VTechWorks
VTechWorks provides global access to Virginia Tech scholarship, including journal articles, books, theses, dissertations, conference papers, slide presentations, technical reports, working papers, administrative documents, videos, images, and more by faculty, students, and staff. Faculty can deposit items to VTechWorks from Elements, including journal articles covered by the University open access policy. Email vtechworks@vt.edu for help.
Open Access Policy
Virginia Tech's open access policy enables researchers to deposit the accepted version of scholarly articles with no embargo.
Theses and Dissertations
Virginia Tech was first in the world to require ETDs in 1997, and continues to add scans of older theses and dissertations.
Open Textbooks
More than 50 freely available and openly licensed textbooks are among our most downloaded items.
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Recent Submissions
Virginia Tech Carilion School of Medicine Course Catalog 2025-2026
(Virginia Tech Carilion School of Medicine, 2025)
The course catalog for the School of Medicine contains a complete listing of all classes, electives, clinical rotations, and independent study options and includes credit hours and any necessary prerequisites.
T-Type Labyrinth Seals Dynamic Response Evaluation Using Computational Analysis
Ashraf, Muhammad Mubashar; Untaroiu, Alexandrina (ASME International, 2026-03-06)
Effective sealing in rotating machinery is fundamental to maintaining efficiency and ensuring stable operation. Secondary leakage between high and low-pressure regions not only reduces performance but can also introduce destabilizing aerodynamic forces. Among annular gas seal technologies such as brush, hole-pattern, and honeycomb designs, labyrinth seals remain the most widely used because they are mechanically simple, reliable, and cost-effective. Recently, a modified T-type labyrinth seal has been introduced, demonstrating improved flow control and reduced flow-induced excitations compared to conventional straight-through configurations. The distinguishing feature of the T-type design is its T-shaped tooth geometry, which modifies the internal flow structure and enhances the inward radial forces associated with the Lomakin effect. This change in flow physics directly influences both leakage characteristics and rotordynamic behavior. Seal tip clearance plays a pivotal role. A smaller clearance generally reduces leakage but can alter aerodynamic stiffness and damping, thereby affecting rotor stability. Determining an appropriate clearance, therefore, requires more than a simple comparison at fixed geometry; it demands a structured parametric evaluation that captures the coupled aerodynamic and rotordynamic effects. Previous investigations have demonstrated leakage reductions of 23.6–25.3% for T-type labyrinth seals relative to straight-through designs, with axial length and tip clearance held constant. These findings point to clear performance advantages but leave open the question of optimal geometric tuning. Building on this, the present study conducts a sensitivity analysis using a design of experiments (DOE) framework coupled with steady-state computational fluid dynamics (CFD). The DOE approach enables systematic exploration of the clearance parameter space and quantifies the influence of the clearance parameter on leakage performance. In parallel, equivalent rotordynamic force coefficients are extracted from the CFD solutions to evaluate seal-induced stiffness and damping and to assess stability trends. To further establish practical relevance, the seal performance is examined across a range of pressure ratios and rotational speeds representative of aero-engine operating conditions. The results provide a coherent picture of how tip clearance governs both leakage and rotordynamic response in T-type labyrinth seals. Beyond confirming their leakage advantage, the study offers quantitative guidance for clearance selection and contributes to the broader effort to integrate aerodynamic performance and stability considerations into advanced seal design.
BMES 3984: Perspectives in Neurorehabilitation: Insights from Lived Experience,
Spring 2026
Gurari, Netta; Parcetich, Kevin; Sulzer, James; Pitterson, Nicole (2026-03)
This course offers students an immersive and interdisciplinary exploration of the lived experience of individuals navigating life after a brain injury. Through direct engagement with individuals with a brain injury, their carepartners, and healthcare professionals, students will gain insight into the complex medical, emotional, and societal challenges involved. Students will participate regularly in hands-on learning experiences, including community visits and clinical shadowing opportunities. Guest lectures and classroom interactions with healthcare providers will provide additional context on the neurorehabilitation process. By combining observational, experiential, and reflective learning methods, this course emphasizes the development of empathy, critical thinking, and an understanding of interdisciplinary collaboration in neurorehabilitation. Upon completion, students will have a deeper appreciation of the challenges and resilience associated with a brain injury, and be empowered to pursue careers that integrate technical skills with human-centered design and care.
Virginia Tech Shenandoah Valley Agricultural Research and Extension Center McCormick Farm 2024 Field Day Proceedings
(Virginia Tech, 2024-07-10)
The Shenandoah Valley AREC holds biennial field days to allow agricultural producers the opportunity to learn more about the research being conducted at the center and interact with those conducting the research.
Assessments with Double Simultaneous Tactile Stimulation following Stroke: A Scoping Review Protocol
Paul, Arco; Holstege, Noah; Johnson, Caroline; Shalaby, Mei; Yau, Jeffrey; Chui, Kevin; Parcetich, Kevin; Comer, C. Cozette; Gurari, Netta (2026-03-24)
Intact somatosensory perception is essential to interact with our surrounding environment, including when performing basic daily tasks and learning skilled movements. Successful execution of voluntary movements depends on accurately processing and perceiving the incoming somatosensory information through integrated sensorimotor pathways. Somatosensory impairments following stroke are relatively common, affecting upwards of 85% of survivors living with stroke. Loss of tactile perception is among the most frequent occurring of the somatosensory impairments, impacting approximately 50% of these individuals in the USA. Common tactile impairments include hypoesthesia (reduced ability to feel touch), dysesthesia (abnormal tactile perception), and impaired two-point discrimination (reduced ability to discriminate between two nearby locations of touch). These impairments are often assessed using unilateral tactile stimulation on the more severely-affected (paretic) side, and, accordingly, do not capture more complex tactile impairments that can arise during bilateral interactions. One such impairment is tactile extinction (TE), a condition in which individuals can detect unilateral tactile stimuli on either side of the body but fail to perceive the same tactile stimuli on the paretic side when both sides are stimulated simultaneously. Most activities of daily living rely on coordinating touching and feeling of objects and using both upper extremities to manipulate them in a dynamic manner, such that both arms are stimulated. Tactile dysfunction that suppresses perception during such bilateral tasks can disrupt motor performance in daily activities and recovery. Therefore, understanding the nature of tactile dysfunction during bilateral tasks following stroke is valuable when considering how to effectively assess and, in turn, treat individuals.
In this scoping review, we will explore approaches to assess tactile perceptual dysfunction during bilateral interactions post-stroke. Our aim is to summarize the current status of double simultaneous tactile stimulation approaches used for assessing tactile dysfunction. By considering the design of these approaches, we will identify need for further research, such as additional methods for assessment and implications of existing methods for interpreting why bilateral tactile dysfunction arises following stroke.