• Title/Summary/Keyword: Dilation

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Centrifuge modelling of pile-soil interaction in liquefiable slopes

  • Haigh, Stuart K.;Gopal Madabhushi, S.P.
    • Geomechanics and Engineering
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    • v.3 no.1
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    • pp.1-16
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    • 2011
  • Piles passing through sloping liquefiable deposits are prone to lateral loading if these deposits liquefy and flow during earthquakes. These lateral loads caused by the relative soil-pile movement will induce bending in the piles and may result in failure of the piles or excessive pile-head displacement. Whilst the weak nature of the flowing liquefied soil would suggest that only small loads would be exerted on the piles, it is known from case histories that piles do fail owing to the influence of laterally spreading soils. It will be shown, based on dynamic centrifuge test data, that dilatant behaviour of soil close to the pile is the major cause of these considerable transient lateral loads which are transferred to the pile. This paper reports the results of geotechnical centrifuge tests in which models of gently sloping liquefiable sand with pile foundations passing through them were subjected to earthquake excitation. The soil close to the pile was instrumented with pore-pressure transducers and contact stress cells in order to monitor the interaction between soil and pile and to track the soil stress state both upslope and downslope of the pile. The presence of instrumentation measuring pore-pressure and lateral stress close to the pile in the research described in this paper gives the opportunity to better study the soil stress state close to the pile and to compare the loads measured as being applied to the piles by the laterally spreading soils with those suggested by the JRA design code. This test data shows that lateral stresses much greater than one might expect from calculations based on the residual strength of liquefied soil may be applied to piles in flowing liquefied slopes owing to the dilative behaviour of the liquefied soil. It is shown at least for the particular geometry studied that the current JRA design code can be un-conservative by a factor of three for these dilation-affected transient lateral loads.

(Automatic detection of pulmonary nodules in X-ray chest images) (흉부 X선 영상에서의 폐 노쥴 자동 탐지 기법)

  • Sung, Won;Kim, Eui-Jung;Park, Jong-Won
    • Journal of the Korea Computer Industry Society
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    • v.3 no.9
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    • pp.1279-1286
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    • 2002
  • Generally, radiologists can fail to detect pulmonary nodules in up to 30%. If an automatic system can inform the radiologists of thelocations of the doubtful nodules in the X-ray chest images, the frequency of mistakenly observed numbers of the nodules can be potentially reduced. This software is using morphological filtering and two feature-extraction techniques. The morphological filtering is the first process, which subsequently adds the operations of erosion and dilation to the original images so that this process can transform the original X-ray chest images into manageable ones. The false-positives are frequently being mistaken as nodules but actually these are not real nodules. The second process is the two feature-extraction techniques which are used to reduce the false-positives. Therefore, this system will make more effective detection of pulmonary nodules by reducing the false-positives when applied to the X-ray chest images which is difficult to get accurate detection.

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Embedding Mechanism between Pancake and Star, Macro-star Graph (팬케익 그래프와 스타(Star) 그래프, 매크로-스타(Macro-star) 그래프간의 임베딩 방법)

  • 최은복;이형옥
    • Journal of Korea Multimedia Society
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    • v.6 no.3
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    • pp.556-564
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    • 2003
  • A Star and Pancake graph also have such a good property of a hypercube and have a low network cost than the hypercube. A Macro-star graph which has the star graph as a basic module has the node symmetry, the maximum fault tolerance, and the hierarchical decomposition property. And, it is an interconnection network which improves the network cost against the Star graph. In this paper, we propose a method to embed between Star graph, Pancake graph, and Macro-star graph using the edge definition of graphs. We prove that the Star graph $S_n$ can be embedded into Pancake graph $P_n$ with dilation 4, and Macro-star graph MS(2,n) can be embedded into Pancake graph $P_{2n+1}$ with dilation 4. Also, we have a result that the embedding cost, a Pancake graph can be embedded into Star and Macro-star graph, is O(n).

