Browsing by Subject "Validation"
Now showing 1 - 8 of 8
- Results Per Page
- Sort Options
Item Community college student success courses : an examination of faculty-student engagement and students' experiences with sense of belonging(2018-05-02) Haynes Robinson, Toniette Nicole; Cantú, Norma V., 1954-; Reddick, Richard J; Saenz, Victor B; Frederick, SharonCommunity colleges provide opportunities to those students who did not choose the traditional path of higher education. There is a high number of undergraduate minorities and first-generation college students in the greater population due to open access policies and flexible academic program options at community colleges (Juszkiewicz, 2015). With a diverse student body and academic backgrounds, some students may or may not need developmental education. Within some developmental education programs, these students may be required to take student success courses (SSC). This is just one of the many strategies to improve retention and persistence rates among first-time-in-college (FTIC) students. First year experience programs which include first year-seminars, SSC, advising, and other learning experiences, are linked to positive outcomes for first year students (Muraskin and Wilner, 2004; Upcraft, Gardner and Barefoot, 2005). There is a body of literature that indicates an association between participation in an SSC and a range of positive academic outcomes (Schnell & Doetkott, 2003; Boudreau & Kromney, 1994). In addition to student participating in SSC, Barnett (2011) conducted a study on community college students’ experiences with validation, which predicted the students’ sense of integration, and the students’ intent to persist. Students who experienced higher levels of faculty validation were more likely to feel a sense of integration and/or belonging in the college. Thus, faculty validation modestly predicted students' intent to persist. Although there is extensive research on nonacademic factors about engagement, such as student relationships and sense of belonging (Blackhurst et.al., 2003; Barnett, 2011; Strayhorn, 2012), less is known about the experiences of faculty-student engagement and how that relates to students’ sense of belonging inside an SSC in a community college setting. The purpose of this study is to examine faculty- student engagement within SSC and the students’ experience with sense of belonging. The researcher conducted a qualitative study framed by the Validation Theory (Rendon, 1994). The findings from this study recognizing that: (1) lecture and listening is the primary form of engagement inside the SSC course at Melba Rose College; support comes in the form of caring and validation and; (2) personal and academic connections allowed students to create and enhance sense of belonging to the institution and also allow for utilizing academic skills in other courses. Additional findings unveiled that college resources are essential and enhance the students’ college experience for students that are required to take skill building (developmental/remedial) courses.Item Designs and methodologies for post-silicon timing characterization(2013-05) Jang, Eun Jung; Abraham, Jacob A.Timing analysis is a key sign-off step in the design of today's chips, but technology scaling introduces many sources of variability and uncertainty that are difficult to model and predict. The result of these uncertainties is a degradation in our ability to predict the performance of fabricated chips, i.e., a lack of model-to-hardware matching. The prediction of circuit performance is the result of a complex hierarchy of models ranging from the basic MOSFET device model to full-chip models of important performance metrics including power, frequency of operation, etc. The assessment of the quality of such models is an important activity, but it is becoming harder and more complex with rising levels of variability and the increase in the number of systematic effects observed in modern CMOS processes. The purpose of this research is (i) to introduce special-purpose test structures that specifically focus on ensuring the accuracy of gate timing models, and (ii) to introduce methods that analyze the extracted information, in the form of path delay measurements, using the proposed test structures. The certification of digital design correctness (the so-called signoff) is based largely on the results of performing Static Timing Analysis (STA), which, in turn, is based entirely on the gate timing models. The proposed test structures compare favorably to alternative approaches; they are far easier to measure than direct delay measurement, and they are much more general than simple ring-oscillator structures. Furthermore, the structures are specified at a high level, allowing them to be synthesized using a standard ASIC place-and-route flow, thus capturing the local layout systematic effects which can sometimes be lost by simpler (e.g., ring oscillator) structures. For the silicon timing analysis, we propose methods that deduce segment delays from the path delay measurements. These estimated segment delays using our methods can be directly compared with the timing models. Therefore, it will be easy to identify the cause of timing mismatches. Deducing segment delays from path delays, however, is not an easy problem. The difficulties associated with deconvolving segment delays from measured path delays come from insufficient sampling points. To overcome this limitation, we first group the segments based on certain characteristics of segments, and adapt Moore-Penrose pseudo-inverse method to approximately solve the segment delays. Secondly, we used equality-constrained least squares methods, which enable us to find a unique and optimized solution of segment delays from underdetermined systems. We also propose another improved test structure that has a built-in test pattern generator, and hence does not require ATPG (Automatic Test Pattern Generation). It is a self-timed circuit, and this feature makes the test structure run as fast