• Title/Summary/Keyword: O'Neill

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REFLECTIONS OF COMPLETELY REGULAR AND ZERO-DIMENSIONAL QUASI-ORDERED SPACES

  • Shin, Seon-Ho
    • The Pure and Applied Mathematics
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    • v.10 no.1
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    • pp.25-35
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    • 2003
  • We study equivalent definitions and some categorical properties of completely regular quasi-ordered spaces and zero-dimensional quasi-ordered spaces. Using the o-completely regular (resp. o-zero-dimensional) filters on a completely regular (resp. zero-dimensional) quasi-ordered space, we show that the category COMPOS (resp. ZCOMPOS) of compact (resp. compact zero-dimensional) partially ordered spaces is reflective in the category CRQOS (resp. ZQOS) of completely regular (resp. zero-dimensional) quasi-ordered spaces and continuous isotones.

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Computation of Plug Capacity for Open -Ended Piles Driven into Sands (모래지반에 타입된 개단말뚝의 관내토지지력 산정)

  • 백규호;이승래
    • Geotechnical Engineering
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    • v.9 no.4
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    • pp.7-16
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    • 1993
  • Calibration chamber tests were conducted on open -ended model piles driven into dried siliceous sands with different soil conditions in order to clarify the effect of soil conditions on plug capacity, The model pile used in the test series was devised so that the bearing capacity of an open -ended pile could be measured out into three components , outside shaft resistance. plug resistance and tip resistance. Under several assumption, the value of earth pressure coefficient in the soil plug is calculated. It is gradually reduced with increase in the longitudinal distance from the pile tip. At the bottom of soil plug, it tends to decrease with increase in the penetration depth and relative density, and to increase with the increase of ambient pressure. In comparison of measured and calculated plug capacities using the one -dimensional analysis, we note that API code and one -dimensional analysis combined with P suggested by Randolph et al. and O'Neill et al. result in great underestimation of the plug capacity. Therefore, based on the test results, an empirical equation was suggested to compute the earth pressured coefficient to be used in the calculation of plug capacity using the one -dimensional analysis. and it produces proper plug capacities for all soil conditions.

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Numerical Study on Feeding Efficiency in Sand Dollar Aggregation (연잎성게의 군집 형태에 따른 포식 효율의 수치적 연구)

  • O, Gwang-Seok;Kim, Jong-Am
    • Proceeding of EDISON Challenge
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    • 2013.04a
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    • pp.310-315
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    • 2013
  • 연잎성게가 몸체의 방향을 유입류에 평행하게 맞추어 포식하는 이유에 대해서는 크게 유체역학적인 설명과 생태학적인 설명이 양립하고 있다. O'Neill과 Nakamura와 같은 연구자들에 의해 연잎성게의 이러한 행태를 유체역학의 관점에서 설명할 수 있지만, 정작 셋 이상의 연잎성게 군집의 포식 효율에 대해서는 개체 수에 기반을 둔 생태학적 관점에 의존하고 있다. 따라서 본 연구에서는 연잎성게 군집 내에서의 개체들의 배열을 모델링하고, 다양한 군집 배열에서 개체들의 포식 효율을 EDISON_전산열유체 시스템을 활용해 분석하였다. 특히 포식 효율을 결정하는 과정에서 얇은 익형 이론을 이용함으로써 포식효율을 결정하는 유체역학적 특성이 양력계수임을 확인하였다.

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Multicarbohydrase Enzymes for Non-ruminants

  • Masey O'Neill, H.V.;Smith, J.A.;Bedford, M.R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.2
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    • pp.290-301
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    • 2014
  • The first purpose of this review is to outline some of the background information necessary to understand the mechanisms of action of fibre-degrading enzymes in non-ruminants. Secondly, the well-known and understood mechanisms are described, i) eliminating the nutrient encapsulating effect of the cell wall and ii) ameliorating viscosity problems associated with certain Non Starch Polysaccharides, particularly arabinoxylans and ${\beta}$-glucans. A third, indirect mechanism is then discussed: the activity of such enzymes in producing prebiotic oligosaccharides and promoting beneficial cecal fermentation. The literature contains a wealth of information on various non starch polysaccharide degrading enzyme (NSPase) preparations and this review aims to conclude by discussing this body of work, with reference to the above mechanisms. It is suggested that the way in which multi- versus single-component products are compared is often flawed and that some continuity should be employed in methods and terminology.

The function of language and its limitations in the Modern theater (현대 연극에 나타난 언어의 위기 및 그 한계)

  • Yang, Gi-Chan
    • Lingua Humanitatis
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    • v.8
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    • pp.79-93
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    • 2006
  • The modern play is going through a change that is differentiating it from the plays of yesterday. The importance of narration through language, specifically that of words spoken on stage as a means of communication is being replaced by images and minimalism of words. The narration that depended on spoken words today depends more on the images that are conjured on stage. This movement shows also the very development of stage and its craft in the domain of theater and especially holds true in the avant-garde theaters of today. The avant-garde theater, in trying to duplicate the reality does not confine itself to oratory rhetorics that we see in the traditional plays of the past but expresses itself by mimicking the reality to the utmost possible.

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Effect of tornadoes on residential masonry structures

  • Pinelli, J.P.;O'Neill, S.
    • Wind and Structures
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    • v.3 no.1
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    • pp.23-40
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    • 2000
  • In the early morning hours of February 23rd, 1998, seven large tornadoes ravaged central Florida. A total of 42 people were killed and millions of dollars of damage was done. A strip mall and other commercial structures sustained considerable damage and several residential areas were completely destroyed. Based on field observations, the paper examines the causes and sequence of structural failure for the masonry single family homes. Wind speeds are estimated based on the observed damage, and compared to the meteorological data. Finally, recommendations are given that could help to eliminate or reduce similar failures in the future. It was found that with simple, cost effective measures, most if not all of the damage could have been prevented.

