reset the temporary index values as the PDSI values, the models are fitted to the Z index in addition to the PDSI for the forecasting of the PDSI.
Characterizing Student Attention in Technology-Infused Classrooms Using Real-time Active Window Data
Mohammadi-Aragh, Mahnas Jean (Virginia Tech, 2013-06-06)
As computers become more prevalent (and required) in engineering classrooms, it becomes increasingly important to address the dichotomy in our current understanding of their impact on student attention and learning. While some researchers report increased student learning, others report computers as a distraction to learning. To address this conflict, the research community must gain a fundamental understanding of how students use their computers in-class and how student attention is connected to learning and pedagogical practice. By gaining such an understanding, instructors\' design of classroom interventions aimed at increasing positive computer usage will be better informed. The purpose of this quantitative research study is to answer the overarching question "How do students use computers in technology-infused classrooms?" through an investigation of student attention. Based on the premise that one\'s senses must be oriented towards a stimulus to receive the stimulus, it is hypothesized that attention in a technology-infused classroom can be measured by monitoring a students\' top-most, active window (the Active Window Method). This novel approach mitigates issues with prior data collection methods, and allows researchers the opportunity to capture real-time student computer usage. This research serves the dual purpose of validating the Active Window Method and investigating applications of the method. The Active Window Method is validated by comparing real-time active window data with in-class observations of attention in engineering courses with large enrollments. The bootstrap resampling technique is used to estimate mean error rate. Post-tests are used to establish convergent validity by relating learning to active window data. Polytomous logistic regression is used to examine the probability of post-test score (response) over the range of attention levels (factor). Subsequent to validation, two applications of the Active Window Method were pursued. First, student computer use is characterized in multiple large lecture sections. Second, in answering calls to link student computer usage to pedagogical practices, an investigation into the relationship between pedagogy and attention is conducted by aligning time stamps of the active window record with technology-infused pedagogical activities identified in video recordings of lectures. An intervention time series analysis is employed to quantify the change in average attention due to pedagogical activities. Results demonstrate strong construct validity when directly comparing active window and attention. Convergent validity was weak when relating active window to learning. Results from the two applications illustrate that instructors\' use of technology and their pedagogical practices impact student computer use. Specifically, collecting student-generated content and polling question activities encourage on-task behavior. However, activities that include a website link encourage off-task behavior.
Collaboratively Learning Computational Thinking
Chowdhury, Bushra Tawfiq (Virginia Tech, 2017-09-05)
Skill sets such as understanding and applying computational concepts are essential prerequisites for success in the 21st century. One can learn computational concepts by taking a traditional course offered in a school or by self-guided learning through an online platform. Collaborative learning has emerged as an approach that researchers have found to be generally applicable and effective for teaching computational concepts. Rather than learning individually, collaboration can help reduce the anxiety level of learners, improve understanding and create a positive atmosphere to learning Computational Thinking (CT). There is, however, limited research focusing on how natural collaborative interactions among learners manifest during learning of computational concepts. Structured as a manuscript style dissertation, this doctoral study investigates three different but related aspects of novice learners collaboratively learning CT. The first manuscript (qualitative study) provides an overall understanding of the contextual factors and characterizes collaborative aspects of learning in a CT face-to-face classroom at a large Southeastern University. The second manuscript (qualitative study) investigates the social interaction occurring between group members of the same classroom. And the third manuscript (quantitative study) focuses on the relationship between different social interactions initiated by users and learning of CT in an online learning platform Scratch™. In the two diverse settings, Chi's (2009) Differentiated Overt Learning Activities (DOLA) has been used as a lens to better understand the significance of social interactions in terms of being active, constructive and interactive. Together, the findings of this dissertation study contribute to the limited body of CT research by providing insight on novice learner's attitude towards learning CT, collaborative moments of learning CT, and the differences in relationship between social interactions and learning CT. The identification of collaborative attributes of CT is expected to help educators in designing learning activities that facilitate such interactions within group of learners and look out for traits of such activities to assess CT in both classroom and online settings.
