Volume 241, Issue13 (November 2004)
Articles in the Current Issue:
Rapid Research Note
Strong Eu emission of annealed Y2O3:Eu nanotube and nano-sized crystals
NASA Astrophysics Data System (ADS)
Sekita, Masami; Iwanaga, Kenichi; Hamasuna, Tomomi; Mohri, Shinji; Uota, Masafumi; Yada, Mitsunori; Kijima, Tsuyoshi
2004-11-01
We have observed a drastic increase of the Eu3+ emission intensity by annealing nanotubes and nano-sized hexagonal-mesostructured crystals of the Y2O3:Eu system together with bulk samples. It is found that there are three Eu3+ sites in all samples. Stark splitting schemes are proposed for the three homogeneous sites.
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Volume 201, Issue13 (October 2004)
Articles in the Current Issue:
Rapid Research Note
Scintillation properties of lead tungstate crystals doped with the monovalent ion lithium
NASA Astrophysics Data System (ADS)
Huang, Yanlin; Seo, Hyo Jin; Zhu, Wenliang
2004-10-01
Lithium-doped PbWO4 crystals have been grown by the Czochralski method. Optical absorbance, X-ray excited luminescence, light yield measurements and X-ray pulsed excited decays have been investigated. Li+ doping has a very good uniformity and could enhance the luminescence of PbWO4, give some contributions to the fast decay components.
NASA Astrophysics Data System (ADS)
Ivković, Zoran; Lloyd, Errol L.
Classic bin packing seeks to pack a given set of items of possibly varying sizes into a minimum number of identical sized bins. A number of approximation algorithms have been proposed for this NP-hard problem for both the on-line and off-line cases. In this chapter we discuss fully dynamic bin packing, where items may arrive (Insert) and depart (Delete) dynamically. In accordance with standard practice for fully dynamic algorithms, it is assumed that the packing may be arbitrarily rearranged to accommodate arriving and departing items. The goal is to maintain an approximately optimal solution of provably high quality in a total amount of time comparable to that used by an off-line algorithm delivering a solution of the same quality.
FLAMMABLE GAS TECHNICAL BASIS DOCUMENT
DOE Office of Scientific and Technical Information (OSTI.GOV)
KRIPPS, L.J.
2005-02-18
This document describes the qualitative evaluation of frequency and consequences for double shell tank (DST) and single shell tank (SST) representative flammable gas accidents and associated hazardous conditions without controls. The evaluation indicated that safety-significant SSCs and/or TSRS were required to prevent or mitigate flammable gas accidents. Discussion on the resulting control decisions is included. This technical basis document was developed to support of the Tank Farms Documented Safety Analysis (DSA) and describes the risk binning process for the flammable gas representative accidents and associated represented hazardous conditions. The purpose of the risk binning process is to determine the needmore » for safety-significant structures, systems, and components (SSC) and technical safety requirement (TSR)-level controls for a given representative accident or represented hazardous condition based on an evaluation of the event frequency and consequence.« less
Dereplication, Aggregation and Scoring Tool (DAS Tool) v1.0
DOE Office of Scientific and Technical Information (OSTI.GOV)
SIEBER, CHRISTIAN
Communities of uncultivated microbes are critical to ecosystem function and microorganism health, and a key objective of metagenomic studies is to analyze organism-specific metabolic pathways and reconstruct community interaction networks. This requires accurate assignment of genes to genomes, yet existing binning methods often fail to predict a reasonable number of genomes and report many bins of low quality and completeness. Furthermore, the performance of existing algorithms varies between samples and biotypes. Here, we present a dereplication, aggregation and scoring strategy, DAS Tool, that combines the strengths of a flexible set of established binning algorithms. DAS Tools applied to a constructedmore » community generated more accurate bins than any automated method. Further, when applied to samples of different complexity, including soil, natural oil seeps, and the human gut, DAS Tool recovered substantially more near-complete genomes than any single binning method alone. Included were three genomes from a novel lineage . The ability to reconstruct many near-complete genomes from metagenomics data will greatly advance genome-centric analyses of ecosystems.« less
ERIC Educational Resources Information Center
McGuire, Daniel C.
