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The Composite OLAP-Object Data Model

Description: In this paper, we define an OLAP-Object model that combines the main characteristics of OLAP and Object data models in order to achieve their functionalities in a common framework. We classify three different object classes: primitive, regular and composite. Then, we define a query language which uses the path concept in order to facilitate data navigation and data manipulation. The main feature of the proposed language is an anchor. It allows us to fix dynamically an object class (primitive, r… more
Date: December 7, 2005
Creator: Pourabbas, Elaheh & Shoshani, Arie
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

MATERIAL QUALITY CHARACTERIZATION OF CDZNTE SUBSTRATES FOR HGCDTE EPITAXY.

Description: CdZnTe (CZT) has been traditionally used as substrate for HgCdTe (MCT) epitaxy. The constraint of good lattice matching plays a fundamental role in the use of this substrate. In, fact, despite the difficulties in growing large area of affordable high-quality substrates, CZT wafers remain the best choice for high yield infrared devices. Nevertheless, material quality of the substrate and epilayer play a limiting role in IR focal plane array (FPA) detector technology. Furthermore, data suggest th… more
Date: August 18, 2005
Creator: Carini, G. A.; Bolotnikov, A. E.; Camarda, G. S.; James, R. B. & AL., ET
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Effect of Te Precipitates on the Performance of CdZnTe Detectors.

Description: A recent study of long-drift CdZnTe (CZT) Frisch-ring detectors showed that fluctuations of the collected charge (and device response) depend on the device dimensions and the concentration of Te precipitates in the material. This observation, which could be explained as the cumulative effect of precipitates, led to the investigation of thin (1 mm) planar detectors, where the effects of precipitates can be more clearly ascertained. To perform the investigation, a measurement facility was develop… more
Date: September 20, 2005
Creator: Carini, G. A.; Bolotnikov, A. E.; Camarda, G. S.; Wright, G. W.; Li, L. & James, R. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Electrical activation and spin coherence of ultra low doseantimony implants in silicon

Description: We implanted ultra low doses (0.2 to 2 x 10{sup 11} cm{sup -2}) of Sb ions into isotopically enriched {sup 28}Si, and probed electrical activation and electron spin relaxation after rapid thermal annealing. Strong segregation of dopants towards both Si{sub 3}N{sub 4} and SiO{sub 2} interfaces limits electrical activation. Pulsed Electron Spin Resonance shows that spin echo decay is sensitive to the dopant profiles, and the interface quality. A spin decoherence time, T{sub 2}, of 1.5 ms is found… more
Date: July 13, 2005
Creator: Schenkel, T.; Tyryshkin, A. M.; de Sousa, R.; Whaley, K. B.; Bokor, J.; Liddle, J. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

OSKI: A Library of Automatically Tuned Sparse Matrix Kernels

Description: The Optimized Sparse Kernel Interface (OSKI) is a collection of low-level primitives that provide automatically tuned computational kernels on sparse matrices, for use by solver libraries and applications. These kernels include sparse matrix-vector multiply and sparse triangular solve, among others. The primary aim of this interface is to hide the complex decision-making process needed to tune the performance of a kernel implementation for a particular user's sparse matrix and machine, while al… more
Date: July 19, 2005
Creator: Vuduc, R; Demmel, J W & Yelick, K A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Intelligent Monitoring System With High Temperature Distributed Fiberoptic Sensor For Power Plant Combustion Processes

Description: The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system … more
Date: December 26, 2005
Creator: Lee, Kwang Y.; Yin, Stuart S. & Boheman, Andre
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Executive Correspondence – Letter received 08/08/05 by the BRAC Commission from Princeton University Professor of Electrical Engineering Daniel C. Tsui

Description: Executive Correspondence – Letter received 08/08/05 by the BRAC Commission from Princeton University Professor of Electrical Engineering Daniel C. Tsui criticizing DoD’s recommendation to move the Army Research Office (ARO) from North Carolina to Bethesda, MD and explaining how such a move would severely compromise ARO’s ability to provide revolutionary advances to the Army.
Date: August 11, 2005
Item Type: Refine your search to only Letter
Partner: UNT Libraries Government Documents Department
open access

A WDM/Optical-CDMA (WDM/O-CDMA) Concept for Avionics Integration

Description: We describe a concept where WDM and O-CDMA share a set of discrete wavelengths and components while using similar modulation formats. O-CDMA acts as a channel multiplier. Experiments show the feasibility of >2X channel multiplication.
Date: June 2, 2005
Creator: Mendez, A. J.; Hernandez, V. J.; Gagliardi, R. M.; Braun, S. W.; Bennett, C. V. & Lennon, W. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Feasibility Study for Renewable Energy Development on Tribal Lands