as it can. Therefore, measurements can be made under high speed switching conditions. Finally, we can study dynamic effects such as timing effects of different levels of switching activities and voltage drop with the new test structure.Item Learning and identity development through integrated engineering instruction in secondary science classrooms(2020-05-07) Chu, Lawrence, Ph. D.; Sampson, Victor, 1974-; Riegle-Crumb, Catherine; Crawford, Richard; Hutner, ToddOne of the purposes of this dissertation was to describe the development of an assessment – the ScEnario-Based Assessment of Design (SEAD) – that can be used to measure ability to design solutions to problems using disciplinary core ideas and science and engineering practices. Another was to understand how teacher use of an integrated engineering instructional model – Argument-Driven Engineering (ADE) – during 8th grade science courses affects students’ (a) ability as represented by scores on the SEAD and (b) understanding of science concepts. I also sought to examine how the performance of female students and underrepresented minority (URM) students compared to that of their counterparts in this context. A final purpose was to study the ways integrated instruction affects students’ engineering identity over time. The inclusion of engineering as a core science discipline in national standards is a result of affordances that engineering integration can have on learning outcomes. It is also a response to the call for broadened participation in the engineering workforce. ADE was developed in light of recommendations in the literature to support these outcomes. In this dissertation, I discuss the development of the SEAD and examine student learning and identity development through integrated engineering instruction. The SEAD was designed using an evidence-centered design approach and Rasch methods. I analyze testing and rating scale data using multiple regression and longitudinal multilevel modeling. Focus group data was also collected and analyzed. Students whose teachers enacted the ADE model with high adherence outperformed comparison students on nearly all performance expectations and on a test of science content knowledge. These students also increased more in their engineering recognition over time than comparison students. However, no interactions between enactment group and gender or underrepresented minority status were found on any outcomes. Results provide further evidence that engineering integration benefits relevant learning outcomes and aspects of engineering identity. But less is known about its impacts on improving outcomes for groups underrepresented in the field. This dissertation pushes researchers to examine how combining the use of instructional models with educating teachers on inclusive pedagogical practices can bring about more equitable learning experiences in science classrooms.Item Measuring the validity of self-monitoring heart rate and activity tracking wearables(2016-05) Dooley, Erin Elizabeth; Bartholomew, John B.; Jowers, EsbellePURPOSE: To examine the validity of wearable physical activity tracking devices. METHODS: Participants were 62 students. Participants wore a Polar HR chest strap, Actigraph GT3X+ Acceleremetor, Apple Watch, Fitbit Charge HR, Garmin Forerunner 225 and were connected to a metabolic cart. Participants completed a seated 10-min baseline period, 4-min stages of light, moderate and vigorous intensities, and a 10-min seated recovery. Heart rate (HR), energy expenditure (EE) and step count were examined for each bout of exercise. ANALYSIS: Two-way RM-ANOVA were performed to compare the ability of the wearable devices to accurately measure each outcome relative to the criterion. Paired-samples t-tests compared the number of steps in observed videos and those reported for Fitbit. RESULTS: For HR, Apple Watch was accurate at all stages except in light and moderate intensities, in which the device measured lower HR. The Fitbit Charge HR produced accurate results in moderate PA, but measured significantly higher HR readings at baseline and light activity and lower HR readings at vigorous intensity. The Garmin Forerunner 225 was only accurate at vigorous intensity PA and measured significantly higher HR readings at all other intensities. For EE, the Fitbit measured significantly higher EE for all stages except vigorous intensity and recovery stages. The Apple Watch and Garmin measured significantly higher EE at all PA intensities. The Fitbit measured significantly lower step count than the criterion at all PA intensities. DISCUSSION: This study provides novel findings for Apple Watch and Garmin devices and provides new information regarding Fitbit accuracy. No studies have reported accuracy of these devices to measure HR. Future studies should investigate why differences between the devices exist.Item Mocking embedded hardware for software validation(2016-08) Kim, Steve Seunghwan; Khurshid, Sarfraz; Bard, WilliamThis report makes the case for unit testing embedded systems software, a procedure traditionally found in application software development. While the challenges of developing and executing unit tests on embedded software are acknowledged, multiple solutions are presented. The GNU toolchain and a Texas Instruments microcontroller are used as an example embedded target. Two applications, one introductory and one more realistic, were developed for this embedded target using the C programming language. This report details the procedure required to apply open-source frameworks, Unity and CMock, to the two embedded applications. These frameworks, combined with the techniques outlined in this report, accomplished several goals of unit testing. The goals included automated validation of the embedded applications, increased code coverage, and protection against regression defects. In addition, it is shown how unit tests led to more modular software architecture. Potential ideas to extend this research to other tools, environments, and frameworks are also discussed.Item