• 제목/요약/키워드: Change inclination

검색결과 252건 처리시간 0.024초

Acceleration data and shape change characteristics of a gravity quay wall according to inclination condition grades

  • Su-Kyeong Geum;Jong-Han Lee;Dohyoung Shin;Jiyoung Min
    • Structural Engineering and Mechanics
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    • 제90권6호
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    • pp.591-600
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    • 2024
  • This study investigated the acceleration response and shape change characteristics of a gravity quay wall according to the magnitude of the applied acceleration. The quay wall was defined as a port facility damaged by the Kobe earthquake. Four experimental scenarios were established based on the inclination condition grades, considered to be a significant defect factor in the quay wall. Then, the shaking table test was conducted using scaled-down quay wall models constructed per each scenario. The ground acceleration was gradually increased from the peak ground acceleration (PGA) of 0.1 g to 0.7 g. After each ground acceleration test, acceleration installed on the wall and backfill ground and inclination on the top of the wall were measured to assess the amplification of peak response acceleration and maximum response amplitude and the change in the inclination of the quay wall. This study also analyzed the separation of the quay wall from the backfill and the crack pattern of the backfill ground according to PGA values and inclination condition grades. The result of this study shows that response acceleration could provide a reasonable prediction for the changes in the inclination of the quay wall and the crack generation and propagation on the backfill from a current inclination condition grade.

레일 경좌 변화에 따른 곡선부 통과열차의 주행안전성 해석 (Running Safety Analysis of Railway Vehicle passing through Curve depending on Rail Inclination Change)

  • 김문기;엄범규;이희성
    • 한국소음진동공학회논문집
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    • 제23권3호
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    • pp.199-208
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    • 2013
  • So far today, there is a speed limit by the radius of curve based on operation regulation in domestic railway, however a study for the maximum running speed at the curved section without any derailment would be necessary. The two major factors related to the running safety of railway vehicle are classified as the railway vehicle condition and the track condition. In terms of the rail inclination among many other factors, the determination of rail inclination within the possible limit is necessary for the geometrical structure of the optimum track. The disregard of the geometrical parameter related to the rail inclination may cause a serious problem to the running safety of railway vehicle. This study is focusing on the analyzing of running safety regard to the change of rail inclination among the many other parameters to improve derailment safety, so that there is an affection analysis of the running safety regard to the change of rail inclination in the ideal and geometric track condition. Also There is an affection analysis of the running safety regard to the simultaneous change of rail inclination and the running speed at the curved section. According to analysis results of running safety, In case that the left and right rail inclination are 1/40, the running safety of this condition defined than other conditions. Also, the rail inclination of conventional lines is 1/40, Therefore, the railway vehicle passing through curve is safe when the railway vehicle runs in conventional lines.

Le Fort I 골절단술에서 posterior impaction의 양과 occlusal plane angle, incisor inclination의 변화 관계에 관한 연구 (Study about the relationship between the amount of posterior impaction and the change of occlusal plane angle and incisor inclination in Le Fort I osteotomy)

  • 김복주;김민구;김정한;김철훈
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제36권5호
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    • pp.375-379
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    • 2010
  • Introduction: In the management of dentofacial deformities, variable movement of the maxilla can be made possible by a Le Fort I osteotomy. Posterior impaction of the maxilla necessary for rotation of the maxillomandibular complex enhances the functions and esthetic results. In cases of posterior impaction of the maxilla, an increase in the figure of the occlusal plane angle and incisor inclination can occur. This study reports the relationship between the amount of posterior impaction and the change in the occlusal plane angle and incisor inclination in a Le Fort I osteotomy by preoperative and postoperative lateral cephalograms. Materials and Methods: Twenty patients who had undergone orthognathic surgery in Dong-A University Medical Center participated in this study. Lateral cephalometrics, within 3 weeks prior to surgery and 3 days after surgery, were used for analysis. Pre and postoperative measurements of the occlusal plane angle and incisal inclination based on the Frankfort horizontal (FH) plane were performed. X and Y were defined as the amount of vertical change in the upper incisor tip and the amount of vertical change in the upper first molar mesial cup tip through the operation. The amount of final posterior maxillary impaction was determined by subtracting Y from X, which is the difference in vertical height. According to the amount of posterior maxillary impaction, the change in the occlusal plane angle and incisal inclination was measured. Results: The average posterior maxillary impaction was 2.91 mm and the average change in the occlusal plane angle and incisal inclination was $6.54^{\circ}$after surgery. As a result, each mm of posterior maxillary impaction changed the occlusal plane angle and incisal inclination by $2.25^{\circ}$. Statistically, there was high significance. Two cases were observed: one with the same amount of posterior maxillary impaction performed on both the right and left showing $2.20^{\circ}$, and the other with a different amount of posterior maxillary impaction performed showing $2.35^{\circ}$. In this case, there was no significance difference between the two cases. Conclusion: Each mm of posterior maxillary impaction changes the occlusal plane angle and incisal inclination by an average of $2.25^{\circ}$. In posterior maxillary impaction, there was no significant difference in the amount of change in the occlusal plane angle and incisal inclination regardless of whether there was an equal amount of posterior maxillary impaction on both sides. This study is expected to help in the presurgical orthodontic preparation and presurgical treatment planning.

