• Title/Summary/Keyword: Benjamin

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USING VIRTUAL OBSERVATORY TOOLS FOR ASTRONOMICAL RESEARCH

  • KIM SANG CHUL;TAYLOR JOHN D.;PANTER BENJAMIN;SOHN SANGMO TONY;HEAVENS ALAN F.;MANN ROBERT G.
    • Journal of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.85-88
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    • 2005
  • Construction of the Virtual Observatory (VO) is a great concern to the astronomical community in the 21st century. We present an outline of the concept and necessity of the va and the current status of various VO projects including the 15 national ones and the International Virtual Observatory Alliance (IVOA). We summarize the possible science cases that could be solved by using the VO data/tools, real science cases which are the results of using current VO tools, and our own work of using AstroGrid, the United Kingdom national VO, for a research on star formation history of galaxies.

Alignments of interacting haloes in the Horizon run 4 simulation

  • L'Huillier, Benjamin;Park, Changbom;Kim, Juhan
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.29.2-29.2
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    • 2015
  • Interactions such as mergers and flybys play a fundamental role in shaping galaxy morphology. We used the Horizon Run 4 cosmological N-body simulations to study the aligments of spins and shapes of interacting haloes as a function of the halo mass and large-scale density. Interactions preferentially occur in the plane of rotation, and in the direction of the major axis of prolate haloes, and the trajectories are preferentially radial and prograde. We found a very strong alignment of the shapes already at redshift as high as 4. The spins are initially unaligned or even anti-aligned, and become more and more aligned as the redshift decreases. The alignment signals are stronger and evolve more at lower densities, and mass plays a secondary role.

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Effects of the Initial Conditions on Cosmological N-body Simulations

  • L'Huillier, Benjamin;Park, Changbom;Kim, Juhan
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.57.2-57.2
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    • 2013
  • Cosmology is entering an era of percent precision with large surveys, demanding accurate simulations. In this paper, we aim to study the effects of initial conditions on the results of cosmological simulations, which will help us to make percent-level accuracy simulations. For this purpose, we use a series of cosmological N-body simulations with varying initial conditions. We test the influence of the initial conditions, namely the pre-initial configuration (preIC), the order of the perturbation theory, and the initial redshift, on the statistics associated with the large scale structures of the universe such as the halo mass function, the density power spectrum, and the maximal extent of the large scale structures. We find that glass or grid pre-initial conditions give similar results. However, the order of the Lagrangian perturbation theory used to generate the initial conditions and the starting epoch of the simulations play a crucial role, especially at high redshift (z ~ 2-4). The initial conditions have to be chosen with care, taking into account the specificity of the simulation.

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Performance Evaluation of Gas Cleaning Industrial Filters using a Bi-Modal Test Aerosol for Dust Loading Studies

  • Lee, Jae-Keun;Kim, Seong-Chan;Benjamin Y.H. Liu
    • Journal of Energy Engineering
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    • v.5 no.2
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    • pp.131-137
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    • 1996
  • Typical size distribution of emission particulates is bi-modal in shape with particles in the fine mode (< 2.0 $\mu\textrm{m}$) and the coarse mode. An experimental study of pressure drop across the industrial gas cleaning filters has been conducted using particle mixture of fine alumina and coarse Arizona dusts with a rotating aerosol disperser to generate the bi-modal test aerosol. Pressure drop increased linearly with increasing mass loading. The pressure drop was found to be strongly dependent upon the mass ratio of fine to coarse particles. The smaller the mass ratio of fine to coarse particles and the higher face velocity are, the faster pressure drop rises. The fine particles and the greater inertia of the particle moving fast would cause a denser cake formation on the filter surface, resulting in a greater specific resistance to the gas flow.

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Identification of Chinese Personal Names in Unrestricted Texts

  • Cheung, Lawrence;Tsou, Benjamin K.;Sun, Mao-Song
    • Proceedings of the Korean Society for Language and Information Conference
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    • 2002.02a
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    • pp.28-35
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    • 2002
  • Automatic identification of Chinese personal names in unrestricted texts is a key task in Chinese word segmentation, and can affect other NLP tasks such as word segmentation and information retrieval, if it is not properly addressed. This paper (1) demonstrates the problems of Chinese personal name identification in some If applications, (2) analyzes the structure of Chinese personal names, and (3) further presents the relevant processing strategies. The geographical differences of Chinese personal names between Beijing and Hong Kong are highlighted at the end. It shows that variation in names across different Chinese communities constitutes a critical factor in designing Chinese personal name Identification algorithm.