A Comprehensive Decision Support System(CDSS) for Optimal Pipe Renewal using Trenchless Technologies
Khambhammettu, Prashanth (Virginia Tech, 2001-07-20)
Water distribution system pipes span thousands of miles and form a significant part of the total infrastructure of the country. Rehabilitation of this underground infrastructure is one of the biggest challenges currently facing the water industry. Water main deterioration is twofold: the main itself loses strength over time and breaks; also, there is degradation of water quality and hydraulic capacity due to build of material within a main. The increasing repair and damage costs and degrading services demand that a deteriorating water main be replaced at an optimal time instead of continuing to repair it. In addition, expanding business districts, indirect costs, and interruptions including protected areas, waterways and roadways require examination of trenchless technologies for pipe installation. In this thesis a new threshold break rate criterion for the optimal replacement of pipes is provided. As opposed to the traditional present worth cost (PWC) criterion, the derived method uses the equivalent uniform annualized cost (EUAC). It is shown the EUAC based threshold break rate subsumes the PWC based threshold break rate. In addition, practicing engineers need a user-friendly decision support system to aid in the optimal pipeline replacement process. They also need a task-by-task cost evaluation in a project. As a part of this thesis a comprehensive decision support system that includes both technology selection knowledge base and cost evaluation spreadsheet program within a graphical user interface framework is developed. Numerical examples illustrating the theoretical derivations are also included.
A comprehensive modeling approach for BMP impact assessment considering surface and ground water interaction
Cho, Jae-Pil (Virginia Tech, 2007-04-04)
The overall goal of this study was to develop a comprehensive tool for assessing the effectiveness of selected BMPs on both hydrology and water quality and to demonstrate the applicability of the system by considering 1) temporally and spatially changing land use management practice in an agricultural watershed and 2) interaction between surface and ground water over the entire system. A user interface and Dynamic Agricultural Non-point Source Assessment Tool (DANSAT) were developed to achieve this goal. DANSAT is the only distributed-parameter, physically-base, continuous-simulation, and multi-soil layer model for simulating impacts of agricultural BMPs on hydrology and water qulality in small agricultural watersheds. DANSAT was applied to QNB plot (18m Ã 27m) and two agricultural watersheds in Virginia, including Owl Run watershed (1140 ha) and QN2 in the Nomini Creek watershed (216 ha), to evaluate the model components and its performance in predicting runoff, sediment yield, and pesticide load. DANSAT performed well in predicting total runoff and temporal variations in surface runoff for both field-scale and watershed-scale applications. Total percent errors between the measured and predicted results were less than 10% except for one case (39.8% within a subwatershed of Owl Run watershed), while the daily Nash-Sutcliffe model efficiencies were greater than 0.5 in all applications. Predicted total sediment yields were within ±35% of observed values in all applications. However, the performance of DANSAT in predicting temporal trend and spatial distribution of sediment loads was acceptable only within Owl Run watershed, where high correlations between flow rates and sediment loads exist. The predicted total pesticide loads were within ±100% of observed values. DANSAT failed to simulate the temporal occurrence of pesticide loads with a 0.42 daily Nash-Sutcliffe efficiency value. The Dual-Simulation (DS) was developed within the linked ground water approach to resolve problems encountered due to the existence of different temporal scales between DANSAT and the existing ground water models such as MODFLOW and MT3D. The linked approach performed better in predicting the seasonal trend of total runoff compared to the integrated approach by showing an increase in monthly Nash-Sutcliffe efficiency value from 0.53 to 0.60. Surface and subsurface output variables were sensitive to the changes in spatially distributed soil parameters such as total porosity and field capacity. A maximum grid size of 100 m was recommended to be appropriate for representing spatial distribution of topographic, land use, and soil characteristics based on accuracy analysis during the GIS manipulation processes. Larger time-step based on predefined acceptable maximum grid size, decreased the computational time dramatically. Overall sensitivity to different grid sizes and time-steps was smallest for hydrology components followed by sediment and pesticide components. Dynamic crop rotation was considered by DANSAT, and the model successfully simulated the impacts of temporal and spatial changes in crop rotations on hydrology and water quality for both surface and subsurface areas. DANSAT could prove to be a useful tool for non-point source pollution managers to assess the relative effectiveness of temporally and spatially changing BMPs on both surface and ground water quantity and quality.
