Now showing items 3274-3293 of 3475

    • The UAN: A User-Oriented Representation for Direct ManipulationInterface Designs 

      Hartson, H. Rex; Siochi, Antonio C.; Hix, Deborah (Department of Computer Science, Virginia Polytechnic Institute & State University, 1990), TR-90-16
      Almost all existing interface representation techniques, especially those associated with UIMS, are constructional, focused on interface implementation, and therefore do not adequately support a user-centered focus. But ...
    • UIMS: Toward the Next Generation 

      Hartson, H. Rex; Hix, Deborah (Department of Computer Science, Virginia Polytechnic Institute & State University, 1986), TR-86-41
      First generation User Interface Management Systems (UIMS) have established themselves in both research and commercial areas. This paper discusses improved usability and extension of UIMS to include a broader whole system ...
    • Ultra-high frequency photoconductivity decay in GaAs/Ge/GaAs double heterostructure grown by molecular beam epitaxy 

      Hudait, Mantu K.; Zhu, Y.; Johnston, S. W.; Maurya, Deepam; Priya, Shashank; Umbel, R. (AIP Publishing, 2013-03-01)
      GaAs/Ge/GaAs double heterostructures (DHs) were grown in-situ using two separate molecular beam epitaxy chambers. High-resolution x-ray rocking curve demonstrates a high-quality GaAs/Ge/GaAs heterostructure by observing ...
    • Ultrahigh electromechanical response in (1-x)(Na0.5Bi0.5)TiO3-xBaTiO(3) single-crystals via polarization extension 

      Ge, Wenwei; Luo, Chengtao; Zhang, Qinhui; Devreugd, Christopher P.; Ren, Yang; Li, Jiefang; Luo, Haosu; Viehland, Dwight D. (American Institute of Physics, 2012-05-01)
      The dielectric, ferroelectric, and electric field-induced strain response of [001]-and [101]-oriented 0.944Na(0.5)Bi(0.5)TiO(3)-0.056BaTiO(3) (0.944NBT-0.056BT) single crystals were investigated as a function of temperature ...
    • Ultrahigh magnetic field sensitivity in laminates of TERFENOL-D and Pb(Mg1/3Nb2/3)O-3-PbTiO3 crystals 

      Dong, Shuxiang; Li, Jiefang; Viehland, Dwight D. (AIP Publishing, 2003-09-01)
      It has been found that laminate composites of longitudinally magnetized magnetostrictive TERFENOL-D and a transversely poled piezoelectric Pb(Mg1/3Nb2/3)O-3-PbTiO3 crystal have extremely high magnetic field sensitivity. ...
    • Ultralow equivalent magnetic noise in a magnetoelectric Metglas/Mn-doped Pb(Mg1/3Nb2/3)O-3-PbTiO3 heterostructure 

      Wang, Yaojin; Gao, Junqi; Li, Menghui; Hasanyan, Davresh J.; Shen, Ying; Li, Jiefang; Viehland, Dwight D.; Luo, Haosu (AIP Publishing, 2012-07-01)
      An ultralow equivalent magnetic noise of 6.2 pT/root Hz at 1 Hz was obtained in a bimorph heterostructure sensor unit consisting of longitudinal-magnetized Metglas layers and a transverse-poled 1 mol. % Mn-doped ...
    • Uncertainty and Probability 

      Nutter, J. Terry (Department of Computer Science, Virginia Polytechnic Institute & State University, 1986), TR-86-36
      Advocates of probability theory as a primary tool for reasoning in contexts of uncertainty and incomplete information have increased in number in recent years. At the same time, opponents have put forward a variety of ...
    • Uncertainty in velocity measurement based on diode-laser absorption in nonuniform flows 

      Li, Fei; Yu, XiLong; Cai, Weiwei; Ma, Lin (Optical Society of America, 2012-07-01)
      This work investigates the error caused by nonuniformities along the line-of-sight in velocity measurement using tunable diode-laser absorption spectroscopy (TDLAS). Past work has demonstrated TDLAS as an attractive ...
    • Uncertainty Quantification and Apportionment in Air Quality Models using the Polynomial Chaos Method 

      Cheng, Haiyan; Sandu, Adrian (Department of Computer Science, Virginia Polytechnic Institute & State University, 2007), TR-07-37
      Simulations of large-scale physical systems are often affected by the uncertainties in data, in model parameters, and by incomplete knowledge of the underlying physics. The traditional deterministic simulations do not ...
    • Uncertainty Quantification for Ti-7Al Alloy Microstructure with an Inverse Analytical Model (AUQLin) 

      Acar, Pınar (MDPI, 2019-05-31)
      The present study addresses an inverse problem for observing the microstructural stochasticity given the variations in the macro-scale material properties by developing an analytical uncertainty quantification (UQ) model ...
    • Under-actuated Controllability for Spacecraft Rendezvous 

      Rogers, Andrew; Woolsey, Craig; McGwier, Robert (Virginia Tech, 2014-06-27)
      In this report, we examine the controllability of a particular form of the equations of motion for spacecraft formation flying. These equations, the Tschauner-Hempel equations, rescale the formation flying equations to a ...
    • Understanding Active Noise Cancellation 

      Kidner, M.R.F. (Hindawi, 2002-01-01)
    • Understanding Ammonium Transport in Bioelectrochemical Systems towards its Recovery 

      Liu, Y; Qin, M; Luo, S; He, Z; Qiao, R (Nature Publishing Group, 2016-03-03)
      We report an integrated experimental and simulation study of ammonia recovery using microbial electrolysis cells (MECs). The transport of various species during the batch-mode operation of an MEC was examined experimentally ...
    • Understanding Application Behaviours for Android Security: A Systematic Characterization 

      Cai, Haipeng; Ryder, Barbara (Department of Computer Science, Virginia Polytechnic Institute & State University, 2016), TR-16-05
      In contrast to most existing research on Android focusing on specific security issues, there is little broad understanding of Android application run-time characteristics and their security implications. To mitigate this ...
    • Understanding Recurring Software Quality Problems of Novice Programmers 

      Techapalokul, Peeratham; Tilevich, Eli (Department of Computer Science, Virginia Polytechnic Institute & State University, 2017-07-12), TR-17-02
      It remains unclear when is the right time to introduce software quality into the computing curriculum. Introductory students often cannot afford to also worry about software quality, while advanced students may have been ...
    • 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 ...