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How to Take Better Photographs: Control Quality by Controlling the Camera

Description: In this Tech Talk presentation, the authors demonstrate simple ways to improve a photograph by making use of camera controls and by considering location, lighting, and composition. The authors will introduce basic information about using manual camera settings to control aperture, shutter speed, and ISO, and the authors will discuss specific "shooting" situations such as portraits, group photos, and events.
Date: July 27, 2011
Creator: Jones, Jerrell & Hall, Nathan
Partner: UNT Libraries
open access

Latest results from the SEMATECH Berkeley extreme ultraviolet microfield exposure tool

Description: Microfield exposure tools (METs) continue to play a dominant role in the development of extreme ultraviolet (EUV) resists. One of these tools is the 0.3 numerical aperture SEMATECH Berkeley MET operating as a resist and mask test center. Here they present an update on the tool summarizing some of the latest test and characterization results. they provide an update on the long-term aberration stability of the tool and present line-space imaging in chemically amplified photoresist down to the 20-… more
Date: September 2, 2008
Creator: Naulleau, Patrick; Anderson, Christopher N.; Chiu, Jerrin; Dean, Kim; Denham, Paul; George, Simi et al.
Partner: UNT Libraries Government Documents Department
open access

Resonant excitation of coupled Rayleigh waves in a short and narrow fluid channel clad between two identical metal plates

Description: This article studies the transmission of ultrasonic waves through a slit between two water immersed brass plates for sub-wavelength plate thicknesses and slit apertures.
Date: July 14, 2014
Creator: Garcia-Chocano, Victor M.; Lopez-Rios, Tomas; Krokhin, Arkadii A. & Sanchez-Dehesa, Jose
Partner: UNT College of Arts and Sciences
open access

Analysis to Determine the Maximum Dimensions of Flexible Apertures in Sensored Security Netting Products.

Description: Although technological advances provide new capabilities to increase the robustness of security systems, they also potentially introduce new vulnerabilities. New capability sometimes requires new performance requirements. This paper outlines an approach to establishing a key performance requirement for an emerging intrusion detection sensor: the sensored net. Throughout the security industry, the commonly adopted standard for maximum opening size through barriers is a requirement based on squar… more
Date: August 1, 2013
Creator: Murton, Mark; Bouchier, Francis A.; vanDongen, Dale T.; Mack, Thomas Kimball; Cutler, Robert Paul & Ross, Michael P.
Partner: UNT Libraries Government Documents Department
open access

Techniques for Identifying and Measuring High Order Modes in RF Cavities

Description: We report on a number of techniques which can be used to unravel the higher-order-mode spectrum of an RF cavity. Most of these techniques involve the application of basic symmetry principles and require for their application only that the cavity exhibit some basic symmetry, possibly broken by the presence of couplers, apertures, etc., which permits a classification of these modes in terms of some property characterized by that symmetry, e.g., multipolarity for a cavity which is basically a figu… more
Date: May 1, 1997
Creator: Goldberg, D.A. & Rimmer, R.A.
Partner: UNT Libraries Government Documents Department
open access

Orbit, optics and chromaticity correction for PS2 negative momentum compaction lattices

Description: The effect of magnet misalignments in the beam orbit and linear optics functions are reviewed and correction schemes are applied to the negative momentum compaction lattice of PS2. Chromaticity correction schemes are also proposed and tested with respect to off-momentum optics properties. The impact of the correction schemes in the dynamic aperture of the lattice is finally evaluated.
Date: May 4, 2009
Creator: Papaphilippou,Y.; Barranco, J.; Bartmann, W.; Benedikt, M.; Carli, C.; De Maria, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Lithographic characterization of low-order aberrations in a 0.3-NAEUV microfield exposure tool

Description: Although tremendous progress has been made in the crucial area of fabrication of extreme ultraviolet (EUV) projection optics, the realization diffraction-limited high numerical aperture (NA) optics (above 0.2 NA) remains a concern. The highest NA EUV optics available to date are the 0.3-NA Microfield Exposure Tool (MET) optics used in an experimental exposure station at Lawrence Berkeley National Laboratory [1] and commercial METs [2] at Intel and SEMATECH-North. Even though these optics have b… more
Date: March 1, 2006
Creator: Naulleau, Patrick; Cain, Jason; Dean, Kim & Goldberg, Kenneth A.
Partner: UNT Libraries Government Documents Department
open access

Comparison of Tevatron C0 and F0 Lambertson beam impedance

Description: Both the longitudinal and transverse beam impedance measurements for the Tevatron C0 and F0 lambertsons are presented. The C0 lambertsons were designed for circulating beam to travel through the 1 inch high by 6 inch wide field region. In the F0 lambertsons, circulating beam passes through the 2.5 inch high by 4 in ch wide field free region. The more recently designed F0 lambertsons have significantly less impedance than the older C0 lambertsons. Transverse impedance scales as one over the diam… more
Date: April 11, 2003
Creator: Fellenz, James L Crisp and Brian
Partner: UNT Libraries Government Documents Department
open access