Decision Support Tool for Optimal Replacement of Plumbing Systems
Lee, Juneseok (Virginia Tech, 2004-12-10)
Pinhole corrosion leak in home plumbing has emerged as a significant issue. In the major water distribution system managed by municipalities and water utilities the costs are distributed among all subscribers. The home plumbing repair/replacement cost and possible water damage cost must be addressed by the home owner. There are also issues of the value of home, insurance rates, health consequences, and taste and odor problems. These issues have become major concerns to home owners. Cradle to grave life cycle assessment is becoming an integral part of industrial manufacturing. In this thesis comprehensive details pertaining to life cycle assessment are presented. Copper tubing for plumbing installations is mainly obtained from recycled copper. Various stages of copper plumbing pipe manufacturing are explained. A comprehensive synthesis of various corrosion mechanisms is presented. Particular reference is given to copper plumbing pipe corrosion. A decision support tool for replacing copper plumbing pipes is presented. The deterioration process is grouped into early, normal and late stages. Because available data reflects late stage process, an optimization, neural network and curve fitting models are developed to infer early and normal stage behavior of the plumbing system. Utilizing the inferred leak rates a non-homogeneous poisson process model is developed to generate leak arrival times. An economically sustainable replacement criterion is adopted to determine optimal replacement time.
Design and Implementation of a Real-Time Environmental Monitoring Lab with Applications in Sustanibility Education
Delgoshaei, Parhum (Virginia Tech, 2013-01-30)
In this dissertation, the design, implementation, and educational applications of a real-time water and weather monitoring system, developed to enhance water sustainability education and research, are discussed. This unique system, called LabVIEW Enabled Watershed Assessment System (LEWAS), is a real- world extension of various data acquisition modules that were successfully implemented using LabVIEW into a freshman engineering course (Engineering Exploration, ENGE 1024) at Virginia Tech. The outdoor site location measures water quality and quantity data including flow rate, pH, dissolved oxygen, conductivity, and temperature -- as indicators of stream health - for an on-campus impaired stream in real-time. In addition, weather parameters (temperature, barometric pressure, relative humidity and precipitation) are measured at the LEWAS outdoor site. The measured parameters can be accessed by remote users in a real-time through a web-based interface for education and research. LEWAS is solar powered and uses the campus wireless network through a high-gain antenna to transmit data to remote clients in real-time. Its power budget consisting of consumption (14 W), electrical storage, and generation (80 W, peak) is balanced to enable 24/7 operation regardless of weather conditions. An embedded computer with low power consumption and modules for communicating and storing data are installed in the field and it is programmed to process measured environmental parameters to be delivered to remote users. This computer is programmed both using a field programmable gate array (FPGA, for low power consumption and robust operation) and traditional microprocessor programming (for more flexibility). The environmental sensors of the system are routinely calibrated using established procedures. A LEWAS Development Platform was established to develop and test the system and to train and mentor several undergraduate and graduate students who helped in its implementation. A number of design and implementation challenges were overcome including extending campus Internet access to a location not included on the network and integrating hardware and software from three different sensor manufacturers into a unified software platform accessible over the Internet. To study the educational applications of LEWAS, an observational study was conducted as the system was gradually introduced to students in ENGE 1024 between 2009 and 2011. Positive student attitudes on the role of LEWAS to enhance their environmental awareness informed an experimental design implemented to study the motivational outcomes associated with the system. Accordingly, appropriate educational interventions and a hands-on activity on the importance of environmental monitoring were developed for both control and experiment groups, with only the latter given access to LEWAS to retrieve the environmental parameters for the activity. An instrument was developed on the theoretical foundation of the expectancy value theory of motivation and was administered to control and experimental groups in ENGE 1024. Altogether, 150 students participated in the study. Exploratory Factor Analysis (EFA) was applied which resulted in factors that group questions together based on interest, importance, real-time access, and cost (feasibility of monitoring). After conducting parametric and nonparametric statistical analyses, it was determined that there exists a statistically significant difference between control and experimental groups in interest, real-time, and cost factors. This finding implies that providing real-time access to environmental parameters can increase student interest and their perception of feasibility of environmental monitoring -- both major components of motivation to learn about the environment. Future extensions and applications of the system at Virginia Tech and beyond are discussed.
