• Title/Summary/Keyword: 비 보존력

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Geometric Non-linear Analysis of Plane Frame Structures subjected to Conservative and Non-conservative Forces (보존력(保存力) 및 비보존력(非保存力)을 받는 평면(平面)뼈대 구조물(構造物)의 기하적(幾何的) 비선형(非線形) 해석(解析))

  • Kim, Moon Young;Chang, Sung Pil
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.10 no.1
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    • pp.17-26
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    • 1990
  • A solution strategy for geometric non-linear analysis for the plane frame structures subjected to conservative and non-conservative forces is presented. By making efficient combination of the load incremental method and the displacement incremental method, this strategy can find postbuckling configuration such as snap-through and turning-back phenomena which cannot be easily found by the conventional load and displacement incrementation scheme. In the case of the analysis of the framed structure subjected to circulatory non-conservative forces, the total tangent stiffness matrix becomes unsymmetric and when calculating the incremental load and unbalanced load vector components, the direction change of the non-conservative forces is considered. Several example problems to demonstrate the feasibility of the present strategy, over ranges of deformation that are well beyond those likly to occur in practical framed structures, are given and discussed.

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Investigation of Harmful Microorganisms and Physiological Characteristics of Mycelia in the Bed-log of Shiitake Strains Showing Low Fruit-body Productivity (버섯 발생이 부진한 표고골목 내부균사의 생리적 특성 및 해균 조사)

  • Bak, Won-Chull;Lee, Bong-Hun;Ryu, Sung-Ryul;Ka, Kang-Hyeon
    • The Korean Journal of Mycology
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    • v.34 no.2
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    • pp.88-91
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    • 2006
  • Attempts were made to investigate the conditions of mycelia of one low-temperature type strain and one high-temperature type strain of shiitake showing poor fruit-body formation in bed-log, and to survey harmful microorganisms formed on the log surface in Gapyung County, Korea. When tested the growing ability of mycelia, the low-temperature type strain showed ca. 1.1% decrease compared with preserved original strain. And, the high-temperature type one showed ca. 8.0% decrease. The growth of isolated mycelia was tested in sawdust medium. The high-temperature type strain showed ca. 10.8% decrease compared with original strain, and the low-temperature type one showed ca. 25.1% decrease. Weight reduction rate was investigated. The high-temperature strain showed ca. 20.1% decrease and the low-temperature one ca. 19.0%. When compared with non-treatment, original high-temperature type strain showed 107.0% decrease, the isolated high-temperature type strain 49.5%, original low-temperature type one 85.4%, isolated low-temperature type one 50.0%. As the results of confrontation culture, the high-temperature type strain and the low-temperature type one were same as the original ones, respectively. And, in the bed-logs, Hypoxylon truncatum, Coriolus versicolor, Inonotus xeranticus, Daedaleopsis tricolor, Graphostroma platystoma, two species of Myxomycetes, Trichoderma sp. Hypoxylon fragiforme, H. howeianum, and Nitschkia confertula were observed as harmful microorganisms, and the bed-logs were not in good condition.

The Energy Conserving Algorithm of the System Acted by an Exponential Impact Force (지수형 충격력을 받는 시스템의 에너지보존 알고리듬)

  • 윤성호
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.16 no.3
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    • pp.311-319
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    • 2003
  • This paper aims at investigating the exact dynamic response of the system undergoing a exponential impact force from the viewpoints of conservations of momentum and energy. The midpoint method applied in the Newmark's family algorithm is found to be identical to the case of the application of the trapezoidal method which provides conservations of momentum and energy. For the linear impact force the mid point, the trapezoidal and the (n+1) point method exactly meet the conservation characteristics independent of the size of integration interval. On the other hand, constants for the dynamic motion resulting from the nonlinear impact are underestimated or overestimated by these method mentioned above. To overcome this indispensible error, the Simpson 1/3 method as one of multi step methods whose advantages is to use longer time interval with the same number of evaluation functions is adopted for the exact conservations of momentum and energy. Moreover, the suggested method is expected to expand the similar algorithm for the general dynamic motion including finite rotations.

Automatic Load and Displacement Incremental Algorithm for Geometric Non-Linear Finite Element Analysis of the Structure subjected to Conservative and Non-conservative Forces (보존력(保存力) 및 비보존력(非保存力)을 받는 구조물(構造物)의 기하적(幾何的) 비선형(非線形) 유한요소해석(有限要素解析)을 위한 하중(荷重) 및 변위증분(變位增分) 알고리즘의 개발(開發))

  • Kim, Moon Young;Chang, Sung Pil
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.10 no.2
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    • pp.11-22
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    • 1990
  • An automatic incremental algorithm for geometric non-linear finite element analysis of the structures subjected to the conservative and non-conservative forces is presented. By making efficient combination of the load incremental method and the displacement incremental method, this scheme can trace various post-buckling equilibrium path such as snap-through and turning-back. Several numerical examples to demonstrate the feasibility of the present algorithm, over ranges of deformation that are well beyond those likely to occur in practical structures, are given and discussed.