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Anatomic landmark approach to reconstruction of asymmetric midline cleft lip due to Pai syndrome

  • Sobol, Danielle L.;Massenburg, Benjamin B.;Tse, Raymond W.
    • Archives of Plastic Surgery
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    • v.47 no.5
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    • pp.483-486
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    • 2020
  • Midline clefts of the upper lip are rare, and it is therefore important that surgeons have access to a methodical approach for when these presentations are encountered. We adapted principles of the anatomic subunit approximation for unilateral cleft lip, to the repair of midline clefts. The overt use of anatomic landmarks to define the repair results in a design that inherently adjusts to varying degrees of clefts and can accommodate asymmetries. The "measure twice, cut once" style is an advantage to new surgeons and to surgeons who seldom encounter this presentation. We describe the details of surgical repair in the context of a patient with Pai syndrome and associated nasal hamartomas that resulted in nasolabial asymmetry. This is the first report of surgical outcome following treatment of Pai syndrome and includes early and 5-year follow-up. The system of repair that we describe is applicable to both symmetric and asymmetric midline clefts.

Experimental and numerical analysis of corrosion-induced cover cracking in reinforced concrete sample

  • Richard, Benjamin;Quiertant, Marc;Bouteiller, Veronique;Delaplace, Arnaud;Adelaide, Lucas;Ragueneau, Frederic;Cremona, Christian
    • Computers and Concrete
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    • v.18 no.3
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    • pp.421-439
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    • 2016
  • Corrosion of embedded reinforcing bars is recognized as being the major cause of deterioration of reinforced concrete structures. With regard to maintenance strategies of concrete nuclear structures, the monitoring of cracking remains of primary importance. Recently, authors have developed a post-treatment technique to extract crack features from continuous computations. In this paper, such technique is applied to carry out a numerical analysis of an accelerated corrosion test. Obtained results allow highlighting specific propagation and failure mechanisms that characterize corrosion-induced cracking.

Ductility of concrete slabs reinforced with low-ductility welded wire fabric and steel fibers

  • Tuladhar, Rabin;Lancini, Benjamin J.
    • Structural Engineering and Mechanics
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    • v.49 no.4
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    • pp.449-461
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    • 2014
  • The use of low-ductility welded wire fabric (WWF) as a main tensile reinforcement in concrete slabs compromises the ductility of concrete structures. Lower ductility in concrete structures can lead to brittle and catastrophic failure of the structures. This paper presents the experimental study carried out on eight simply supported one-way slabs to study the structural behavior of concrete slabs reinforced with low-ductility WWF and steel fibers. The different types of steel fibers used were crimped fiber, hooked-end fiber and twincone fiber. The experimental results show that the ductility behavior of the slab specimens with low-ductility reinforcement was significantly improved with the inclusion of $40kg/m^3$ of twincone fiber. Distribution of cracks was prominent in the slabs with twincone fiber, which also indicates the better distribution of internal forces in these slabs. However, the slab reinforced only with low-ductility reinforcement failed catastrophically with a single minor crack and without appreciable deflection.

Street Optics (거리의 시각)

  • Kenaan, Hagi
    • The Journal of Art Theory & Practice
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    • no.10
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    • pp.25-46
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    • 2010
  • Street art operates within an already given visual order: the visuality of the modern city in which the regimentation of the image has become fully adaptive to-what Fredric Jameson termed-the logic of late capitalism. What is the relationship between street art and the hegemonic forms of the image dictated by the "city's rulers"? Does street art evoke an alternative kind of spectatorship? Can the unsolicited visual intervention in the life of the city open up an "optics" that resists the reifying patterns of the contemporary gaze? This paper follows Baudrillard's pioneering analysis of graffiti, arguing that the visuality of a certain kind of street images carries an important potential of challenging the hegemonic manner in which the contemporary image has come to dominate the field of vision.

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Primary oral soft tissue angiosarcoma of the cheek: a case report and literature review

  • Fomete, Benjamin;Samaila, Modupe;Edaigbini, Sunday;Agbara, Rowlan;Okeke, Uche Albert
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.41 no.5
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    • pp.273-277
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    • 2015
  • Angiosarcoma is a rare and aggressive malignant tumor that has a poor prognosis. It represents less than 1% of all malignancies occurring in the oral cavity and salivary glands. We present a 35-year-old male with angiosarcoma of the cheek following traumatic injury and a review of the current literature.