Development and Analysis of a Spiral Theory-based Cybersecurity Curriculum
Back, Godmar V.; Basu, Debarati; Naciri, William; Lohani, Vinod K.; Plassmann, Paul E.; Barnette, Dwight; Ribbens, Calvin J.; Gantt, Kira; McPherson, David (2017-01-09)
Enhance cybersecurity learning experiences of students at Virginia Tech’s large engineering program
Development and Evaluation of the Online Watershed Learning System (OWLS)
Brogan, Daniel S. (Virginia Tech, 2017-03-01)
Cyberlearning has the ability to connect learners from diverse settings to educational resources regardless of the learners' proximities to traditional classroom environments. Prior research has shown that hybrid learning systems more effectively improve student learning than do either traditional or cyberlearning approaches used individually. The Online Watershed Learning System (OWLS) is an interactive cyberlearning system for use in hybrid education. It serves as the end user interface of the Learning Enhanced Watershed Assessment System (LEWAS), a watershed monitoring system for use in research and education. The LEWAS/OWLS has been integrated into 26 courses. Within the theoretical framework of situated learning, the OWLS uses data and imagery to situate users at the LEWAS site. The current research has the dual goals of developing the OWLS and evaluating its effectiveness within a hybrid learning environment as part of watershed monitoring education. Within goal 1, HTML5, CSS and JavaScript code (11,112 lines) were used to achieve platform independence, and student and faculty feedback suggests a hierarchy of cyberlearning interface features, where anywhere/anytime access is the most important class of features for these users followed by real-time data visualization, system background information and how-to-use information in descending order. For students at the community college freshmen, university senior and graduate levels, goal 2 investigated how much the OWLS increases student learning of environmental monitoring topics and motivates them to study these topics. For this goal, use of the LEWAS/OWLS increased learning and motivation for most students with the caveats that the these gains were not always statistically significant and that these gains may be caused by use of the LEWAS in general rather than by the OWLS component of it. Additional studies are needed to resolve these issues. Additionally, a pilot test of anonymous user tracking (11,231 page views) showed how it can be used to obtain general information about which groups of users are accessing a cyberlearning system, how they are accessing it, and how navigation through the system can be improved to better match user goals. The full results and their limitations are included along with areas for future work.
From Landscapes to Waterscapes: A PSE for Landuse Change Analysis
Rubin, E.J.; Diet, R.; Chanat, J.; Speir, C.; Dymond, Randel L.; Lohani, Vinod K.; Kibler, David F.; Bosch, D. D.; Shaffer, Clifford A.; Ramakrishnan, Naren; Watson, Layne T. (Department of Computer Science, Virginia Polytechnic Institute & State University, 2000)
We describe the design and implementation of L2W — a problem solving environment (PSE) for landuse change analysis. L2W organizes and unifies the diverse collection of software typically associated with ecosystem models (hydrological, economic, and biological). It provides a web-based interface for potential watershed managers and other users to explore meaningful alternative land development and management scenarios and view their hydrological, ecological, and economic impacts. A prototype implementation for the Upper Roanoke River Watershed in Southwest Virginia, USA is described.