PDII- Additional discussion of the dynamic aperture

Description: This note is in the nature of an addition to the dynamic aperture calculations found in the report on the Proton Driver, FERMILAB-TM-2169. A extensive discussion of the Proton Driver lattice, as well as the nomenclature used to describe it can be found in TM-2169. Basically the proposed lattice is a racetrack design with the two arcs joined by two long straight sections. The straight sections are dispersion free. Tracking studies were undertaken with the objective of computing the dynamic apert… more
Date: July 23, 2002
Creator: Gelfand, Norman M.
Partner: UNT Libraries Government Documents Department
open access

Aperture limitations for 2nd generation Nb3Sn LHC IR quadrupoles

Description: One of the straightforward ways towards the higher luminosity in the LHC is a replacement of the present 70-mm NbTi quadrupoles with Nb{sub 3}Sn quadrupoles which would provide the same field gradient but in a larger aperture. Conceptual designs of such quadrupoles with 90 mm aperture have been developed and studied. This paper discusses the possibilities and limitations of increasing the aperture of Nb{sub 3}Sn low-beta quadrupoles for a LHC luminosity upgrade up to 110 mm.
Date: June 2, 2003
Creator: Zlobin, Alexander V.; Kashikhin, Vadim V. & Strait, James B.
Partner: UNT Libraries Government Documents Department
open access

Coupling Through Tortuous Path Narrow Slot Apertures into Complex Cavitivies

Description: A hybrid FEM/MoM model has been implemented to compute the coupling of fields into a cavity through narrow slot apertures having depth. The model utilizes the slot model of Warne and Chen [23]-[29] which takes into account the depth of the slot, wall losses, and inhomogeneous dielectrics in the slot region. The cavity interior is modeled with the mixed-order, covariant-projection hexahedral elements of Crowley [32]. Results are given showing the accuracy and generality of the method for modelin… more
Date: July 26, 1999
Creator: Jedlicka, Russell P.; Castillo, Steven P. & Warne, Larry K.
Partner: UNT Libraries Government Documents Department
open access

Finding the Circular Magnet Aperture Which Encloses an Artitrary Number of Midplane-Centered Beam Ellipses.

Description: In specifying the magnets for an accelerator, one must be able to determine the aperture required by the beam. In some machines, in particular FFAGs, there is a significant variation in the closed orbit and beta functions over the energy range of the machine. In addition, the closed orbit and beta functions may vary with the longitudinal position in the magnet. It is necessary to determine a magnet aperture which encloses the beam ellipses at all energies and all positions in the magnet. This p… more
Date: September 14, 2004
Creator: Berg, S. J.
Partner: UNT Libraries Government Documents Department
open access

Nb3Sn Magnets for a Muon Collider

Description: High field dipole and quadrupole magnet designs with racetrack coils are investigated. The design option is particularly attractive for a muon collider dipole magnet using the Nb{sub 3}Sn superconductor. A conceptual design of {approx} 15 T single aperture dipole magnet is presented where the coils maintain a simple 2-d structure through the ends. The use of racetrack coils in quadrupole magnets is also discussed. It appears that the racetrack coils are less attractive for high gradient quadrup… more
Date: June 20, 1998
Creator: Gupta, R. C.; Green, M. A.; Scanlan, R. M. & Palmer, R.
Partner: UNT Libraries Government Documents Department
open access

Status of LHC crab activity simulations and beam studies

Description: The LHC crab cavity program is advancing rapidly towards a first prototype which is anticipated to be tested during the early stages of the LHC phase I upgrade and commissioning. The general project status and some aspects related to crab optics, collimation, aperture constraints, impedances, noise effects. beam transparency and machine protection critical for a safe and robust operation of LHC beams with crab cavities are addressed here.
Date: May 4, 2009
Creator: Calaga, R.; Assman, R.; Barranco, J.; Barranco, J.; Calaga, R.; Caspers, F. et al.
Partner: UNT Libraries Government Documents Department
open access

The SEMATECH Berkeley MET pushing EUV development beyond 22-nm half pitch

Description: Microfield exposure tools (METs) play a crucial role in the development of extreme ultraviolet (EUV) resists and masks, One of these tools is the SEMATECH Berkeley 0.3 numerical aperture (NA) MET, Using conventional illumination this tool is limited to approximately 22-nm half pitch resolution. However, resolution enhancement techniques have been used to push the patterning capabilities of this tool to half pitches of 18 nm and below, This resolution was achieved in a new imageable hard mask wh… more
Date: March 18, 2010
Creator: Naulleau, P.; Anderson, C. N.; Backlea-an, L.-M.; Chan, D.; Denham, P.; George, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Measurement of D->A Momentum Aperture and Test of D->A Field Qualities

