The ACS Virgo Cluster Survey IV: Data Reduction Procedures for Surface Brightness Fluctuation Measurements with the Advanced Camera for Surveys

The Advanced Camera for Surveys (ACS) Virgo Cluster Survey is a large program to image 100 early-type Virgo galaxies using the F475W and F850LP bandpasses of the Wide Field Channel of the ACS instrument on the Hubble Space Telescope (HST). The scientific goals of this survey include an exploration of the three-dimensional structure of the Virgo Cluster and a critical examination of the usefulness of the globular cluster luminosity function as a distance indicator. Both of these issues require accurate distances for the full sample of 100 program galaxies. In this paper, we describe our data reduction procedures and examine the feasibility of accurate distance measurements using the method of surface brightness fluctuations (SBF) applied to the ACS Virgo Cluster Survey F850LP imaging. The ACS exhibits significant geometrical distortions due to its off-axis location in the HST focal plane; correcting for these distortions by resampling the pixel values onto an undistorted frame results in pixel correlations that depend on the nature of the interpolation kernel used for the resampling. This poses a major challenge for the SBF technique, which normally assumes a flat power spectrum for the noise. We investigate a number of different interpolation kernels and show through an analysis of simulated galaxy images having realistic noise properties that it is possible, depending on the kernel, to measure SBF distances using distortion-corrected ACS images without introducing significant additional error from the resampling. We conclude by showing examples of real image power spectra from our survey.Comment: ApJS, in press, complete version of the paper at the link: http://www.physics.rutgers.edu/~pcote/acs/publications.htm

Film Thickness of Grease in Rolling Contacts

O/)licrrl iirtciferoi~~ctiy is used to stz~lly the film thickness of pccrses, colrl of soap srcspeiuioiu and of their base oils in point or lii,e cwrloct. 111 mze cllse, sa?tiples were taken born a grease-lubriccrtc(l p111.i~~c-Occiring test c$/.er 5%- and 25-million revolutions. The effcc/I'~~c ~~i.scosity of (1 pease t~itder the very high shear rates of the order if 1/2 X lo- " S-I eizcoz~~zl~~~ed in rolling conlack can be cc1./c11ln/ccl

Thermal Analysis of a Special Grout Mixture for In-Situ Decommissioning -11389

ABSTRACT The 105-R Reactor at Savannah River Site (SRS) has been obsolete since 1964. The Department of Energy has set a goal to reduce its footprint at SRS; therefore identifying the 105-R Reactor for decommissioning was made in collaboration with stakeholders. The in-situ decommissioning (ISD) approach was used as the end state for the safe and cost effective disposition of a structurally sound, robust nuclear facility. This decommissioning approach involves filling all below grade areas with flowable, self leveling cementitious materials (grout) to entomb this massive nuclear building. Fill material generates heat (heat of hydration) during the curing process, which may influence material compatibility/stability with the existing structure. Temperature differences can affect the curing properties of the grout as well as cause the material to expand and contract as it heats and cools, which may in turn cause thermal cracking. An experimental setup was performed at the Applied Research Center (ARC) at Florida International University (FIU) in order to monitor the temperature along the radial and axial direction of the grout mixture with respect to time. The experiment focused on determining the presence of localized hot spots and determining the extent of thermal uniformity. The experiment also verified that the compressive strength of the grout was not under the minimum site requirement of 345 kPa (50 psi). Obtaining temperature changes as the grout cured had the additional benefit of providing understanding of the material behavior along the radial direction, which provides an indication of material quality; this is an area which has not been studied thoroughly and, therefore, is of interest to SRNL

A Sensor Classification Scheme

Abstract-We discuss a flexible and comprehensive categorizing scheme that is useful for describing and comparing sensors

Efficiency of short-pulse type-I second-harmonic generation with simultaneous spatial walk-off, temporal walk-off, and pump depletion