A GPS-IPW Based Methodology for Forecasting Heavy Rain Events
Gorugantula, Srikanth V. L. (Virginia Tech, 2003-05-15)
The mountainous western Virginia is the source of the headwater streams for the New, the Roanoke, and the James rivers. The region is prone to flash flooding, typically the result of localized precipitation. Fortunately, within the region, there is an efficient system of instruments for real-time data gathering with IFLOWS (Integrated Flood Observing and Warning System) gages, WSR-88D Doppler radar, and high precision GPS (Global Positioning System) receiver. The focus of this research is to combine the measurements from these various sensors in an algorithmic framework to determine the flash flood magnitude. It has been found that the trend in the GPS signals serves as a precursor for rain events with a lead-time of 30 minutes to 2 hours. The methodology proposed herein takes advantage of this lead-time as the trigger to initiate alert related calculations. It is shown here that the sum of the rates of change of total cloud water, water vapor contents and logarithmic profiles of partial pressure of dry air and temperature in an atmospheric column is equal to the rain rate. The total water content is measurable as the profiles of integrated precipitable water (IPW) from the GPS, the vertically integrated liquid (VIL) from the radar (representing different phases of the atmospheric water) and the pressure and temperature profiles are available. An example problem is presented illustrating the involving the calculations.
Hydrologic Evaluation of Low Impact Development Using a Continuous, Spatially-Distributed Model
Bosley II, Eugene Kern (Virginia Tech, 2008-07-11)
Low Impact Development (LID) is gaining popularity as a solution to erosion, flooding, and water quality problems that stormwater ponds partially address. LID analysis takes a spatially lumped approach, based on maintaining the predevelopment Curve Number and time of concentration, precluding consideration of the spatial distribution of impervious areas and Integrated Management Practices (IMP's), runoff-runon processes, and the effects of land grading. Success is thus dependent on the accuracy of the assumption of watershed uniformity, applied to both land cover distribution and flow path length. Considering the cost of long-term paired watershed monitoring, continuous, spatially-distributed hydrologic modeling was judged a better method to compare the response of LID, forest, and conventional development. Review of available models revealed EPA-SWMM 4.4H as the most applicable to the task. A 4.3-acre subwatershed of a local subdivision was adapted to LID using impervious surface disconnection, forest retention, and IMPs. SWMM was applied to the LID development at a fine spatial scale, yielding an 80-element SWMM model. The LID model was modified to reflect conventional development, with gutters, storm sewer, and detention. A predevelopment forest model was also developed. Two parameter sets were used, representing a range of assumptions characterized as favorable or unfavorable toward a particular development form. Modeled scenarios included favorable and unfavorable versions of Forest, LID, uncontrolled Conventional Development, and Conventional Development with Stormwater Management. SWMM was run in continuous mode using local rainfall data, and event mode using NRCS design storms. Runoff volumes, peak flows, and flow duration curves were compared.
