• Title/Summary/Keyword: 작용식

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A Prediction of Shear Strength Using Arch Models in Reinforced Concrete Beams without Web Reinforcement (아치모델을 이용한 복부보강이 안된 철근 콘크리트 보의 전단강도 산정)

  • 김대중
    • Magazine of the Korea Concrete Institute
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    • v.10 no.6
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    • pp.233-240
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    • 1998
  • A rational expression, developed to predict the shear strength of reinforced concrete beams, is derived from the relationship between shear and the rate of change of bending moment along a beam coupled with experimental findings for the arch action. The proposed ultimate shear strength equation, arising from analytical premises and then calibrated with experimental data, is a similar form to the ACI 318 equation derived mainly from empirical approach. The proposed equation depends on the concrete compressive strength, amount of longitudinal steel content, and the shear span-to-depth ratio, and rationally reflects the shear resistance mechanism of combined beam action and arch action in reinforced concrete beams. The proposed equation applied to existing test data and the results were compared with those predicted by the ACI 318 equation and the Zsutty's equation.

Cellular Immune Response of the Grasshopper, Euprepocnemis shirakii Bolivar Following Injection of Bacillus subtilis (세균(Bacillus subtilis)에 대한 등검은메뚜기(Euprepocnemis shirakii Bolivar)의 세포성 면역반응)

  • 장병수;문명진한성식여성문
    • The Korean Journal of Zoology
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    • v.35 no.3
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    • pp.383-394
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    • 1992
  • 비병원성 세균인 고acirlus subtilis(ATCC6633)를 등검은메뚜기(Euprepocnemis shr'rakii Bolivar)의 성충 복강에 주입한 후, 혈구의 반응양상을 투과전자현미경으로 관찰하였다. 세균에 대한 혈구의 면역반응은 plasmatocyte와 granulocyte에 의한 식 세포작용(phagocytosis)의 형태로 이루어졌으며, 결절형꽁(nodule formation)은 일어나지 않았다. 식 세포작용의 초기 반응은 혈구의 세포질 돌기가 돌출되 면서 이물질을 둘러싼 후, 원형질막과의 융합에 의해 식포가 형성되었고, 식포의 주변부에서는 일차 리소조옴의 집적이 관찰되었으며, 이런 과정은 세균 주입후, 10분 이내에 완료되었다. 일차 리소조옴은 세균 주입 후 1시간 이내에 식포의 한계막과 융합하여 이차 리소조옴을 형성하였으며, 소화된 이물질은 9시간 이내에 exocytosis에 의해 배출 되었다.

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Improvement Effect of Salicornia herbacea L. Diet on the Acne Skin (여드름 피부에 미치는 함초 식이의 피부 개선 효과)

  • Lim, Mi-Ra;Kang, Sang-Mo
    • Journal of the East Asian Society of Dietary Life
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    • v.19 no.5
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    • pp.750-760
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    • 2009
  • In this study, the various effects of Salicornia herbacea, including antioxidative function, antibiotic, and anti-inflammatory effect, and the effect of sebiparous reduction due to intervention of the DHT hormone were investigated using. The result of this study Based on this analysis, the serum total cholesterol, triglyceride, and WBC were found to be significantly decreased and SOD, Ca, K, and Zn were shown to be significantly increased significantly in the group that received the SH pill group after trial fora 12 week trials. Testosterone and DHT were increased in the SH pill group, but it was not statistically significant. In the case of the skin condition measurements, the number of blackhead pores, skin oiliness, keratin and, MIC were significantly decreased, and the pH was decreased to normal pH in the SH pill group. Therefore, it was confirmed that overall skin condition was improved due to Salicornia herbacea diet. The results of this research result can contribute so demonstrate the potential of actively using that the Salicornia herbacea can be actively developed as a health supplement, and a medication.