Abstract-We have developed a theory which for the first time predicts the efficiency of type-I second-harmonic generation (SHG) with simultaneous spatial and temporal walk-offs and with pump depletion. In order to validate our theory, we have compared its predictions with a numerical solver. We also have measured the conversion efficiency for type-I SHG in experiments with 120-fs laser pulses in BBO and LBO crystals long enough that both temporal and spatial walk-off are important. Comparison supports our theoretical analysis. Our theory provides a useful tool for estimating SHG efficiency with pulsed sources in both nondepletion and depletion regions

Equalization of nonlinear time-varying channels using type-2 fuzzy adaptive filters

Abstract-This paper presents a new kind of adaptive filter: type-2 fuzzy adaptive filter (FAF); one that is realized using an unnormalized type-2 Takagi-Sugeno-Kang (TSK) fuzzy logic system (FLS). We apply this filter to equalization of a nonlinear time-varying channel and demonstrate that it can implement the Bayesian equalizer for such a channel, has a simple structure, and provides fast inference. A clustering method is used to adaptively design the parameters of the FAF. Two structures are used for the equalizer: transversal equalizer (TE) and decision feedback equalizer (DFE). A new decision tree structure is used to implement the decision feedback equalizer, in which each leaf of the tree is a type-2 FAF. This DFE vastly reduces computational complexity as compared to a TE. Simulation results show that equalizers based on type-2 FAFs perform much better than nearest neighbor classifiers (NNC) or equalizers based on type-1 FAFs. Index Terms-Channel equalization, decision feedback equalizer, decision tree, interval type-2 TSK fuzzy logic systems, timevarying channels, type-2 fuzzy adaptive filters

Analysis of historical negative control group data from the in vitro micronucleus assay using human lymphocytes.

A database of the micronuclei counts was built up for historical negative control data from human lymphocyte in vitro micronuclei tests (MnVit) carried out in 8 laboratories with experience of the method. The mean incidence of micronucleated cells (mnt)/1000 cells ranged from 2.2/1000 to 15.9/1000. There were no large differences in incidence between the presence or absence of S9 mix or between different treatment lengths. There was also little evidence that different solvents affected the numbers of micronuclei appreciably. A number of laboratories did show significant inter-experiment variability, indicating that there remained unidentified factors affecting frequencies. Donor variance may be one such factor. Inter-individual variability may explain some of these differences. The approximate 7.5-fold difference in mnt/1000 scores in a relatively small group of experienced laboratories illustrates the potential complications that can arise if a metric like a fold increase was considered the only biologically important finding. Although there is inherent variability between experiments, it was evident that within a laboratory the overall laboratory mean remains constant over time. It is believed that these findings will provide help to laboratories conducting studies using human lymphocytes in the MnVit and to those involved in the assessment of MnVit results

A Bound on the Financial Value of Information

Abstract --It will be shown that each bit of information at most doubles the resulting wealth in the general stock market setup. This information bound on the growth of wealth is actually' attained for certain probability distributions on the market investigated by Kelly. The bound will be shown to be a special case of the result that the increase in exponential growth of wealth achieved with true knowledge of the stock market distribution F over that achieved with incorrect knowledge G is bounded above by D( FllG), the entropy of F relative to G

Flow-Velocity Measurement for Bulk Granular Solids in Pneumatic Conveyor Pipes Using Random-Data Correlator Architecture

Abstract-This paper discusses a correlative-measurement technique for the evaluation of the flow velocity of bulk granular solids moving through the pneumatic conveyor pipes in both the dense and dilute phases. Flow velocities are recovered from the cross-correlation functions between the pairs of signals produced by the noninvasive capacitive sensors placed in circular layers at a given distance on the conveyor pipe. A random-data correlator architecture is discussed as a cost-effective solution for the real-time computation of the multiple correlation functions used for the estimation of the cross-sectional tomographic model of the flow-velocity profile in the dilute phase. Index Terms-Dense phase, dilute phase, particle flow velocity, pneumatic transport of bulk granular solids, random-data correlator architecture