Investigation of Personalized Learning and Engagement within a Cyberlearning System for Environmental Monitoring Education
Basu, Debarati (Virginia Tech, 2018-09-06)
Advance Personalized Learning is one of the 14 grand challenges of engineering as identified by the National Academy of Engineering. One possible approach for this advancement is to deploy systems that allow an investigator to understand the differences in the learning process of individuals. In this context, cyberlearning systems that use networked computing and communication technology to reach a large number of learners offer the affordance to uniquely identify learners and track their learning process in real-time. Motivated by this idea, this doctoral research aims to investigate personalized learning and engagement within a cyberlearning system, called the Online Watershed Learning System (OWLS). This cyberlearning system utilizes learning resources generated by a real-time high-frequency environmental monitoring system, called the Learning Enhanced Watershed Assessment System (LEWAS). The goals include advancing the OWLS with a user tracking system and data availability and visualization features and investigating personalized learning and engagement within the OWLS. A user-tracking system is developed utilizing a Node.js-based Express framework and deployed in the LEWAS server, which identifies individual users across devices such as laptops, tablets, and desktops, and detects their interaction within the OWLS, and stores the interaction data in a PostgreSQL database. HTML, CSS, and JavaScript technologies are used for the client-side development. Informed by the situative theory of learning and engagement theory, an investigation was carried out with 52 students from a junior-level civil engineering class. They completed an OWLS-based in-class task focused on concepts related to the environmental monitoring. Pre and post-surveys and the user-tracking system were utilized to collect data on individual student's perceived and conceptual learning, perceived and behavioral engagement, and perception towards the learning value of the OWLS. Results provide several insights into individual student's learning and engagement with the OWLS. For example, students gained knowledge using the OWLS, and their learning varied with the design of the in-class task, which, however, did not impact their engagement. Further, students' learning (scores on in-class task) had a significant negative relationship with their behavioral engagement (frequency of resource utilization of the OWLS). Additionally, temporal navigational strategies of 52 students were identified on an individual basis. Finally, variations in learning and engagement were analyzed in terms of factors such as gender and background knowledge. The study has implications for designing effective cyberlearning systems and learning activities that can utilize cyberlearning systems for leveraging technology-enhanced teaching and learning.
Investigations of Student and Team Creativity on an Introductory Engineering Design Project
Mullin, Jennifer Susan (Virginia Tech, 2010-02-04)
Engineering is widely accepted as a creative discipline. However, research focused on assessment of student creativity in engineering studies is lacking. Creativity by definition encompasses both novelty and value and has been approached through investigations of person, product, process and environment. Contemporary socio-cultural theories of creativity recognize the subjective nature of creativity in terms of a person, domain, and field. Domain specific viewpoints recognize the necessity of specialized skills and knowledge beyond the scope of general creativity to attain advanced levels of creative achievement within a given domain. Given the breadth of these theoretical perspectives, the overarching goal of this research was to initiate a foundational understanding of student creativity through a sustainable energy themed engineering design project developed specifically for an introductory engineering course at Virginia Tech. This embedded mixed-methods study approached creativity through assessment as well as significance of correlations between students' creative thinking abilities, their creative performance and their perceptions of the design experience in terms of known creativity factors on the 8-week long open-ended engineering design project. The study is comprised of two research themes; the investigation begins in theme one with a focus on individual creativity leading to investigation of team creativity in theme two with data collected over two successive semesters (i.e., spring â 07 and fall â 07). Creativity assessment measures included a test of creative thinking abilities, the Abbreviated Torrance Test for Adults (ATTA) as well as application of the Consensual Assessment Technique (CAT), a widely used creativity measurement technique, with graduate student judges assessing creativity of student's brainstorming ideas and final designs. Student surveys were administered for each theme to assess students' perceptions of the design project. Results reveal a significant correlation (p < 0.05) between students' ATTA scores and perceptions of the project as open-ended and interesting. Additional factors significantly correlated (p < 0.05) with students' perceptions of the design experience as creative included finding the project meaningful, interesting, exciting, enjoyable and surprising. Results of inter-rater reliability analysis followed by a two-way ANOVA illustrated difficulties in establishing consistency of judges' assessment of technical brainstorming ideas and final designs. Theme one findings with students repeatedly discussing the importance of their team in the creative process on the design project were further substantiated in theme two, bringing fresh insights concerning the role of collaboration in student creativity in the introductory engineering course. Implications for future research begin with the necessity for establishing reliable judging criteria and training as well as determining appropriate judges used in the assessment of students' creative performance on the design project. This research provides an essential starting point for researchers interested in developing engineering design curriculum to foster creativity.