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Radiographic Uterine Diameter Evaluation for the Detection of Uterine Disease in Dogs: A Retrospective Study

  • Yun, Sookyung;Lee, Jeosoon;Choi, Mincheol;Yoon, Junghee
    • Journal of Veterinary Clinics
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    • v.34 no.6
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    • pp.420-424
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    • 2017
  • Cystic endometrial hyperplasia (CEH) and uterine dilation (hydro-, muco-, hemato- and pyometra) are common uterine diseases in intact female dogs. The aim of the present study was to assess the usefulness of digital abdominal radiography in diagnosing uterine disease in intact female dogs. Two hundred and thirteen intact female dogs were included, and were classified into four groups on the basis of radiographic uterine visibility (visible/invisible) and ultrasonographic findings (normal uterus/abnormal uterine condition including CEH and uterine dilation). For each dog, the ratio of the maximum uterine diameter to the height of the fifth lumbar vertebral body (U/L5 ratio) was calculated on radiographs. There were 78 and 135 dogs in the normal and abnormal groups, respectively; 34.6% normal and 53.5% abnormal uteri were visible on abdominal radiographs. Our results suggested that a mean U/L5 ratio of $1.18{\pm}0.53$ ($mean{\pm}2SD$) indicated a normal radiographic uterus diameter, and that a value of > 1.60 should be used as an indicator of uterine disease in clinical practice. However, because false negative results were noted, radiography cannot replace ultrasonography for assessment of the uterus.

A New Embedding of Pyramids into Regular 2-Dimensional Meshes (피라미드의 정방형 2-차원 메쉬로의 새로운 임베딩)

  • 장정환
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.2
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    • pp.257-263
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    • 2002
  • A graph embedding problem has been studied for applications of resource allocation and mapping the underlying data structure of a parallel algorithm into the interconnection architecture of massively parallel processing systems. In this paper, we consider the embedding problem of the pyramid into the regular 2-dimensional mesh interconnection network topology. We propose a new embedding function which can embed the pyramid of height N into 2$^{N}$ x2$^{N}$ 2-dimensional mesh with dilation max{2$^{N1}$-2. [3.2$^{N4}$+1)/2, 2$^{N3}$+2. [3.2$^{N4}$+1)/2]}. This means an improvement in the dilation measure from 2$^{N}$ $^1$in the previous result into about (5/8) . 2$^{N1}$ under the same condition.condition.

Facial Image Recognition Based on Wavelet Transform and Neural Networks (웨이브렛 변환과 신경망 기반 얼굴 인식)

  • 임춘환;이상훈;편석범
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.37 no.3
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    • pp.104-113
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    • 2000
  • In this study, we propose facial image recognition based on wavelet transform and neural network. This algorithm is proposed by following processes. First, two gray level images is captured in constant illumination and, after removing input image noise using a gaussian filter, differential image is obtained between background and face input image, and this image has a process of erosion and dilation. Second, a mask is made from dilation image and background and facial image is divided by projecting the mask into face input image Then, characteristic area of square shape that consists of eyes, a nose, a mouth, eyebrows and cheeks is detected by searching the edge of divided face image. Finally, after characteristic vectors are extracted from performing discrete wavelet transform(DWT) of this characteristic area and is normalized, normalized vectors become neural network input vectors. And recognition processing is performed based on neural network learning. Simulation results show recognition rate of 100 % about learned image and 92% about unlearned image.

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A Comparison of Barton-Bandis Joint Model and Mohr-Coulomb Joint Model for Tunnel Stability Analysis with DEM (개별요소법을 이용한 터널 안정성 해석에 있어 Barton-Bandis 절리 모델과 Mohr-Coulomb절리 모델의 비교)

  • 이성규;김치환
    • Tunnel and Underground Space
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    • v.11 no.2
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    • pp.167-173
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    • 2001
  • The joint model has influence on the results of discontinuum analysis. In this study the results of discontinuum analysis with Barton-Bandis joint model(BB model) and with Mohr-Coulomb joint model(MC model) are compared. The results of continuum analysis under the same condition are compared with the results of discontinuum analysis to investigate the behavior of rockmass around tunnel. The result of continuum analysis and that of discontinuum analysis with BB model show similar distribution of displacement and stress. On the other hand, the discontinuum analysis with MC model shows different displacement distribution and stress distribution. Moreover, the displacement and minor principal stress of the discontinuum analysis with MC model are smaller than those of continuum analysis, although the joints are explicitly considered in the discontinuum analysis. These results are originated from the limitation of MC model in simulating joint deformation behavior, especially the assumption of constant dilation jingle independent of it)int 7hear displacement.

