Now showing items 3430-3449 of 3620

    • Unearthing Stealthy Program Attacks Buried in Extremely Long Execution Paths 

      Shu, Xiaokui; Yao, Danfeng (Daphne); Ramakrishnan, Naren (ACM, 2015-10)
      Modern stealthy exploits can achieve attack goals without introducing illegal control flows, e.g., tampering with noncontrol data and waiting for the modified data to propagate and alter the control flow legally. Existing ...
    • Unification of Problem Solving Environment Implementation Layers with XML 

      Shu, Jiang; Watson, Layne T.; Ramakrishnan, Naren; Kamke, Frederick A.; North, Chris (Department of Computer Science, Virginia Polytechnic Institute & State University, 2005), TR-05-02
      This paper describes how XML is used to unify the implementation layers of a problem solving environment WBCSim. WBCSim is a Web based simulation system designed to increase the productivity of wood scientists conducting ...
    • Uniform component of index structure induced in Ge-SiO2 fibers by spatially modulated ultraviolet light 

      Tsai, T. E.; Williams, G. M.; Friebele, E. J. (AIP Publishing, 1998-06-01)
      Experimental data are presented to show that Ge(1) and Ge(2) centers are induced by trapping photoinduced electrons from the conduction band, in agreement with our previous proposal that both are trapped electron centers. ...
    • Unit Tangent Vector Computation for Homotopy Curve Tracking on aHypercube 

      Chakraborty, Amal; Allison, Donald C. S.; Ribbens, Calvin J.; Watson, Layne T. (Department of Computer Science, Virginia Polytechnic Institute & State University, 1989), TR-89-39
      Probability-one homotopy methods are a class of methods for solving nonlinear systems of equations that are globally convergent from an arbitrary starting point. The essence of all such algorithms is the construction of ...
    • UNITY Algorithms for Detecting Stable and Non-Stable Termination Conditions in Time Warp Parallel Simulations 

      Richardson, Debra S.; Abrams, Marc (Department of Computer Science, Virginia Polytechnic Institute & State University, 1990), TR-90-62
      This paper extends work done by Abrams and Richardson on the topic of implementing global termination conditions and collecting output measures in parallel simulation. Concentrating on the Time Warp method for parallel ...
    • Universal system structure for low power adapters 

      Virginia Tech Intellectual Properties, Inc.; Li, Qiang; Lee, Fred C.; Huang, Xiucheng (United States Patent and Trademark Office, 2017-12-19)
      A two-stage power converter architecture including an isolation transformer and rectification of the isolation transformer output by an LLC resonant circuit and methodology for operating the same feeds an output voltage ...
    • A UNIX Micro Requirement for Computer Science Majors 

      Fox, Edward A.; Birch, Sandra E. (Department of Computer Science, Virginia Polytechnic Institute & State University, 1986), TR-86-11
      In the fall of 1985, over 230 freshmen majoring in computer science at Virginia Tech purchased microcomputers running the UNIX operating system, because of a vote in spring 1983 by the faculty of the Department of Computer ...
    • Unsteady nanoscale thermal transport across a solid-fluid interface 

      Balasubramanian, Ganesh; Banerjee, Soumik; Puri, Ishwar K. (American Institute of Physics, 2008-09-15)
      We simulate unsteady nanoscale thermal transport at a solid-fluid interface by placing cooler liquid-vapor Ar mixtures adjacent to warmer Fe walls. The equilibration of the system towards a uniform overall temperature is ...
    • Unsupervised Deconvolution of Dynamic Imaging Reveals Intratumor Vascular Heterogeneity and Repopulation Dynamics 

      Chen, Li; Choyke, Peter L.; Wang, Niya; Clarke, Robert; Bhujwalla, Zaver M.; Hillman, Elizabeth M. C.; Wang, Ge; Wang, Yue (PLOS, 2014-11-07)
      With the existence of biologically distinctive malignant cells originated within the same tumor, intratumor functional heterogeneity is present in many cancers and is often manifested by the intermingled vascular compartments ...
    • Unsupervised Spatial Event Detection in Targeted Domains with Applications to Civil Unrest Modeling 

      Zhao, L; Chen, F; Dai, J; Hua, T; Lu, C-T; Ramakrishnan, N (PLOS, 2014-10-28)
    • Update on Multirate Timestepping Methods for Hyperbolic Conservation Laws 