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The Dynamic Post-Buckling Analysis of the Non-Conservative System including Damping Effects (감쇠효과(減衰效果)를 고려한 비보존력계(非保存力系)의 동적(動的) 후좌굴(後挫屈) 해석(解析))

  • Kim, Moon Young;Chang, Sung Pil
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.10 no.3
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    • pp.67-75
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    • 1990
  • A geometrically nonlinear analysis procedure including the damping effects is presented for the investigation of the dynamic post-divergence and post-flutter behavior of a non-conservative system. The dynamic nonlinear analysis of plane frame structure subjected to conservative and non-conservative forces is carried out by solving the equations of motion using Newmark method. Numerical results are presented to demonstrate the effects of the internal and external damping forces in the conservative and non-conservative systems.

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In Vitro Assessment on Viability of Human Periodontal Ligament Cells after Storage in Chlorophyllin-added Medium (클로로필린이 첨가된 탈구치아 보존액에서의 치주인대 세포 생활력에 대한 연구)

  • Chung, Won-Gyun;Kim, Jin;Lee, Eun-Ju;Lee, Seung-Jong
    • Restorative Dentistry and Endodontics
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    • v.27 no.6
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    • pp.600-611
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    • 2002
  • 본 연구의 목적은 클로로필린이 치주인대 세포 생활력에 미치는 영향을 평가하는데 있다. 치주인대 세포는 건강한 사람에서 발치한 소구치의 치주인대 조직으로부터 채취하여 배양하였다. 비교 기준을 설정하기 위하여, HBSS 내에서 $37^{\ circ}C$로 보관한 치주인대 세포수의 50%가 생존하는데 소요되는 시간을 MTT 분석법에 의해 측정하였다. 그 결과는 6시간이었다. HBSS에 클로로필린 10, 100, 500 nM이 각각 첨가된 3군의 실험 보존액과 F-medium, ViaSpan, Likorol 등 모두 6군의 실험 보존액을 96-well plate에 접종한 후, 치주인대 세포를 동일한 수로 분주하였다. 이를 6시간동안 보관한 후, 각 실험군 보존액에서의 세포 생활력을 MTT 분석법으로 측정하였다 또한, HBSS와 F-medium 및 클로로필린 500 nM이 첨가된 HBSS군의 세포들에 대해 유식세포 계측을 시행하여 각각의 세포주기를 분석하였다. 실험 결과, 클로로필린 500 nM이 첨가된 HBSS에서 보관한 세포들이 가장 높은 생활력을 나타내었으며, 클로로필린이 첨가되지 않은 HBSS에 비해서 유의하게 양호한 세포 생활력 유지 능력을 보였다. 클로로필린으로 처치한 세포들은 클로로필린의 농도가 커짐에 따라 세포 생활력이 증가하는 양상을 나타내었다. 유식세포 계측 결과, HBSS와 F-medium 및 클로로필린 500 nM이 첨가된 HBSS에서 보관한 세포의 77~80%가 G0-G1 단계의 세포 주기로 측정되어, 대부분의 세포들이 안정된 세포 대사 상태를 보이는 것으로 나타났다. 결론적으로, 클로로필린 처치는 치주인대 세포의 생활력 유지에 도움이 되는 것으로 사료된다.

Forgetting based File Cache Management Scheme for Non-Volatile Memory (데이터 망각을 활용한 비휘발성 메모리 기반 파일 캐시 관리 기법)

  • Kang, Dongwoo;Choi, Jongmoo
    • Journal of KIISE
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    • v.42 no.8
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    • pp.972-978
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    • 2015
  • Non-volatile memory (NVM) supports both byte addressability and non-volatility. These characteristics make it feasible for NVM to be employed at any layer of the memory hierarchy such as cache, memory and disk. An interesting characteristic of NVM is that, even though it supports non-volatility, its retention capability is limited. Furthermore NVM has tradeoff between its retention capability and write latency. In this paper, we propose a novel NVM-based file cache management scheme that makes use of the limited retention capability to improve the cache performance. Experimental results with real-workloads show that our scheme can reduce access latency by up to 31% (24.4% average) compared with the conventional LRU based cache management scheme.