1987-01-01
Describes a project centering around earthworm activity in a compost bin. Includes suggestions for exercises involving biological and conservation concepts, gardening skills, and dramatical presentations. (ML)
Qatar: Background and U.S. Relations
2014-01-30
Industry Mohammed bin Saleh al Sada Minister of State for Defense Affairs MG Hamad bin Ali Al Attiyah Chief of Staff, Qatari Armed Forces MG Ghanim bin...May 2008 after concerns about voter franchise extension were resolved.5 The Advisory Council would have oversight authority over the Council of...have a more lasting impact on the region, but has challenged the traditional Qatari preference for remaining engaged with all sides in regional
Afghanistan, the Taliban, and Osama bin Laden: The Background to September 11
ERIC Educational Resources Information Center
Social Education, 2011
2011-01-01
On May 1, 2011, a group of U.S. soldiers boarded helicopters at a base in Afghanistan, hoping to find a man named Osama bin Laden. Bin Laden, the leader of the al Qaeda terrorist network, was responsible for a number of terrorist attacks around the world, including those of September 11, 2001, that killed nearly 3,000 people in the United States.…
Huang, Jr-Chuan; Lee, Tsung-Yu; Teng, Tse-Yang; Chen, Yi-Chin; Huang, Cho-Ying; Lee, Cheing-Tung
2014-01-01
The exponent decay in landslide frequency-area distribution is widely used for assessing the consequences of landslides and with some studies arguing that the slope of the exponent decay is universal and independent of mechanisms and environmental settings. However, the documented exponent slopes are diverse and hence data processing is hypothesized for this inconsistency. An elaborated statistical experiment and two actual landslide inventories were used here to demonstrate the influences of the data processing on the determination of the exponent. Seven categories with different landslide numbers were generated from the predefined inverse-gamma distribution and then analyzed by three data processing procedures (logarithmic binning, LB, normalized logarithmic binning, NLB and cumulative distribution function, CDF). Five different bin widths were also considered while applying LB and NLB. Following that, the maximum likelihood estimation was used to estimate the exponent slopes. The results showed that the exponents estimated by CDF were unbiased while LB and NLB performed poorly. Two binning-based methods led to considerable biases that increased with the increase of landslide number and bin width. The standard deviations of the estimated exponents were dependent not just on the landslide number but also on binning method and bin width. Both extremely few and plentiful landslide numbers reduced the confidence of the estimated exponents, which could be attributed to limited landslide numbers and considerable operational bias, respectively. The diverse documented exponents in literature should therefore be adjusted accordingly. Our study strongly suggests that the considerable bias due to data processing and the data quality should be constrained in order to advance the understanding of landslide processes.
Weighted Statistical Binning: Enabling Statistically Consistent Genome-Scale Phylogenetic Analyses
Bayzid, Md Shamsuzzoha; Mirarab, Siavash; Boussau, Bastien; Warnow, Tandy
2015-01-01
Because biological processes can result in different loci having different evolutionary histories, species tree estimation requires multiple loci from across multiple genomes. While many processes can result in discord between gene trees and species trees, incomplete lineage sorting (ILS), modeled by the multi-species coalescent, is considered to be a dominant cause for gene tree heterogeneity. Coalescent-based methods have been developed to estimate species trees, many of which operate by combining estimated gene trees, and so are called "summary methods". Because summary methods are generally fast (and much faster than more complicated coalescent-based methods that co-estimate gene trees and species trees), they have become very popular techniques for estimating species trees from multiple loci. However, recent studies have established that summary methods can have reduced accuracy in the presence of gene tree estimation error, and also that many biological datasets have substantial gene tree estimation error, so that summary methods may not be highly accurate in biologically realistic conditions. Mirarab et al. (Science 2014) presented the "statistical binning" technique to improve gene tree estimation in multi-locus analyses, and showed that it improved the accuracy of MP-EST, one of the most popular coalescent-based summary methods. Statistical binning, which uses a simple heuristic to evaluate "combinability" and then uses the larger sets of genes to re-calculate gene trees, has good empirical performance, but using statistical binning within a phylogenomic pipeline does not have the desirable property of being statistically consistent. We show that weighting the re-calculated gene trees by the bin sizes makes statistical binning statistically consistent under the multispecies coalescent, and maintains the good empirical performance. Thus, "weighted statistical binning" enables highly accurate genome-scale species tree estimation, and is also statistically consistent under the multi-species coalescent model. New data used in this study are available at DOI: http://dx.doi.org/10.6084/m9.figshare.1411146, and the software is available at https://github.com/smirarab/binning. PMID:26086579
Efficient visibility-driven medical image visualisation via adaptive binned visibility histogram.
Jung, Younhyun; Kim, Jinman; Kumar, Ashnil; Feng, David Dagan; Fulham, Michael
2016-07-01
'Visibility' is a fundamental optical property that represents the observable, by users, proportion of the voxels in a volume during interactive volume rendering. The manipulation of this 'visibility' improves the volume rendering processes; for instance by ensuring the visibility of regions of interest (ROIs) or by guiding the identification of an optimal rendering view-point. The construction of visibility histograms (VHs), which represent the distribution of all the visibility of all voxels in the rendered volume, enables users to explore the volume with real-time feedback about occlusion patterns among spatially related structures during volume rendering manipulations. Volume rendered medical images have been a primary beneficiary of VH given the need to ensure that specific ROIs are visible relative to the surrounding structures, e.g. the visualisation of tumours that may otherwise be occluded by neighbouring structures. VH construction and its subsequent manipulations, however, are computationally expensive due to the histogram binning of the visibilities. This limits the real-time application of VH to medical images that have large intensity ranges and volume dimensions and require a large number of histogram bins. In this study, we introduce an efficient adaptive binned visibility histogram (AB-VH) in which a smaller number of histogram bins are used to represent the visibility distribution of the full VH. We adaptively bin medical images by using a cluster analysis algorithm that groups the voxels according to their intensity similarities into a smaller subset of bins while preserving the distribution of the intensity range of the original images. We increase efficiency by exploiting the parallel computation and multiple render targets (MRT) extension of the modern graphical processing units (GPUs) and this enables efficient computation of the histogram. We show the application of our method to single-modality computed tomography (CT), magnetic resonance (MR) imaging and multi-modality positron emission tomography-CT (PET-CT). In our experiments, the AB-VH markedly improved the computational efficiency for the VH construction and thus improved the subsequent VH-driven volume manipulations. This efficiency was achieved without major degradation in the VH visually and numerical differences between the AB-VH and its full-bin counterpart. We applied several variants of the K-means clustering algorithm with varying Ks (the number of clusters) and found that higher values of K resulted in better performance at a lower computational gain. The AB-VH also had an improved performance when compared to the conventional method of down-sampling of the histogram bins (equal binning) for volume rendering visualisation. Copyright © 2016 Elsevier Ltd. All rights reserved.