      Constantinescu, Emil M.; Sandu, Adrian (Department of Computer Science, Virginia Polytechnic Institute & State University, 2007-03-01), TR-07-12
      This paper constructs multirate time discretizations for hyperbolic conservation laws that allow different timesteps to be used in different parts of the spatial domain. The proposed family of discretizations is second ...
    • Upper limit for the modulation bandwidth of a quantum dot laser 

      Asryan, Levon V.; Suris, R. A. (AIP Publishing, 2010-05-01)
      We derive a closed-form expression for the upper limit for the modulation bandwidth of a semiconductor quantum dot (QD) laser. The highest possible bandwidth increases directly with overlap integral of the electron and ...
    • UPS-indel: a Universal Positioning System for Indels 

      Hasan, Mohammad Shabbir; Wu, Xiaowei; Watson, Layne T.; Li, Zhiyi; Zhang, Liqing (Nature, 2017-10-26)
      Storing biologically equivalent indels as distinct entries in databases causes data redundancy, and misleads downstream analysis. It is thus desirable to have a unified system for identifying and representing equivalent ...
    • Urban pollution greatly enhances formation of natural aerosols over the Amazon rainforest 

      Shrivastava, Manish; Andreae, Meinrat O.; Artaxo, Paulo; Barbosa, Henrique M. J.; Berg, Larry K.; Brito, Joel; Ching, Joseph; Easter, Richard C.; Fan, Jiwen; Fast, Jerome D.; Feng, Zhe; Fuentes, Jose D.; Glasius, Marianne; Goldstein, Allen H.; Alves, Eliane Gomes; Gomes, Helber; Gu, Dasa; Guenther, Alex; Jathar, Shantanu H.; Kim, Saewung; Liu, Ying; Lou, Sijia; Martin, Scot T.; McNeill, V. Faye; Medeiros, Adan; de Sa, Suzane S.; Shilling, John E.; Springston, Stephen R.; Souza, R. A. F.; Thornton, Joel A.; Isaacman-VanWertz, Gabriel; Yee, Lindsay D.; Ynoue, Rita; Zaveri, Rahul A.; Zelenyuk, Alla; Zhao, Chun (Springer Nature, 2019-03-05)
      One of the least understood aspects in atmospheric chemistry is how urban emissions influence the formation of natural organic aerosols, which affect Earth's energy budget. The Amazon rainforest, during its wet season, is ...
    • Usability Evaluation in Virtual Environments: Classification and Comparison of Methods 

      Bowman, Doug A.; Gabbard, Joseph L.; Hix, Deborah (Department of Computer Science, Virginia Polytechnic Institute & State University, 2001), TR-01-17
      Virtual environments (VEs) are a relatively new type of human-computer interface in which users perceive and act in a three-dimensional world. The designers of such systems cannot rely solely on design guidelines for ...
    • Usability Inspection Report of iLumina 

      Shivakumar, Priya; Hartson, H. Rex; Perez, Victor M. (Department of Computer Science, Virginia Polytechnic Institute & State University, 2002-09-01), TR-02-20
      iLumina is a digital library of sharable undergraduate teaching resource materials for science, mathematics, technology, and engineering being developed by the University of North Carolina at Wilmington (UNCW), Collegis, ...
    • Usability Inspection Report of NCSTRL 

      Hartson, H. Rex; Shivakumar, Priya (Department of Computer Science, Virginia Polytechnic Institute & State University, 2002-04-01), TR-02-08
      An evaluation report of the www.ncstrl.org site outlining usability problems and solutions to these problems.
    • Usability of Tablet PC as a Remote Control Device for Biomedical Data Visualization 

      Narayan, Michael; Chen, Jian; Pérez-Quiñones, Manuel A. (Department of Computer Science, Virginia Polytechnic Institute & State University, 2004), TR-04-26
      Interaction through multi-platform user interfaces (MPUIs), is increasingly being used in battlefield applications, telemedicine, classroom education, and engineering applications. Some of the uniqueness of these non-traditional ...
    • Use and Usability in a Digital Library Search System 

      France, Robert K.; Nowell, Lucy Terry; Fox, Edward A.; Saad, Rani A.; Zhao, Jianxin (1999)
      Digital libraries must reach out to users from all walks of life, serving information needs at all levels. To do this, they must attain high standards of usability over an extremely broad audience. This paper details the ...
    • Use and Usability in a Digital Library Search System 

      France, Robert K.; Nowell, Lucy Terry; Fox, Edward A.; Saad, Rani A.; Zhao, Jianxin (Virginia Tech Digital Library Research Laboratory, 1999)
      Digital libraries must reach out to users from all walks of life, serving information needs at all levels. To do this, they must attain high standards of usability over an extremely broad audience. This paper details the ...