• 제목/요약/키워드: Asymmetry effect

검색결과 383건 처리시간 0.029초

지진동을 받는 3층 강재 프레임 구조물의 지진 거동 (Seismic Behavior of 3-Story Steel Frame Structures Subjected to Ground Motions)

  • 허종완;차영욱
    • 한국강구조학회 논문집
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    • 제28권6호
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    • pp.383-394
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    • 2016
  • 두본 연구에서는 축소된 3층의 강재 프레임 구조물에 실제 지진동 데이터를 사용하여 고등적인 3차원 유한요소 해석을 통해 거동을 예측하고 손상을 평가하고자 한다. 비선형 동적 해석에서 구조물의 연약층(Soft Story)의 효과와 비대칭성(Asymmetry)을 고려하기 위하여 기둥의 단면적을 축소 시켜 기둥을 손상시키고 집중 질량을 슬래브에 가하여 프레임 모델을 설계를 하였다. 해석 결과 분석을 통해 프레임 구조물의 손상은 중량의 대칭성 보다는 기둥의 손상과 연약층의 존재에 의해서 결정됨을 본 연구를 통하여 재확인할 수 있다.

A SIMPLE GRANULE MODEL AND ITS EFFECT ON SPECTRAL LINE ASYMMETRY

  • KIM YONGCHEOL
    • 천문학회지
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    • 제31권2호
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    • pp.77-87
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    • 1998
  • The accumulated knowledge of the influence of solar granulation on spectral lines, i.e. their asymmetry, provides a key to analyze stellar spectral line asymmetries. In this paper, a simple line synthesis using a simple 'model' of granulation was calculated. By adjusting the properties of the granule model, the observed imprints of convection on spectral lines can be reproduced. Since we depict convective flows using a continuous function rather than using a few components of flows (cf. Gray and Toner 1985, 1986; dravins 1990), we were able to identify which components of convection are important in line bisector shapes. The results of this study can be summarized as follows: Firstly, the intensity contrast (i.e. temperature fluctuation), and the area coverage of up- and down-flows are the two important factors which determine the line bisector shapes. Secondly, on the contrary to the assumption of other studies, the effect of horizontal flows is non-negligible. This exercise provides a qualitative understanding of the effect of convection on spectral lines. This knowledge serves as a guideline for understanding the characteristic difference in convection for stars on either side of the 'Granulation Boundary' (Gray 1982; Gray and Nagel 1989).

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전계가 가해진 절연유의 유동대전 특성 고찰 (Study on the Streaming Electrification of Insulating oil Under Electricfield)

  • 허창수;정중일
    • E2M - 전기 전자와 첨단 소재
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    • 제10권4호
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    • pp.334-341
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    • 1997
  • Streaming electrification on insulating paper and pressboard under D.C. and A.C. electric field was investigated by using paper tubes and oil circulation apparatus. At first, flowing of static charges as measured with no electric field. As the temperature of oil increased, the measured current curve hows peak. As the velocity increased, it shows increasing exponential curve. Then, we applied A.C. and D.C. electric field on paper tube and the current from relaxation tank to earth was measured, which other factors such as temperature and velocity were varied like case of no electric field. The ions in oil carry the charges. So electric field makes asymmetry effect, and electrophoretic effect on ions in oil. We find that as the electric field intensity increased, the charges which were made by electric double layer were increased. The charge vs. velocity curve made peak point at a velocity.

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요가수련전후 한발서기자세의 좌우대칭력 평가 (Evaluation for Symmetry Ability of One Leg Standing Pose before and after Yoga Training)

  • 유실
    • 한국운동역학회지
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    • 제24권4호
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    • pp.391-397
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    • 2014
  • The purpose of this work is to biomechanically study the effect of the one leg standing pose in yoga.. The work have been done through the evaluation for the left and right symmetry ability of one leg standing pose in the before and after yoga training for the 14 female yoga subject group (height: $164.3{\pm}4.4cm$, mass: $53.4{\pm}6.4kg$, year: $20.0{\pm}0.49yrs$) participated in this experiment. The motions of one leg standing pose were captured with Vicon system and the parameters were calculated with Visual-3D and Ground reaction force system. The results were as followed; - Front and backward COPsd did not show the significant difference, compared the before training with the after. - Left and right COPsd showed the significant difference (p<0.05), compared the before training with the after. - COP distance showed the significant difference (p<0.01), compared the before training with the after. - The asymmetry index of front and backward COPsd did not show the significant difference, compared the before training with the after. - The asymmetry index of left and right COPsd did not show the significant difference, compared the before training with the after. - The asymmetry index of COP distance showed the significant difference (p<0.01), compared the before training with the after. Therefore, the yoga training demonstrated the stable improvement in the one leg standing pose of inferior feet and the positive effect to the left and right symmetry ability.

