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Displaying 27026 - 27050 of 73929

Privacy-Preserving DRM

April 13, 2010
Author(s)
Radia Perlman, Charles Kaufman, Ray Perlner
This paper describes and contrasts two families of schemes that enable a user to purchase digital content without revealing to anyone what item he has purchased. One of the basic schemes is based on anonymous cash, and the other on blind decryption. In

Near-Field Antenna as a Scanning Microwave Probe for Characterization of Materials and Devices

April 12, 2010
Author(s)
Atif A. Imtiaz, Thomas M. Wallis, SangHyun S. Lim, Jonathan Chisum, Zoya Popovic, Pavel Kabos
The Scanning Microwave Probe (SMP) is emerging as an important broadband metrology tool for characterizing the materials and devices in the micron and sub-micron length scales in the frequency range of 10 MHz to 110 GHz. In this document we establish three

Parametric Study on the use of Reverberation Chambers for Repeatable/Controllable Wireless Testing: Application to BER Measurements

April 12, 2010
Author(s)
Christopher L. Holloway, E Genender, Catherine A. Remley, John M. Ladbury, Galen H. Koepke
We illustrate use of the reverberation chamber to simulate different wireless propagation environments including effects such as narrowband or frequency-selective fading and Doppler spread. These effects have a strong impact on the quality of the wireless

RECIST vs. Volume Measurement in Medical CT Using Ellipsoids of Known Size

April 12, 2010
Author(s)
Zachary H. Levine, Bruce R. Borchardt, Nolan J. Brandenburg, Charles W. Clark, Balasubramanian Muralikrishnan, Craig M. Shakarji, Joseph J. Chen, Eliot L. Siegel
(a) Purpose: We wanted to test the extent to which two common methods of determining the sizes of tumors would perform when compared to a statistically significant number of well-characterized reference objects. The size of the objects was chosen to

ZigBee-Wireless Mesh Networks for Building Automation and Control

April 12, 2010
Author(s)
Wenqi Guo, William M. Healy, Mengchu Zhou
ZigBee is a wireless technology developed as an open global standard to address the unique needs of low-cost low-power wireless sensor networks. This standard takes full advantages of the IEEE 802.15.4 physical radio specification and operates in

Properties of Injectable Apatite-Forming Premixed Cements

April 10, 2010
Author(s)
Yasushi Shimada, Laurence Chow, Shozo Takagi, Junji Tagami
A previously reported, premixed calcium phosphate cements (CPC) forms hydroxyapatite (HA) as the only product, but had a setting time greater than 60 min. This study investigated properties of fast-hardening HA-forming premixed CPCs. All cements consisted

Computational Analysis of Dynamic SPK(S8)-JP8 Fueled Combustor-Sector Performance

April 9, 2010
Author(s)
R. Ryder, Robert C. Hendricks, Marcia L. Huber, D. T. Shouse
Civil and military flight tests using blends of synthetic and biomass fueling with jet fuel up to 50:50 are currently considered as drop in fuels. They are fully compatible with aircraft performance, emissions and fueling systems, yet the design and

Results from a Full-Scale Smoke Alarm Sensitivity Study

April 9, 2010
Author(s)
Thomas G. Cleary
A series of 24 full-scale experiments was conducted to examine the effects of alarm type (photoelectric, ionization, and dual sensor), alarm location, fabric type (100% cotton and 100% polyester), polyurethane foam density, ignition scenario, and room

A Semantic Product Modeling Framework and Language for Behavior Evaluation

April 8, 2010
Author(s)
Jae H. Lee, Hyo Won Suh, Steven J. Fenves, Sudarsan Rachuri, Xenia Fiorentini, Ram D. Sriram, Conrad E. Bock
Supporting different stakeholder viewpoints across the product's entire lifecycle requires semantic richness for representing product related information. This paper proposes a multi-layered product modeling framework that enables stakeholders to define

A Numerical Study of the Flow of Bingham-Like Fluids In Two Dimensional Vane And Cylinder Rheometers Using a Smoothed Particle Hydrodynamic (SPH) Based Method

April 7, 2010
Author(s)
Huaning Zhu, Nicos Martys, Chiara C. Ferraris, Daniel De Kee
A vane rheometer is commonly used to determine the rheological properties of suspensions, colloids such as cement-based materials, many of which can be described as a Bingham fluid. Due to the complex flow geometry of the vane rheometer, relating measured

How often and how long should a cognitive radio sense the spectrum?