Knowledge Creation Analytics for Online Engineering Learning
Teo, Hon Jie (Virginia Tech, 2014-07-25)
The ubiquitous use of computers and greater accessibility of the Internet have triggered widespread use of educational innovations such as online discussion forums, Wikis, Open Educational Resources, MOOCs, to name a few. These advances have led to the creation of a wide range of instructional videos, written documents and discussion archives by engineering learners seeking to expand their learning and advance their knowledge beyond the engineering classroom. However, it remains a challenging task to assess the quality of knowledge advancement on these learning platforms particularly due to the informal nature of engagement as a whole and the massive amount of learner-generated data. This research addresses this broad challenge through a research approach based on the examination of the state of knowledge advancement, analysis of relationships between variables indicative of knowledge creation and participation in knowledge creation, and identification of groups of learners. The study site is an online engineering community, All About Circuits, that serves 31,219 electrical and electronics engineering learners who contributed 503,908 messages in 65,209 topics. The knowledge creation metaphor provides the guiding theoretical framework for this research. This metaphor is based on a set of related theories that conceptualizes learning as a collaborative process of developing shared knowledge artifacts for the collective benefit of a community of learners. In a knowledge-creating community, the quality of learning and participation can be evaluated by examining the degree of collaboration and the advancement of knowledge artifacts over an extended period of time. Software routines were written in Python programming language to collect and process more than half a million messages, and to extract user-produced data from 87,263 web pages to examine the use of engineering terms, social networks and engineering artifacts. Descriptive analysis found that state of knowledge advancement varies across discussion topics and the level of engagement in knowledge creating activities varies across individuals. Non-parametric correlation analysis uncovered strong associations between topic length and knowledge creating activities, and between the total interactions experienced by individuals and individual engagement in knowledge creating activities. On the other hand, the variable of individual total membership period has week associations with individual engagement in knowledge creating activities. K-means clustering analysis identified the presence of eight clusters of individuals with varying lengths of participation and membership, and Kruskal-Wallis tests confirmed that significant differences between the clusters. Based on a comparative analysis of Kruskal-Wallis Score Means and the examination of descriptive statistics for each cluster, three groups of learners were identified: Disengaged (88% of all individuals), Transient (10%) and Engaged (2%). A comparison of Spearman Correlations between pairs of variables suggests that variable of individual active membership period exhibits stronger association with knowledge creation activities for the group of Disengaged, whereas the variable of individual total interactions exhibits stronger association with knowledge creation activities for the group of Engaged. Limitations of the study are discussed and recommendations for future work are made.
A Knowledge Map-Centric Feedback-Based Approach to Information Modeling and Academic Assessment
Castles, Ricky Thomas (Virginia Tech, 2010-01-28)
The structure of education has changed dramatically in the last few decades. Despite major changes in how students are learning, there has not been as dramatic of a shift in how student learning is assessed. Standard letter grades are still the paradigm for evaluating a student's mastery of course content and the grade point average is still one of the largest determining factors in judging a graduate's academic aptitude. This research presents a modern approach to modeling knowledge and evaluating students. Based upon the model of a closed-loop feedback controller it considers education as a system with an instructor determining the set of knowledge he or she wishes to impart to students, the instruction method as a transfer function, and evaluation methods serving as sensors to provide feedback determining the subset of the information students have learned. This method uses comprehensive concept maps to depict all of the concepts and relationships an educator intends to cover and student maps to depict the subset of knowledge that students have mastered. Concept inventories are used as an assessment tool to determine, at the conceptual level, what students have learned. Each question in the concept inventory is coupled with one or more components of a comprehensive concept map and based upon the answers students give to concept inventory questions those components may or may not appear in a student's knowledge map. The level of knowledge a student demonstrates of each concept and relationship is presented in his or her student map using a color scheme tied to the levels of learning in Bloom's taxonomy. Topological principles are used to establish metrics to quantify the distance between two students' knowledge maps and the distance between a student's knowledge map and the corresponding comprehensive concept map. A method is also developed for forming aggregate maps representative of the knowledge of a group of students. Aggregate maps can be formed for entire classes of students or based upon various demographics including race and gender. XML schemas have been used throughout this research to encapsulate the information in both comprehensive maps and student maps and to store correlations between concept inventory questions and corresponding comprehensive map components. Three software packages have been developed to store concept inventories into an XML Schema, to process student responses to concept inventory questions and generate student maps as a result, and to generate aggregate maps. The methods presented herein have been applied to two learning units that are part of two freshman engineering courses at Virginia Tech. Example student maps and aggregate maps are included for these course units.