Increased Poly(3-Hydroxybutyrate) Accumulation in Recombinant Escherichia coli from Whey by Agitation Speed Control

  • Kim, Beom-Soo;Brian K. O'Neill;Lee, Sang-Yup
    • Journal of Microbiology and Biotechnology
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    • v.10 no.5
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    • pp.628-631
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    • 2000
  • The timing of poly(3-Hydroxybutyrate) (PHB) biosynthesis was controlled by varying the agitation speed of a stirred tank fermentor during the pH-stat fed-batch culture of recombinant Escherichia coli strain GCSC 6576 harboring pSYL107. Using a concentrated whey solution containing ca. 200 g/l lactose as the nutrient feed, the PHB content was only 57% after 35h due to volumetric limitation of the fermentor. However, by limiting the oxygen by maintaining the agitation speed at 300 rpm, the final PHB content increased to 70% after 70h with a cell concentration of 15 g/l. When the agitation speed was increased up to 500 rpm, a cell concentration of 31 g/l with 80% PHB was obtained after 52h. A further increase in the maximum agitation speed increased the cell concentration, PHB concentration, and PHB productivity, however, the PHB content decreased to 56-58%.

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A Case Study on the Design of Drilled Shaft on Soft Ground in Vietnam (베트남 연약지반에서의 현장타설말뚝 설계 사례)

  • Seo, Won-Seok;Cho, Sung-Han;Choi, Ki-Byung
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.591-604
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    • 2008
  • In this study, two design examples of drilled shafts on soft ground in Ho-Chi-Minh City, Vietnam are introduced. One is for a 27-story apartment and the other is for a Arch bridge over Saigon river. Unlikely the normal cases in Korea, all of the bored pile foundations are supposed to be placed on soil layers. Therefore, skin friction between pile and ground is the most crucial design parameter. Three methods using SPT N value of sandy soil -Korean Road Bridge Code(1996), Reese and Wright (1977), and O'Neill and Reese (1988)- were adopted to obtain an ultimate axial bearing capacity. In order to verify the calculated bearing capacity, 3 sets of static load test and a Osterberg Cell test were performed at an apartment site and a bridge site respectively. LRFD (Load Resistance Factored Design) method was compared with ASD (Allowable Stress Design) method. On application of ASD method, safety factor for skin friction was adopted as 2 or 3 while safety factor for end bearing was 3. The design bearing capacities from ASD method matched well with those from LRFD method when safety factor for skin friction was adopted as 2.

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Case Study on Design of Axially Loaded Drilled Shafts in Intermediate Geomaterials(II) (IGM에 근입된 현장타설말뚝의 설계사례 연구(II))

  • Lee, Jung-Hoon;Kim, Won-Cheul;Seo, Deok-Dong;Nam, Hyun-Woo
    • Journal of the Korean GEO-environmental Society
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    • v.7 no.1
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    • pp.19-28
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    • 2006
  • In Korea, none of the design methods, which can consider the properties of hard soil, weathered rock and the condition of construction, are suggested. Therefore, the properties of geomaterial are simply classified into three categories such as sand, clay and rock for the resistance estimation of axially loaded drilled shafts in Korea. However, in America, O'Neill et al.(1996) presented design methods for a new category of geomaterial which is between soil and rock termed "intermediate geomaterials, IGM's". And FHWA(1999) adapted above most complete classification of geomaterials in its design manual. However, in Korea, these properties are depended on the engineer's judgement, the weathered rocks may be counted as soils, although they may be referred to as IGM's in America. In this study, the applicability of IGM method was investigated through the three construction sites in Korea. For the comparison, two geomaterial properties are applied, respectively. The one was sound soil condition and the other was IGM condition and classical design method and IGM method were applied, respectively. The results showed that the predicted bearing capacities of drilled shafts with IGM's were larger than the predicted values by the classical design method with sound soil condition.

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Evaluation of p-y Curves of Piles in Soft Deposits by 3-Dimensional Numerical Analysis (3차원 수치해석을 이용한 점성토 지반의 p-y 곡선 산정)

  • Lee, Si-Hoon;Kim, Sung-Ryul;Lee, Ju-Hyung;Chung, Moon-Kyung
    • Journal of the Korean Geotechnical Society
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    • v.27 no.7
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    • pp.47-57
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    • 2011
  • The p-y curve has been used to design pile foundations subjected to lateral loading. Although the p-y curve has a large influence on the pile lateral behavior, p-y curves have not been clearly suggested. In this study, the p-y curve of clay was evaluated for drilled shafts in marine deposits by using 3-dimensional numerical analyses. First, the optimization study was performed to properly determine boundary extent, mesh size, and interface stiffness. The numerical modeling in the study was verified by comparing the calculated and the pile loading test results. Then, the p-y curves of single and group piles were evaluated from the parametric study. The selected parameters were pile diameter, pile Young's modulus and pile head fixed condition for a single pile, and pile spacing for group piles. Finally, the p-multiplier was evaluated by comparing the p-y curves of a single pile and group piles. As a result, the p-multiplier at pile spacing of 3D was 0.83, 0.67 and 0.78 for the front, middle, and back row piles, respectively, and showed values similar to those of O'Neill and Reese (1999). For the pile group with pile spacing larger than 60, the group effect can be ignorable.