BAO from Angular Clustering: Optimization and Mitigation of Theoretical Systematics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Crocce, M.; et al.
We study the theoretical systematics and optimize the methodology in Baryon Acoustic Oscillations (BAO) detections using the angular correlation function with tomographic bins. We calibrate and optimize the pipeline for the Dark Energy Survey Year 1 dataset using 1800 mocks. We compare the BAO fitting results obtained with three estimators: the Maximum Likelihood Estimator (MLE), Profile Likelihood, and Markov Chain Monte Carlo. The MLE method yields the least bias in the fit results (bias/spreadmore » $$\\sim 0.02$$) and the error bar derived is the closest to the Gaussian results (1% from 68% Gaussian expectation). When there is mismatch between the template and the data either due to incorrect fiducial cosmology or photo-$z$ error, the MLE again gives the least-biased results. The BAO angular shift that is estimated based on the sound horizon and the angular diameter distance agree with the numerical fit. Various analysis choices are further tested: the number of redshift bins, cross-correlations, and angular binning. We propose two methods to correct the mock covariance when the final sample properties are slightly different from those used to create the mock. We show that the sample changes can be accommodated with the help of the Gaussian covariance matrix or more effectively using the eigenmode expansion of the mock covariance. The eigenmode expansion is significantly less susceptible to statistical fluctuations relative to the direct measurements of the covariance matrix because the number of free parameters is substantially reduced [$p$ parameters versus $p(p+1)/2$ from direct measurement].« less
Failure Detection of a Pseudolite-Based Reference System Using Residual Monitoring
2009-03-01
inertial measurements contain white Gaussian noise, wfins and w ! ins. f bins = f b + abias + w f ins (2.3) !bibins = ! b ib + !bias + w ! ins (2.4) A...type of IMU being used and the length of navigation. For a more accurate model the bias can estimated as a drift, shown as abias and !bias. The drift...to be estimated inside a Kalman lter. _abias = abias T + wabias (2.5) where T is the time constant. The strapdown mechanization for raw inertial
Community Detection in Sparse Random Networks
2013-08-13
if, (i, j) ∈ E , meaning there is an edge between nodes i, j ∈ V. Note that W is symmetric, and we assume that Wii = 0 for all i. Under the null... Wii = 0.) Our arguments are parallel to those we used under P0, the only difficulty being that Wi is not binomial anymore. Indeed, WSi ∼ Bin(n − 1, p1...Berlin: Springer. Alon, N. and S. Gutner (2010). Balanced families of perfect hash functions and their applications. ACM Trans. Algorithms 6 (3), Art
ERIC Educational Resources Information Center
Al-Khateeb, Omar; Alrub, Mohammad Abo
2015-01-01
This study aimed to find out how the effectiveness of the curriculum biography of the Prophet in the development of social intelligence skills of Al-Hussein Bin Talal University students and the study sample consisted of 365 students from Al-Hussein Bin Talal University for the first semester 2014-2015 students were selected in accessible manner.…
Nuclear Terrorism: Assessing the Threat, Developing a Response
2009-01-01
these weapons fit within bin Laden’s worldview: Since the late 1980s and certainly since 1991, bin Laden has seen the United States as the principal...leaders and its current senior managers, including bin Laden, Zawahiri, and their key lieutenants; > A number of affiliated groups or “ franchises ...source of danger appears to have shifted toward the independent and quasi-independent franchises as well as local extremists.73 As a result of this
Ain't No Neuroscience Mountain High Enough: Experiences of a Neurogardener.
Abdullah, Jafri Malin
2015-01-01
16 years have passed since the idea was mooted in 1999 by five neurosurgeons in the corridors of Hotel Perdana, Kota Bharu. They were Dato' Dr Johari Siregar Bin Adnan, Dato' Professor Dr Ahmad Zubaidi Abdul Latif , Dr Azmin Kass Bin Rosman, Dato' Dr Mohammed Saffari Bin Mohammed Haspani and Professor Dato' Dr Jafri Malin Abdullah. They initiated the beginning of the first programme in Neurosurgery in Malaysia. The rest is history.