Description: Project Objective: The Mississippi Band of Choctaw Indians (MBCI) conducted a study of the feasibility of siting a renewable energy biomass-based installation on tribal lands. The purpose of the study was to determine whether such an installation can be economically sustainable, as well as consistent with the cultural, social, and economic goals of the Tribe. Scope: To achieve the goal of the feasibility study, the following tasks were carried out: (1) Resource availability assessment--The obje… more
Date: July 21, 2005
Creator: John Hendrix, Project Director; Charles Weir, Project Manager; Dr. John Plodinec, Technology Advisor & Dr. Steve Murray, Economic Advisor
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ion Implantation with Scanning Probe Alignment

Description: We describe a scanning probe instrument which integrates ion beams with the imaging and alignment function of a piezo-resistive scanning probe in high vacuum. The beam passes through several apertures and is finally collimated by a hole in the cantilever of the scanning probe. The ion beam spot size is limited by the size of the last aperture. Highly charged ions are used to show hits of single ions in resist, and we discuss the issues for implantation of single ions.
Date: July 12, 2005
Creator: Persaud, A.; Liddle, J. A.; Schenkel, T.; Bokor, J.; Ivanov, Tzv. & Rangelow, I. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Efficient Modeling of PIN Diode Switches Employing Time-Domain Electromagnetic-Physics-Based Simulators

Description: This paper presents an efficient full-wave time-domain simulator for accurate modeling of PIN diode switches. An equivalent circuit of the PIN diode is extracted under different bias conditions using a drift-diffusion physical model. Net recombination is modeled using a Shockley-Read-Hall process, while generation is assumed to be dominated by impact ionization. The device physics is coupled to Maxwell's equations using extended-FDTD formulism. A complete set of results is presented for the on … more
Date: September 20, 2005
Creator: Hussein, Y. A.; Spencer, J. E.; El-Ghazaly, S. M. & Goodnick, S. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Tracking Vehicles in traffic Surveillance Video

Description: We present a system for detecting and tracking vehicles in surveillance video. Our algorithm uses a simple motion model to determine salient regions in a sequence of video frames. Similar regions are associated between frames and clustered to yield coherent final tracks. The entire process is automatic and uses computation time that scales according to the size of the input video sequence.
Date: August 12, 2005
Creator: Maire, M. & Kamath, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Resist-based measurement of contrast transfer function in a 0.3-NAmicrofield optic

Description: Although extreme ultraviolet (EUV) lithography offers the possibility of very high-resolution patterning, the projection optics must be of extremely high quality in order to meet this potential. One key metric of the projection optic quality is the contrast transfer function (CTF), which is a measure of the aerial image contrast as a function of pitch. A static microfield exposure tool based on the 0.3-NA MET optic and operating at a wavelength of 13.5 nm has been installed at the Advanced Ligh… more
Date: January 11, 2005
Creator: Cain, Jason P.; Naulleau, Patrick & Spanos, Costas J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Critical dimension sensitivity to post-exposure bake temperaturevariation in EUV photoresists

Description: Chemically amplified resists depend upon the post-exposure bake (PEB) process to drive the deprotection reactions (in positive resists) that lead to proper resist development. For this reason they often exhibit critical dimension (CD) sensitivity to PEB temperature variation. In this work the effects of variation in different aspects of the PEB step on post-develop CD are studied for two extreme ultraviolet (EUV) photoresists. The spatial and temporal temperature uniformity of the PEB plate is … more
Date: January 11, 2005
Creator: Cain, Jason P.; Naulleau, Patrick & Spanos, Costas J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Modeling of EUV photoresists with a resist point spreadfunction

Description: Extreme ultraviolet (EUV) lithography is under development for possible deployment at the 32-nm technology node. One active area of research in this field is the development of photoresists that can meet the stringent requirements (high resolution, high sensitivity, low LER, etc.) of lithography in this regime. In order to facilitate research in this and other areas related to EUV lithography, a printing station based upon the 0.3-NA Micro Exposure Tool (MET) optic was established at the Advanc… more
Date: January 1, 2005
Creator: Cain, Jason P.; Naulleau, Patrick & Spanos, Costas J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Chemical states and electronic structure of a HfO(-2) / Ge(001) interface

Description: We report the chemical bonding structure and valence band alignment at the HfO{sub 2}/Ge (001) interface by systematically probing various core level spectra as well as valence band spectra using soft x-rays at the Stanford Synchrotron Radiation Laboratory. We investigated the chemical bonding changes as a function of depth through the dielectric stack by taking a series of synchrotron photoemission spectra as we etched through the HfO{sub 2} film using a dilute HF-solution. We found that a ver… more
Date: May 4, 2005
Creator: Seo, Kang-ill; McIntyre, Paul C.; /Stanford U., Materials Sci. Dept.; Sun, Shiyu; Lee, Dong-Ick; Pianetta, Piero et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Integration of scanning probes and ion beams