Description: The data presented here were taken during two shifts dedicated to D->A studies. The goal during both of these study periods was a test of the field quality of the D->A channel devices, but for the first study period on 10/21/91 the TBT system was not operational so we simply measured the transfer efficiency as a function of momentum. The conclusion from these measurements is as follows: (1) The momentum aperture of the D->A channel is smaller than expected. (2) The restriction is in ph… more
Date: February 27, 1992
Creator: Halling, Mike
Partner: UNT Libraries Government Documents Department
open access

Yttrium Calcium Oxyborate for High Average Power Frequency Doubling and OPCPA

Description: Significant progress has been achieved recently in the growth of Yttrium Calcium Oxyborate (YCOB) crystals. Boules have been grown capable of producing large aperture nonlinear crystal plates suitable for high average power frequency conversion or optical parametric chirped pulse amplification (OPCPA). With a large aperture (5.5 cm x 8.5 cm) YCOB crystal we have demonstrated a record 227 W of 523.5nm light (22.7 J/pulse, 10 Hz, 14 ns). We have also demonstrated the applicability of YCOB for 105… more
Date: June 20, 2006
Creator: Liao, Z. M.; Jovanovic, I.; Ebbers, C. A.; Bayramian, A.; Schaffers, K.; Caird, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Optimization Of Chromaticity Compensation And Dynamic Aperture In MEIC Collider Rings

Description: The conceptual design of the Medium-energy Electron-Ion Collider (MEIC) at Jefferson Lab relies on an ultra-small beta-star to achieve high luminosities of up to 10{sup 34} cm{sup -2} s{sup -1}. A low-beta insertion for interaction regions unavoidably induces large chromatic effects that demand a proper compensation. The present approach of chromatic compensation in the MEIC collider rings is based on a local correction scheme using two symmetric chromatic compensation blocks that includes fami… more
Date: July 1, 2012
Creator: Fanglei Lin, Yaroslav Derbenev, Vasiliy Morozov, Yuhong Zhang, Kevin Beard
Partner: UNT Libraries Government Documents Department
open access

Common Coil Magnet System for VLHC

Description: This paper introduces the common coil magnet system for the proposed very large hadron collider (VLHC). In this system, the high energy booster (HEB), the injector to VLHC, is integrated as the iron dominated low field aperture within the coldmass of the common coil magnet design introduced earlier. This 4-in-1 magnet concept for a 2-in-1 machine should provide a major cost reduction in building and operating VLHC. Moreover, the proposed design reduces the field quality problems associated with… more
Date: February 12, 1999
Creator: Gupta, R.
Partner: UNT Libraries Government Documents Department
open access

Evaluation of the Mathieu Function Series for Diffraction by a Slot

Description: Diffraction of a wave passing through a slot is a fundamental problem that has applications in many situations. A problem of current interest is the propagation of waves through obstacles such as buildings in an urban environment, where an entrance aperture could be approximated as a slot. Solutions for the diffracted fields of a slot have been obtained by exact eigenfunction expansions as well as various approximate and numerical methods. The eigenfunction solution, in terms of Mathieu functio… more
Date: June 15, 2005
Creator: Burke, G J & Pao, H Y
Partner: UNT Libraries Government Documents Department
open access

A calculation of the dynamic aperture of the LHC

Description: The dynamic aperture for version 5.1, with a 300{mu}r crossing angle at IP1 and IP5, of the Large Hadron Collider (LHC) lattice has been estimated using the tracking code TEVLAT. The dynamic aperture calculated here is due to the magnetic field errors in the high gradient quadrupoles (MQX) in the two low-{beta} interaction regions at IR1 and IR5. No errors were assigned to the magnets in the arc regions of the lattice, nor were beam-beam effects incorporated. The dynamic aperture is expressed i… more
Date: April 23, 1999
Creator: Gelfand, Norman M.
Partner: UNT Libraries Government Documents Department
open access

10-kJ Status and 100-kJ Future for NIF PetaWatt Technology

Description: We discuss the status of the NIF ARC, an 8-beam 10-kJ class high-energy petawatt laser, and the future upgrade path of this and similar systems to 100-kJ-class with coherent phasing of multiple apertures.
Date: July 2, 2007
Creator: Siders, C W; Crane, J K; Rushford, M C; Haefner, L C; Hernandez, J E; Dawson, J W et al.
Partner: UNT Libraries Government Documents Department
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