Quantifying grasp quality using an inverse reinforcement learning algorithm(2017-05) Horn, Matthew William; Landsberger, Sheldon; Pryor, Mitchell WayneThis thesis considers the problem of using a learning algorithm to recognize when a mechanical gripper and sensor combination has achieved a robust grasp. Robotic hands are continuously evolving with finer motor control and higher degrees of freedom which can complicate the ability of an operator to determine if a gripper has achieved a successful grasp. Robots working in hazardous environments especially need confirmation of a successful grasp as the cost of failure is often higher than in traditional factory environments. The object set found in a nuclear environment is the focus of this effort. Objects in this environment are typically expensive (or one-of-a-kind), rigid, radioactive (or toxic), dense, and susceptible to dents, scratches, and oxidation. To validate the robustness of a grasp option, an online inverse reinforcement learning approach is evaluated as a method to quantify grasp quality. This approach is applied to an industrial-grade under-actuated robotic hand equipped with 36 pressure sensors. An expert trains the inverse reinforcement learning algorithm to generate a reward function which scores each grasp so - when combined with fuzzy logic - provides a general success or fail along with a confidence level. Utilizing the trained inverse reinforcement learning algorithm in a glovebox environment reduces the number of potential failing and untrustworthy grasps by scoring executed grasps and rejecting grasps that are similar to prior failed grasps while allowing further execution of movement when a grasp has been scored highly. The trained algorithm incorrectly classified grasps of insufficient quality less than 5% of the time in experimental hardware tests, showing that the algorithm can be applied to the glovebox environment to improve grasp safety. Thus the combination of grasp selection and pressure sensor validation provides a more efficient, robust, and redundant method to assure items can be safely handled during remote automation processes.Item Toward a predictive model of tumor growth(2011-05) Hawkins-Daarud, Andrea Jeanine; Oden, J. Tinsley (John Tinsley), 1936-; Babuska, Ivo; Ghattas, Omar; Zaman, Muhammad H.; Cristini, Vittorio; Prudhomme, SergeIn this work, an attempt is made to lay out a framework in which models of tumor growth can be built, calibrated, validated, and differentiated in their level of goodness in such a manner that all the uncertainties associated with each step of the modeling process can be accounted for in the final model prediction. The study can be divided into four basic parts. The first involves the development of a general family of mathematical models of interacting species representing the various constituents of living tissue, which generalizes those previously available in the literature. In this theory, surface effects are introduced by incorporating in the Helmholtz free ` gradients of the volume fractions of the interacting species, thus providing a generalization of the Cahn-Hilliard theory of phase change in binary media and leading to fourth-order, coupled systems of nonlinear evolution equations. A subset of these governing equations is selected as the primary class of models of tumor growth considered in this work. The second component of this study focuses on the emerging and fundamentally important issue of predictive modeling, the study of model calibration, validation, and quantification of uncertainty in predictions of target outputs of models. The Bayesian framework suggested by Babuska, Nobile, and Tempone is employed to embed the calibration and validation processes within the framework of statistical inverse theory. Extensions of the theory are developed which are regarded as necessary for certain scenarios in these methods to models of tumor growth. The third part of the study focuses on the numerical approximation of the diffuse-interface models of tumor growth and on the numerical implementations of the statistical inverse methods at the core of the validation process. A class of mixed finite element models is developed for the considered mass-conservation models of tumor growth. A family of time marching schemes is developed and applied to representative problems of tumor evolution. Finally, in the fourth component of this investigation, a collection of synthetic examples, mostly in two-dimensions, is considered to provide a proof-of-concept of the theory and methods developed in this work.Item Validating the 1-cm orbit(2015-12) McWilliams, Hannah Elizabeth; Bettadpur, Srinivas Viswanath, 1963-; Ries, JohnDetermination of three dimensional orbit accuracy to the 1-cm level is a difficult problem for even today's most well-tracked satellites. Gravity fields that are extracted from low earth orbit (LEO) satellites operating near the 1-cm accuracy level provide a better understanding of Earth's systems. The importance of the 1-cm orbit requires a closer look at the means of orbit error validation for these LEO satellites. The focus of this analysis is on the orbits of the Gravity Recovery and Climate Experiment (GRACE) satellite pair. The main methods of validation used on GRACE are the analysis of SLR residuals and the generation of statistics of orbit overlaps. The derivation of a method based on the Guier plane analysis of range residuals is presented along with the results of its application. By combining the analysis of various methods for determining orbit accuracy, the processes for validating the 1-cm orbit are assessed. The results of the three methodologies applied to the SLR residuals for a dynamic orbit indicate that GRACE has radial orbit error of 1.5-cm root-mean-square (RMS) and a three dimensional orbit error of roughly 3-cm RMS. Therefore, it is highly unlikely that GRACE has achieved a 1-cm benchmark. The orbit overlaps study resulted in overly optimistic statistics and cannot be used as a measure of orbit accuracy.