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Lateral Earth Pressures Acting on Passive Piles (수동(受動)말뚝에 작용(作用)하는 측방토압(側方土壓))

  • Hong, Won Pyo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.4 no.2
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    • pp.77-88
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    • 1984
  • By investigating the characteristics of various factors about soil and pile containing in the theoretical equations of lateral earth pressures acting on a row of passive piles which have been already presented in the previous. papers, the equations are arranged as a simple form which is convenient to use. The simplified equation is examined so as to be also utilized to single passive pile. And a discussion is carried out on the method how to apply the equations to field. As the result of this study, the equations can be arranged as a simple linear equation with the coefficients of lateral force $K_{p1}$ and $K_{p2}$. And the simple linear equation is composed of cohesion c and earth pressures ${\sigma}_H$ acting on backside of pile's row against the direction of soil deformation. In order to apply this equation to field, the active earth pressure can be considered as the earth pressure ${\sigma}_H$. The validity of this consideration is justified by comparing the theoretical values of lateral earth pressures acting on piles with the values observed in field.

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Evaluation on Stiffness of High-strength Mortar-filled Sleeve Bar Splice Under Cyclic Loading (반복하중이 작용하는 고강도 모르타르 충전식 슬리브 철근이음에 대한 강성 평가)

  • Kim, Hyong Kee;Chung, Goo Yong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.17 no.1
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    • pp.85-93
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    • 2013
  • In order to make a more reasonable evaluation on the stiffness of the high-strength mortar-filled sleeve bar splices under cyclic loading, we investigated and analyzed the existing experiment data of 106 full-sized reinforcing bar splices with test variables such as compressive strength of mortar, development length of reinforcement and sleeve type, etc. The following were found: 1) If mortar and the reinforcement development length with $f_{g^*}$(L/d) of more than 340 is used, the cast iron sleeve bar splices for SD350 and SD400 will have the stiffness of higher than A class of the AIJ code. 2) If mortar and the reinforcement development length with $f_{g^*}$(L/d) of more than 400 is used, the cast iron sleeve splices and pipe sleeve splices for SD500 will have the stiffness of higher than A class of the AIJ code.

The Calculation and Design Method of Active Earth Pressure with Type of Gravity Structures (중력식 구조물의 형태에 따른 주동토압 산정과 설계법 제안)

  • Kim, Byung-Il;Jeong, Young-Jin;Kim, Do-Hyung;Lee, Chung-Ho;Han, Sang-Jae
    • Journal of the Korean Geotechnical Society
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    • v.30 no.4
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    • pp.47-63
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    • 2014
  • In this study theories of earth pressure such as Rankine, Coulomb, Trial Wedge, Improved Trial Wedge, used in the design for onshore and offshore structures, are analyzed and the characteristics of loaded pressure to virtual back (wall, plane) and wall surface in accordance with the structure type are suggested. To investigate characteristics of earth pressure, gravity retaining wall with inclined angle and cantilever wall with inclined ground are movilized for onshore structures and caisson and block type quay wall are mobilized for offshore structures. Based on various theories, the earth pressure applied angle(wall friction angle) and sliding angle toward the wall, which is influenced by the heel length, are calculated and compared. In the case of long heel, the pressure by Rankine's method in virtual plane and the mobilized angle are most reasonably estimated by the ground slope, and in the case of short heel, the pressure by Coulomb's method and the mobilized angle by the angle of wall friction. In addition, the sliding angle toward the wall estimated by the improved trial wedge method is large than the value of Rankine's method. Finally, in this study the reasonable method for calculating the pressure and the mobilized angle that can be applied to the routine design of port structures is proposed. The proposed method can decide the earth pressure with length of a heel and a self weight of retaining wall according to sliding angle toward the wall.