자기 주도적 수업이 수학적 태도에 미치는 영향 (The influence of the student-centered classes on the change in the mathematical attitude)

  • 남영목;임석훈
    • 한국학교수학회논문집
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    • 제3권2호
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    • pp.37-46
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    • 2000
  • This study is to analyze the mathematical, affective attitude and inclination which have already been formed in the learners and to find what kinds of changes occur in the mathematical, affective attitude and inclination after the student-centered multimedia classes in which students present and discuss the questions of their own making. The purpose of this study is to find 1. Can we change the mathematical, affective attitude and inclination which have already been formed in the learners\ulcorner 2. If we can, how further can we change them\ulcorner To find a solution to these questions, I have transformed, to meet the purpose of this study, the questions which have already been approved and have used them. As a result of it, there has been a considerable change in the mathematical, affective attitude and inclination of the students about some questions.

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곡선부 통과열차의 레일 경좌 변화에 따른 주행안전성 해석 (A Running Safety Analysis of Railway Vehicle passing through Curve According to Rail Inclination Change)

  • 손명선;엄범규;강부병;이희성
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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    • pp.1922-1928
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    • 2011
  • The rail inclination produces a wider bearing area between the wheel and the rail by moving the wheel rail contact area away from the gauge towards the centre of the railhead, thus improving the wear pattern of the railhead and wheel treads. It is essential to keep the rail inclination within the allowable range to ensure optimum track geometry. Neglecting the rail inclination geometrical parameters in a track quality evaluation can cause safety of railway vehicle and serviceability problems. In this paper, we examined the effect of the rail inclination in general geometry state of the railway track using VI-Rail and analyzed running safety when the railway vehicle passing through curves depending on change of the rail inclination and running speed.

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원통형 용기내의 상변화물질에서의 응고 열전달에 관한 연구 (경사각 변화의 영향) (A Study on Heat Transfer Phenomena during Solidification in a Circular Tube Containing Phase Change Material (Effect of Inclination))

  • 송하진;김영중;오수철;임장순
    • 설비공학논문집
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    • 제6권3호
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    • pp.182-192
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    • 1994
  • This paper focuses on the investigation of the heat transfer phenomena that occur inside the cylindrical tube. The inclination of the tube is adopted as a principal parameter varying from vertical to horizontal. The phase change material employed in this experiment is 99 percent pure n-docosane paraffin($C_{22}$ $H_{46}$). It is found that the amount of solidified mass during a prescribed solidifying period is not sensitive to the inclination of the tube but to the local layer thickness. It is studied that the latent energy is the largest contributor to the total extracted energy. The sensible energy($E_{s1}$, $E_{s2}$, $E_{s3}$) may not be negligible at the large wall-subcooling and initial-liquid-superheating, also at the first step of solidifying.

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Clinical effects of different prescriptions on the inclination of maxillary and mandibular incisors by using passive self-ligating brackets