April 7, 2010
Author(s)
Nader Moayeri
This paper presents a Bayesian framework and a pricing structure for a secondary wireless user that opportunistically uses a RF channel belonging to a network of N primary users. The secondary user operates in a time-slotted fashion, where each time slot

Modeling of the Temperature Field in the Chip and in the Tool in High-speed Machining of a Carbon Steel: Effect of Pearlite to Austenite Phase Transition in AISI 1075

April 7, 2010
Author(s)
Timothy J. Burns, Steven P. Mates, Richard L. Rhorer, Eric P. Whitenton, Debasis Basak, Russell H. McFadden
A one-dimensional transient finite-difference model for the temperature distribution in orthogonal metal cutting, which was originally developed by Boothroyd, and then improved upon by Tlusty, is used to calculate the temperature field in the chip and in

Multi-level Spectroscopy of Two-Level Systems Coupled to a dc SQUID Phase Qubit

April 7, 2010
Author(s)
T. A. Palomaki, S. K. Dutta, R M. Lewis, A J. Przybysz, B. K. Cooper, H. Kwon, J. R. Anderson, C. J. Lobb, F. C. Wellstood, Eite Tiesinga
We report spectroscopic measurements of discrete two-level systems (TLSs) coupled to a dc SQUID phase qubit with a 16 μm2 area Al/AlOx/Al junction. Applying microwaves in the 10 GHz to 11 GHz range, we found eight avoided level crossings with splitting

Origin of Electric Field Induced Magnetization in Multiferroic HoMnO 3

April 7, 2010
Author(s)
Benjamin Ueland, Jeffrey W. Lynn, Mark Laver, Y. J. Choi, S.-W. Cheong
We have performed polarized and unpolarized small angle neutron scattering experiments on single crystals of HoMnO 3 and have found that an increase in magnetic scattering at low momentum transfers begins upon cooling through temperatures close to the spin

TESTING OF RESIDENTIAL HOMES UNDER WIND LOADS

April 7, 2010
Author(s)
Emil Simiu, Girma Bitsuamlak, Arindam Chowdury, Ruilong Li, Amanuel Tecle, Dong Hun Yeo
Aerodynamic testing of low-rise structures is fraught with difficulties that can be the cause of large measurement errors resulting in the underestimation of aerodynamic pressures by a factor of as much as two. The errors are due in large part to the

The A 2E" - X 2A2' Transition of NO 3 Trapped in Solid Neon

April 7, 2010
Author(s)
Marilyn E. Jacox, Warren E. Thompson
NO3 has been stabilized in a neon matrix at 4.3 K in sufficient yield for detection of the absorptions between 7000 and 10000 cm-1 which arise from vibronically allowed transitions from its ground state to levels of the A 2E" state. The results confirm and

Ultra Sensitive NIR Spectrometer Based on Frequency Up-conversion Detector

April 7, 2010
Author(s)
Lijun Ma, Oliver T. Slattery, Xiao Tang
We developed a spectrometer for signals at single photon levels in the near infrared (NIR) region based on a tunable up-conversion detector. This detector uses a 5-cm periodically poled lithium niobate (PPLN) waveguide to convert NIR photons to a shorter

Teeth: Among Nature's Most Durable Biocomposites

April 6, 2010
Author(s)
Brian R. Lawn, James J. Lee, H Chai
This paper addresses the durability of natural teeth from a materials perspective. Teeth are depicted as 'smart' biocomposites, highly resistant to cumulative deformation and fracture. Favorable morphological features of teeth at both macroscopic and

Development of Miniature, High Frequency Pulse Tube Cryocoolers

April 5, 2010
Author(s)
Ray Radebaugh, Isaac Garaway, Alexander Veprik
Because acoustic power density is proportional to frequency, the size of pulse tube cryocoolers for a given refrigeration power can be reduced by operating them at higher frequencies. A frequency of about 60 Hz had been considered the maximum frequency
Displaying 27026 - 27050 of 73929
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