The Effects of Flipped Learning Applied to Home Economics Education on Academic Engagement, Self-Directed Learning Ability and Social Interaction of Middle School Students (가정교과에 적용한 거꾸로 수업이 중학생의 수업참여도, 자기주도학습능력 및 사회적 상호작용에 미치는 효과)

  • Cho, Hee-su;Jang, Yoon-Ok
    • Journal of Korean Home Economics Education Association
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    • v.28 no.4
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    • pp.1-20
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    • 2016
  • This study aims to investigate the effects of flipped learning applied to home economics education on improving middle school students' academic engagement, self-directed learning ability and social interaction. The subjects of this study were 129 third-grade students in middle school. To verify the effects of flipped learning adequately, 129 middle school students divided into two groups have participated in the study over a course of nine weeks. One group was taught in the traditional instructed learning method while the other one in the flipped learning methods. The two groups were taught in 13 sessions in total once or twice a week, and each session took 45 minutes. For pretest and post test, the questionnaire consisting of academic engagement scale, self-directed learning scale and social interaction scale were used. To analyze data, ANCOVA was used to examine significant differences between two groups. The main results of this study were the following : First, students who participated in flipped learning are more improved than those who participate in instructed learning in academic engagement. Second, students who joined in flipped learning are much more improved than those who joined in instructed learning in self-directed learning ability. Third, students who join in flipped learning were much more improved than those who joined in instructed learning in social interaction.

심해파랑의 비선형상호작용에 의한 에너지 전달의 계산

  • 오병철;이길성
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1996.10a
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    • pp.119-123
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    • 1996
  • 파랑성분간의 비선형상호작용에 의한 에너지의 교환은 스펙트럼 파랑에너지 보존방정식의 중요한 원천항(source)의 하나이며 이의 정확한 계산에 관한 연구가 파랑모델에서 중요한 문제로서 제기되어 왔다. 그러나 비선형에너지 전달을 엄밀하게 계산하는데는 많은 시간이 소요되기 때문에 현재 현업에서는 스펙트럼파라메타로서 간략화한 식을 사용하고 있다. 비선형상호작용은 파랑이 발달하고 있는 풍역에서 중요하기 때문에 비대칭 스펙트럼에 대한 비선형상호작용의 파라메터화는 풍속이 급변하는 풍장에서 매우 중요하다. (중략)

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The Effect of Cut-slope on Structural Behavior of Cut-and-Cover Tunnel (굴착경사가 개착식터널의 구조적거동에 미치는 영향에 관한 연구)

  • 유건선
    • Journal of the Korean Geotechnical Society
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    • v.17 no.6
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    • pp.245-255
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    • 2001
  • Existing cut-and-cover tunnels are designed regardless of cut-slope under the assumption that the overburden weight of backfill soil acts on tunnel arch and the earth pressure at rest acts on tunnel walls. However, actual earth pressures acting on the tunnel lining depend on open-cut size composed of cut-slope and cut-width, and thus the tunnel lining shows a different structural behavior. This study investigated the effect of cut-slope on structural behavior of the cut-and-cover tunnel lining as follows; Firstly, a comprehensive numerical analysis method using FLAC2D code was used and verified by field measurements of tunnel profile. Secondly, based on the verified numerical analysis technique, earth pressure acting on the lining, and displacement and sectional force developed on the lining were estimated with various shapes of cut-slopes$30^{\circ}\;, 456{\circ},\; 60^{\circ},\; and\;75^{\circ}%). Numerical analysis results indicate that the steeper cut-slope shows the more displacement and moment of the tunnel lining.

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Prediction of SNP interactions in complex diseases with mutual information and boolean algebra (상호정보와 부울대수를 이용한 복합질환의 SNP 상호작용 예측)

  • Leem, Sang-Seob;Wee, Kyu-Bum
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.11
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    • pp.215-224
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    • 2010
  • Most chronic diseases are complex diseases which are caused by interactions of several genes. Studies on finding SNPs and gene-gene interactions involved in the development of complex diseases can contribute to prevention and treatment of the diseases. Previous studies mostly concentrate on finding only the set of SNPs involved. In this study we suggest a way to see how these SNPs interact using boolean expressions. The proposed method consists of two stages. In the first stage we find the set of SNPs involved in the development of diseases using mutual information based on entropy. In the second stage we find the highest accuracy boolean expression that consists of the SNP set obtained in the first stage. We experimented with clinical data to demonstrate the effectiveness of the proposed method. We also compared the differences between our method and the previous results on the SNP associations studies.