  • Savoldi, Fabio;Sangalli, Linda;Ghislanzoni, Luis T. Huanca;Dalessandri, Domenico;Gu, Min;Mandelli, Gualtiero;Paganelli, Corrado
    • 대한치과교정학회지
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    • 제52권6호
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    • pp.387-398
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    • 2022
  • Objective: Controlling the incisal inclination is fundamental in orthodontics. However, the relationship between the inclination prescription and its clinical outcome is not obvious, and the incisal inclination changes generated by different bracket prescriptions were investigated. Methods: Twenty-eight non-extraction dental Class II patients (15 females, 13 males; mean age = 12.9) were retrospectively analyzed. Patients were treated using passive self-ligating fixed appliances with three inclination prescriptions for maxillary incisors (high, standard, low), and two for mandibular incisors (standard, low). Clinical outcomes were compared among different prescriptions, and regression analysis was used to explain the effects of bracket prescriptions and to understand the prescription selection criteria (α = 0.05). Results: For maxillary central incisors, low and high prescriptions were related to linguoversion (p = 0.046) and labioversion (p = 0.005), respectively, while standard prescription maintained the initial dental inclination. Maxillary lateral incisors did not show significant changes. For mandibular incisors, low prescription led to linguoversion (p = 0.005 for central incisors, p = 0.010 for lateral incisors), while standard prescription led to labioversion (p = 0.045 for central incisors, p = 0.005 for lateral incisors). The factors affecting inclination changes were the imposed change and selected prescription, while prescription selection was influenced by the initial dental inclination and initial intercanine distance. Conclusions: The direction of correction of incisal inclination can be controlled by choosing a certain prescription, but the final inclination may show limited consistency with it. The amount of imposed inclination change was the most relevant predictor of the clinical outcome.

Dynamic response of layered hyperbolic cooling tower considering the effects of support inclinations

  • Asadzadeh, Esmaeil;Alam, Mehtab;Asadzadeh, Sahebali
    • Structural Engineering and Mechanics
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    • 제50권6호
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    • pp.797-816
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    • 2014
  • Cooling tower is analyzed as an assembly of layered nonlinear shell elements. Geometric representation of the shell is enabled through layered nonlinear shell elements to define the different layers of reinforcements and concrete by considering the material nonlinearity of each layer for the cooling tower shell. Modal analysis using Ritz vector analysis and nonlinear time history analysis by direct integration method have been carried out to study the effects of the inclination of the supporting columns of the cooling tower shell on its dynamic characteristics. The cooling tower is supported by I-type columns and ${\Lambda}$-type columns supports having the different inclination angles. Relevant comparisons of the dynamic response of the structural system at the base level (at the junction of the column and shell), throat level and at the top of the tower have been made. Dynamic response of the cooling tower is found to be significantly sensitive to the change of the inclination of the supporting columns. It is also found that the stiffness of the structure system increases with increase in inclination angle of the supporting columns, resulting in decrease of the period of the structural system. The participation of the stiffness of the tower in structural response of the cooling tower is fund to be dependent of the change in the inclination angle and even in the types of the supporting columns.

경지 균평 작업을 위한 자동 표고 측정에 관한 연구 (A Study on the Automatic Level Measurement for Land Leveling)

  • 김종안;김수현;곽윤근
    • Journal of Biosystems Engineering
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    • 제22권3호
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    • pp.269-278
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    • 1997
  • An automatic level measurement system was developed to level the land fer direct seeding of rice. A laser transmitter/receiver set was used to measure land-level. The inclination error occurred in level measurement on irregular land surface could be compensated by attaching rotating mass. The level measuring experiments were performed on three kinds of different shapes(step, random, sine). This system could accurately measure step level of which amplitude was 40mm in 0.5s, random level change within $\pm$ 5mm maximum measurement error, and sine level change of which spatial frequency was 0.5m-1. To verify performance of the inclination error compensation system, frequency transfer function(acceleration input vs. inclination error) was computed by spectral analysis. The inclination error was decreased about 20㏈ by error compensation system.

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튜브 경사각이 풀핵비등열전달에 미치는 영향 (Effects of Tube Inclination Angle on Nucleate Pool Boiling Heat Transfer)

  • 강명기
    • 대한기계학회논문집B
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    • 제26권1호
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    • pp.116-124
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    • 2002
  • An experimental parametric study of a tubular heat exchanger has been carried out far the saturated water at atmospheric pressure to determine effects of tube inclination on pool boiling heat transfer. For the analysis, seven inclination angles(0°, 15°, 30°, 45°, 60°, 75°, and 90°) and two tube diameters(12.7 and 19.1 mm) were tested. According to the results, inclination angles result in very much change on pool boiling heat transfer. As the inclination angle is around horizontal or vertical, maximum or minimum heat transfer is expected, respectively. For the same wall superheat(about 5.5K) the ratio between two heat fluxes fur $\theta$ =15° and 75° has the value of more than five when the tube diameter is 12.7 mm and heat flux is increasing.