Description: We report the integration of a scanning force microscope with ion beams. The scanning probe images surface structures non-invasively and aligns the ion beam to regions of interest. The ion beam is transported through a hole in the scanning probe tip. Piezoresistive force sensors allow placement of micromachined cantilevers close to the ion beam lens. Scanning probe imaging and alignment is demonstrated in a vacuum chamber coupled to the ion beam line. Dot arrays are formed by ion implantation i… more
Date: March 30, 2005
Creator: Persaud, A.; Park, S. J.; Liddle, J. A.; Schenkel, T.; Bokor, J. & Rangelow, I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Two-wave pattern shift aberration monitor for centrally obscuredoptical systems

Description: An aberration monitoring technique based on lateral shifts of two-wave interference patterns in centrally obscured optical systems is presented, and simulations are used to evaluate the performance of such a technique. The technique is being explored as a convenient means for monitoring the aberration level in the 0.3-NA Micro Exposure Tool (MET) optic over time. A binary mask was designed for observing phase differences across the MET optic on cut-lines at 0, 45, 90 and 135 degrees across the … more
Date: January 11, 2005
Creator: Cain, Jason P.; McIntyre, Gregory; Naulleau, Patrick; Pawloski,Adam; La Fontaine, Bruno; Wood, Obert et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

New Results From Testing of Coplanar-Grid CdZnTe Detector.

Description: New results from studies of coplanar-grid CdZnTe (CZT) detectors are presented. The coplanar-grid detectors, were investigated by using a highly collimated X-ray beam available at Brookhaven's National Synchrotron Light Source and by applying a pulse-shape analysis. The coplanar-grid detector operates as a single-carrier device. Despite the fact that its operational principle is well known and has been investigated by many groups in the past, we found some new details that may explain the perfo… more
Date: July 31, 2005
Creator: Carini, G. A. & AL., ET
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Lithographic measurement of EUV flare in the 0.3-NA Micro ExposureTool optic at the Advanced Light Source

Description: The level of flare present in a 0.3-NA EUV optic (the MET optic) at the Advanced Light Source at Lawrence Berkeley National Laboratory is measured using a lithographic method. Photoresist behavior at high exposure doses makes analysis difficult. Flare measurement analysis under scanning electron microscopy (SEM) and optical microscopy is compared, and optical microscopy is found to be a more reliable technique. In addition, the measured results are compared with predictions based on surface rou… more
Date: January 1, 2005
Creator: Cain, Jason P.; Naulleau, Patrick & Spanos, Costas J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Large-Stroke Self-Aligned Vertical Comb Drive Actuators for Adaptive Optics Applications

Description: A high-stroke micro-actuator array was designed, modeled, fabricated and tested. Each pixel in the 4x4 array consists of a self-aligned vertical comb drive actuator. This micro-actuator array was designed to become the foundation of a micro-mirror array that will be used as a deformable mirror for adaptive optics applications. Analytical models combined with CoventorWare{reg_sign} simulations were used to design actuators that would move up to 10{micro}m in piston motion with 100V applied. Devi… more
Date: October 27, 2005
Creator: Carr, E. J.; Olivier, S. S. & Solgaard, O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

On-Line Self-Calibrating Single Crystal Sapphire Optical Sensor Instrumentation for Accurate and Reliable Coal Gasifier Temperature Measurement

Description: This report summarizes technical progress April-September 2005 on the Phase II program ''On-Line Self-Calibrating Single Crystal Sapphire Optical Sensor Instrumentation for Accurate and Reliable Coal Gasifier Temperature Measurement'', funded by the Federal Energy Technology Center of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. The outcome of the first phase of this program… more
Date: November 1, 2005
Creator: Cooper, Kristie; Pickrell, Gary & Wang, Anbo
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

ON-LINE SELF-CALIBRATING SINGLE CRYSTAL SAPPHIRE OPTICAL SENSOR INSTRUMENTATION FOR ACCURATE AND RELIABLE COAL GASIFIER TEMPERATURE MEASUREMENT

Description: This report summarizes technical progress October 2004-March 2005 on the Phase II program ''On-Line Self-Calibrating Single Crystal Sapphire Optical Sensor Instrumentation for Accurate and Reliable Coal Gasifier Temperature Measurement'', funded by the Federal Energy Technology Center of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. The outcome of the first phase of this prog… more
Date: April 1, 2005
Creator: Cooper, Kristie; Pickrell, Gary; Wang, Anbo; Huang, Zhengyu & Zhu, Yizheng
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Wide-Bandgap Semiconductors

Description: With the increase in demand for more efficient, higher-power, and higher-temperature operation of power converters, design engineers face the challenge of increasing the efficiency and power density of converters [1, 2]. Development in power semiconductors is vital for achieving the design goals set by the industry. Silicon (Si) power devices have reached their theoretical limits in terms of higher-temperature and higher-power operation by virtue of the physical properties of the material. To o… more
Date: November 22, 2005
Creator: Chinthavali, M.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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