Attention-based Unsupervised Style Transfer by Noising Input Sentences (입력 문장 Noising과 Attention 기반 비교사 한국어 문체 변환)

  • Noh, Hyungjong;Lee, Yeonsoo
    • Annual Conference on Human and Language Technology
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    • 2018.10a
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    • pp.434-439
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    • 2018
  • 문체 변환 시스템을 학습하는 데 있어서 가장 큰 어려움 중 하나는 병렬 말뭉치가 부족하다는 것이다. 최근 대량의 비병렬 말뭉치만으로 문체 변환 문제를 해결하려는 많은 연구들이 발표되었지만, 아직까지도 원 문장의 정보 보존(Content preservation)과 문체 변환(Style transfer) 모두를 이루는 것이 쉽지 않은 상태이다. 특히 비교사 학습의 특성상 문체 변환과 동시에 정보를 보존하는 것이 매우 어렵다. Attention 기반의 Seq2seq 네트워크를 이용할 경우에는 과도하게 원문의 정보가 보존되어 문체 변환 능력이 떨어지기도 한다. 그리고 OOV(Out-Of-Vocabulary) 문제 또한 존재한다. 본 논문에서는 Attention 기반의 Seq2seq 네트워크를 이용하여 어절 단위의 정보 보존력을 최대한 높이면서도, 입력 문장에 효과적으로 Noise를 넣어 문체 변환 성능을 저해하는 과도한 정보 보존 현상을 막고 문체의 특성을 나타내는 어절들이 잘 변환되도록 할 뿐 아니라 OOV 문제도 줄일 수 있는 방법을 제안한다. 우리는 비교 실험을 통해 본 논문에서 제안한 방법들이 한국어 문장뿐 아니라 영어 문장에 대해서도 state-of-the-art 시스템들에 비해 향상된 성능을 보여준다는 사실을 확인하였다.

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Antimicrobial Activity of Pectin hydrolysate and its Preservative Effect (펙틴분해물의 항균특성과 식품보존효과)

  • 박미연;최승태;장동석
    • Journal of Food Hygiene and Safety
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    • v.13 no.2
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    • pp.99-105
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    • 1998
  • Pectin hydrolysate prepared from citrus pectin by enzymatic hydrolysis has antimicrobial activity. The antimicrobial activity was increased by its hydrolyzing rate and it was rapidly increased after 70% hydrolysis of the pectin. The antibacterial activity of pectin hydrolysate against Escherichia coli ATCC 11229 was the strongest at pH 4.9~5.5, but it diminished slightly at neutral pH values. The antibacterial activity of pectin hydrolysate was stronger than those of against molds and yeasts. The growth of bacteria submitted to this test except lactics was completely inhibited for 48 hrs at $35^{\circ}C$ by adding 2.0~3.0% pectin hydrolysate. While the growth of Lactococcus lactis ATCC 19435 and Lactobacillus bulgaricus and Penicillium funiculosum ATCC 11797 were reached about 60~70% compared with those of the controls in the same condition. But there was no significant effect on the growth of the yeasts. The antibacterial effect of pectin hydrolysate was significantly stimulated by addition of glycine, ethanol, sodium ascorbate, sodium chloride and sodium acetate. The shelf life of Kimchi containing 1.0% pectin hydrolysate was prolonged above 15 days at $4^{\circ}C$ than that of its control. In case of whitish bean jam viable cell counts were inhibited about 2 log cycles by 10 days at $25^{\circ}C$. According to these results, author can sincerely suggest that pectin hydrolysate will be used as a natural food preservative for inhibition of common bacterial growth without inhibition of lactics and yeasts.

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Mycelial viability and cultivation characteristics of Hypsizygus marmoreus after long-term storage in different conditions (장기 저장 후 느티만가닥버섯(Hypsizygus marmoreus) 균주의 균사 생존력과 재배 특성에 대한 연구)

  • Lee, Hyae-Jung;Ro, Hyeon-Su;Kim, Jong-Guk;Lee, Chang-Yun
    • Journal of Mushroom
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    • v.12 no.1
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    • pp.29-34
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    • 2014
  • Mycelial viability and cultivation characteristics of strains of Hypsizygus marmoreus after long-term storage were investigated. The experimental conditions were the storage at $4^{\circ}C$ using a slant culture technique with or without mineral oil, and in liquid nitrogen tank in the presence of 10% glycerol or 10% glycerol with 5% trehalose. The myceila of four strains of H. marmoreus were thawed at 9, 21, 33, and 45 months after beginning of the storage, and then the growth of the mycelia was measured on a PDA plate with serial transfers to new plate for the recovery. The mycelial growth data after 45 months showed that the mycelia were mostly viable but not fully active particularly when they were stored in liquid nitrogen with 10% glycerol. The growth activity could be fully recovered after second transfer to new PDA plate. Cultivation of mushroom fruiting body using the recovered mycelia also demonstrated that the storage methods employed in this work were applicable for the long-term storage of H. marmoreus.