Learning Analytics: Understanding First-Year Engineering Students through Connected Student-Centered Data
Brozina, Stephen Courtland (Virginia Tech, 2015-12-03)
This dissertation illuminates patterns across disparate university data sets to identify the insights that may be gained through the analysis of large amounts of disconnected student data on first-year engineering (FYE) students and to understand how FYE instructors use data to inform their teaching practices. Grounded by the Academic Plan Model, which highlights student characteristics as an important consideration in curriculum development, the study brings together seemingly distinct pieces of information related to students' learning, engagement with class resources, and motivation so that faculty may better understand the characteristics and activities of students enrolled in their classes. In the dissertation's first manuscript, I analyzed learning management system (LMS) timestamp log-files from 876 students enrolled in the FYE course during Fall 2013. Following a series of quantitative analyses, I discovered that students who use the LMS more frequently are more likely to have higher grades within the course. This finding suggests that LMS usage might be a way to understand how students interact with course materials outside of traditional class time. Additionally, I found differential relationships between LMS usage and course performance across different instructors as well as a relationship between timing of LMS use and students' course performance. For the second manuscript, I connected three distinct data sets: FYE student's LMS data, student record data, and FYE program survey data that captured students' motivation and identity as engineers at two time points. Structural equation modeling results indicate that SAT Math was the largest predictor of success in the FYE course, and that students' beginning of semester engineering expectancy was the only significant survey construct to predict final course grade. Finally, for the third manuscript I conducted interviews with eight FYE instructors on how they use student data to inform their teaching practices. Ten themes emerged which describe the limited explicit use of formal data, but many instructors use data on an informal basis to understand their students. Findings also point to specific, existing data that the university already collects that could be provided to instructors on an aggregate, class-level basis to help them better understand their students.
Long Term Hydrologic Effects on Stream Health from Residential Development Patterns
Lockard, Brendan Corbett (Virginia Tech, 2002-07-08)
In this study eight residential development scenarios are created for the mostly undeveloped Back Creek Watershed outside Roanoke, Virginia. The development scenarios include low, medium (cluster), medium (conventional), and high density development with and without development restrictions. These scenarios represent a large range of development as the land use imperviousness varies from 1% for the baseline condition to 34% for the most developed scenario. The hydrologic model HSPF is used to generate overland and channel flows from 43 years of rainfall. Hydrologic output from HSPF of the various landuse patterns from the eight scenarios are evaluated using Post Processor, a Visual Basic program. The results show that increased development causes a reduction in Back Creek's baseflow and an increase in the occurrence of both high and low flow extreme events. Overall, these results indicate that increased development will increase the variability of flowrate in Back Creek. Stream health impacts from flow variability were also analyzed with the Post Processor. First, hydrologic statistical variables with ecological relationships were used to gage the level of stream health impacts from flow variability. The averaged stream health index for the development scenarios was found to closely follow the amount of development, represented by the percent of impervious landuse. Second, the amount of velocity, depth, and both depth and velocity habitat available for three habitat guild representative species was evaluated for each scenario. The results indicated that increased development would lead to a substantial reduction in available riffle species habitat (represented by the fantail darter) and a moderate reduction in run and pool species habitat (represented by the central stoneroller and smallmouth bass, respectively). Overall, increased development has been found to have a negative impact on stream health. This impact should be considered in any future expansion of the Roanoke suburbs into this watershed.

Browsing by Author "Lohani, Vinod K."

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