Comparison of the bite force and occlusal contact area of the deviated and non-deviated sides after intraoral vertical ramus osteotomy in skeletal Class III patients with mandibular asymmetry: Two-year follow-up

  • Kwon, Hyejin;Park, Sun-Hyung;Jung, Hoi-In;Hwang, Woo-Chan;Choi, Yoon Jeong;Chung, Chooryung;Kim, Kyung-Ho
    • 대한치과교정학회지
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    • 제52권3호
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    • pp.172-181
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    • 2022
  • Objective: The objectives of this study were to compare the time-dependent changes in occlusal contact area (OCA) and bite force (BF) of the deviated and non-deviated sides in mandibular prognathic patients with mandibular asymmetry before and after orthognathic surgery and investigate the factors associated with the changes in OCA and BF on each side. Methods: The sample consisted of 67 patients (33 men and 34 women; age range 15-36 years) with facial asymmetry who underwent 2-jaw orthognathic surgery. OCA and BF were taken before presurgical orthodontic treatment, within 1 month before surgery, and 1 month, 3 months, 6 months, 1 year, and 2 years after surgery. OCA and BF were measured using the Dental Prescale System. Results: The OCA and BF decreased gradually before surgery and increased after surgery on both sides. The OCA and BF were significantly greater on the deviated side than on the non-deviated side before surgery, and there was no difference after surgery. According to the linear mixed-effect model, only the changes in the mandibular plane angle had a significant effect on BF (p < 0.05). Conclusions: There was a difference in the amount of the OCA and BF between the deviated and non-deviated sides before surgery. The change in mandibular plane angle affects the change, especially on the non-deviated side, during the observation period.

산후 우울감을 보이는 산모에서 나타나는 전두엽 뇌파 비대칭에 대한 음악의 영향 (The Effects of Music on the Frontal EEG Asymmetry of the Mothers with Postpartum Blues)

  • 임성진;신철진
    • 생물정신의학
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    • 제18권3호
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    • pp.134-140
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    • 2011
  • Objectives Postpartum blues is known to be a major risk factor for postpartum depression and can be associated with the problems of language skills, behaviors or learning skills of their children. Therefore, it is very important for clinicians to evaluate precisely and control postpartum blues. Recent studies have found that music has an effect on depressive mood and the frontal EEG asymmetry of the patients with depression. The purpose of this study was to find out the effects of music on the frontal EEG asymmetry of the mothers with postpartum blues. Method Among one hundred and seventy mothers assessed with Korean version of the Edinburg Postnatal Depression Scale (EPDS), nine mothers with postpartum blues (EPDS ${\geq}$ 10) as postpartum blues group and nine non-depressive mothers (EPDS < 10) as non-depressive mother group were included. Ten non-labored, non-depressive women were also included as a normal control group. The subjects were evaluated with the State Trait Anxiety Inventory (STAI)-X1, the Visual Analogue Scale (VAS) and the Depression Adjective Checklist-Korean version (K-DACL) and EEG twice before and after the music sesssion with the length of twenty minutes and thirty two seconds. The statistical analyses were done for A1 score (log R - log L) which were computed from the alpha powers at F3 and F4. Results No significant difference was noted in demographic data among all three groups. The postpartum blues group had higher scores in the STAI-X1, the VAS and the K-DACL compared to the other groups at baseline, and their A1 scores were lower than those of only normal controls. There was a statistically significant increase of A1 score only in the postpartum blues group after the music session. Conclusion This study suggests that the mothers with postpartum blues may have a frontal EEG asymmetry which is possibly associated with their depressive mood, and the music session can affect the frontal asymmetry positively.

K-IFRS에 따른 유형자산 재평가 정보가 정보비대칭 감소에 미치는 영향 (The Effect of PP&E Revaluation under K-IFRS on Information Asymmetry)

  • 신찬휴
    • 디지털융복합연구
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    • 제16권12호
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    • pp.163-173
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    • 2018
  • 본 연구는 K-IFRS 의무 도입 이전 기간과 이후 기간을 각각의 표본으로 하여, 해당 기간에 자산재평가 이전과 이후의 정보비대칭 차이를 검증하고자 한다. 효율적 시장가설에 따르면 자본시장은 유형자산의 실제가치를 이미 인식하여 평가에 반영할 수 있고, 이러한 경우 유형자산 재평가는 자본시장에 추가적인 정보가 되지 못하고 단순히 비용만 발생시키는 행위가 된다. 본 연구에서는 유형자산 재평가 이후에 자본시장의 정보비대칭이 유의하게 감소하였는지 검증하고자 하며, K-IFRS에 따른 유형자산 재평가는 2008년부터 조기도입이 가능했으므로 K-IFRS 도입 이전과 이후로 표본을 분할하여 각각의 기간에 대해 검증하고자 한다. 연구 결과, K-IFRS 도입 이전 표본은 유형자산 재평가가 자본시장의 정보비대칭을 감소시키는 것을 확인하였으나, K-IFRS 도입 이후 표본은 유형자산 재평가가 자본시장의 정보비대칭을 감소시키지 못하는 것을 확인하였다. 이러한 연구 결과는 자본시장에서 유형자산 재평가에 대해 윈도우드레싱(window dressing)으로 판단하고 있다는 것을 지지하는 실증적 증거를 제공한다.

요통환자에게 굴곡신연기법을 시술한 전후의 표면근전도 비교 연구 (The study on the asymmetry ratio of surface EMG in low back pain groups - before and after flexion-distraction technique)

  • 황의형;김정연
    • 대한추나의학회지
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    • 제5권1호
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    • pp.243-249
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    • 2004
  • Objectives : This study is to evaluate the effect of flexion-distraction technique by measuring surface EMG in low back pain groups. Methods : 5 low back pain patients' constact time, power, fatigue, recovery of muscle were measured before and after flexion-distraction technique. Results : The asymmetry ratio of surface EMG in low back pain groups were Increased, but decreased after flexion-distraction technique. Conclusions : Surface EMG might be used for evaluating the effect of flexion-distraction technique.

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