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Analysis of Diameter Effects on Skin Friction of Drilled Shafts in Sand (사질토 지반에 설치된 현장타설말뚝의 말뚝지름에 따른 주면마찰력 분석)

  • Lee, Sung-June
    • Journal of the Korean Geotechnical Society
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    • v.29 no.1
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    • pp.161-170
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    • 2013
  • In this paper, numerical pile segment analysis is conducted with an advanced soil elastoplastic model to investigate the diameter effects on skin friction behaviour of a drilled shaft in sand. Ultimate skin friction and 't-z' behavior from the pile segment analyses for drilled shafts show good agreement with those from design methods. Higher ultimate skin friction for the smaller diameter pile is related to the greater increase in the effective radial stress at the interface due to the localized dilation at and near the pile interface. Stiffer t-z curve for the smaller diameter pile is related to the early occurrence of three shear stages (early, dilation, constant volume shear stages). The diameter effects on ultimate skin friction of drilled shafts are more prominent for denser sand and lower confining pressure.

Immunocytochemical Investigation on the Intracisternal Accumulations of Storage Protein in Pea Cotyledon Cells (완두 자엽세포의 소포체 내강에 축적된 저장 단백질에 대한 면역세포화학적 연구)

  • Jeong, Byung-Kap;Park, Hong-Duok
    • Applied Microscopy
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    • v.31 no.2
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    • pp.199-206
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    • 2001
  • In 1980s, the fragmentation or subdivision of protein deposits at the periphery of protein storage vacuole was suggested as the only route of PB development in pea cotyledon cells. Since then, other independant processes such as terminal dilation , transformation and de novo development have been discussed as alternative routes for PB development, and today, these multiple mechanisms of PB development are accepted as a result of active investigations. For analysis of the protein accumulations in the ER cisternae during seed development, immunocytochemical gold labellings were applyed on the single cells separated by enzymatic digestion from cotyledon tissue. Anti-legumin labellings at the early stage, and anti-vicilin labellings at the intermediate stage were observed on the protein-filled ER. The $\alpha-Tip$, which is the ER retention protein, was labelled somewhat at late stage, and PPase, a sort of tonoplast membrane protein, was labelled at early stage.

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Effects of Sagungsan on the Hemostasis, Intracranial Pressure, Blood Pressure and Cardiovascular System in Expreimental Animals (사궁산(莎芎散)이 실험동물(實驗動物)의 지혈(止血), 뇌압(腦壓), 혈압(血壓) 및 심혈관계(心血管系)에 미치는 영향(影響))

  • An, Il-Hoe;Park, Young-Soon;Kim, Seh-Gil
    • The Journal of Internal Korean Medicine
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    • v.15 no.1
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    • pp.80-98
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    • 1994
  • According to the original documents, Sagungsan is considered as an effective drug for controlling the hypertensive epistaxis induced by tension of autonomic nerve and it's hyperfunction. The present experiment was designed to understand the effect of Sagungsan extract on the hemostatic action, intracranial pressure, blood pressure and cardiovascular system in experimental animals. And thus the bleeding time, prothrombin time, capillary dilation, blood pressure, Intracranial pressure, and enzymatic analysis of the ATPase activities were studied. The result obtained here were as followings: 1. Sagungsan water extract reduced the bleeding time in mouse, and prolonged the prothrombin time in rabbits. 2. The drug extract increased the tail volume by capillary dilation in rats. 3. The drug extract inhibited the increase of intracranial pressure and arterial blood pressure in rabbits. 4. At the early time, the increase of arterial blood pressure by the drug extract significantly inhibited by pretreated atropin and regitine in rabbits. 5. The drug extract relaxed the smooth muscle by stimulating the Mg2+-Ca2+-ATPase activities of gastric sarcoplasmic reticulum isolated from rabbit stomach. 6. The drug extract stimulated the heart contraction by inhibiting the $Mg^{2+}-Ca^{2+}-ATPase$ activities of cardiac sarcoplasmic reticulum isolated from rabbit heart. The inhibitory mechanism was reversible and noncompatitive. 7. The drug extract increased the hepatic blood volume by stimulating the hepatic total ATPase activities and hepatic metabolism. 8. The drug extract acted as a tranquilizer by inhibiting the neural Na+-K+-ATPase activity. According to the results, Sagungsan water extract dilated the capillaries, stimulated the heart beat, and thus increased the blood flow with decreasing the intracranial pressure and blood pressure. These effects stanches the epistaxis collectively.

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