• 제목/요약/키워드: Structure movement

검색결과 1,199건 처리시간 0.027초

Numerical and experimental study of multi-bench retained excavations

  • Zheng, Gang;Nie, Dongqing;Diao, Yu;Liu, Jie;Cheng, Xuesong
    • Geomechanics and Engineering
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    • 제13권5호
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    • pp.715-742
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    • 2017
  • Earth berms are often left in place to support retaining walls or piles in order to eliminate horizontal struts in excavations of soft soil areas. However, if the excavation depth is relatively large, an earth berm-supported retaining system may not be applicable and could be replaced by a multi-bench retaining system. However, studies on multi-bench retaining systems are limited. The goal of this investigation is to study the deformation characteristics, internal forces and interaction mechanisms of the retaining structures in a multi-bench retaining system and the failure modes of this retaining system. Therefore, a series of model tests of a two-bench retaining system was designed and conducted, and corresponding finite difference simulations were developed to back-analyze the model tests and for further analysis. The tests and numerical results show that the distance between the two rows of retaining piles (bench width) and their embedded lengths can significantly influence the relative movement between the piles; this relative movement determines the horizontal stress distribution in the soil between the two rows of piles (i.e., the bench zone) and thus determines the bending moments in the retaining piles. As the bench width increases, the deformations and bending moments in the retaining piles decrease, while the excavation stability increases. If the second retaining piles are longer than a certain length, they will experience a larger bending moment than the first retaining piles and become the primary retaining structure. In addition, for varying bench widths, the slip surface formation differs, and the failure modes of two-bench retained excavations can be divided into three types: integrated failure, interactive failure and disconnected failure.

기계적 필터를 이용한 포신형상 구조물의 진동신호 측정 (Measurement of Vibration Signals of a Gun Barrel Type Structure using Mechanical Filter)

  • 류봉조;구경완
    • 전기학회논문지P
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    • 제59권4호
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    • pp.440-443
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    • 2010
  • This paper deals with the method of vibration measurement of a gun barrel structure using mechanical filter. When a bullet with high speed is moving within a gun barrel type structure with low bending vibration frequencies, it is difficult to measure the bending vibration signals of the structure. For example, noncontact type sensors such as displacement or velocity sensor are not appropriate for the measurement of vibrational signals because of the movement effect of the equipment frame through the moving structures or effect of the ground vibration. One of contact type sensors such as accelerometer is profitable for measurement of vibrational signals because of its wide measurement ranges. In the case of a gun barrel structure including high vibrational signals like shock waves, however, it is necessary to propose vibration measurement method filtering high frequencies. The purpose of the paper is to propose the proper vibrational measurement technique filtering high frequencies of a gun barrel type structure.

Performance Improvement of Delay-Tolerant Networks with Mobility Control under Group Mobility

  • Xie, Ling Fu;Chong, Peter Han Joo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권6호
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    • pp.2180-2200
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    • 2015
  • This paper considers mobility control to improve packet delivery in delay-tolerant networks (DTNs) under group mobility. Based on the group structure in group mobility, we propose two mobility control techniques; group formation enforcement and group purposeful movement. Both techniques can be used to increase the contact opportunities between groups by extending the group's reachability. In addition, they can be easily integrated into some existing DTN routing schemes under group mobility to effectively expedite the packet delivery. This paper is divided into 2 parts. First, we study how our proposed mobility control schemes reduce the packet delivery delay in DTNs by integrating them into one simple routing scheme called group-epidemic routing (G-ER). For each scheme, we analytically derive the cumulative density function of the packet delivery delay to show how it can effectively reduce the packet delivery delay. Then, based on our second proposed technique, the group purposeful movement, we design a new DTN routing scheme, called purposeful movement assisted routing (PMAR), to further reduce the packet delay. Extensive simulations in NS2 have been conducted to show the significant improvement of PMAR over G-ER under different practical network conditions.

객체의 움직임을 고려한 탐색영역 설정에 따른 가중치를 공유하는 CNN구조 기반의 객체 추적 (Object Tracking based on Weight Sharing CNN Structure according to Search Area Setting Method Considering Object Movement)

  • 김정욱;노용만
    • 한국멀티미디어학회논문지
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    • 제20권7호
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    • pp.986-993
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    • 2017
  • Object Tracking is a technique for tracking moving objects over time in a video image. Using object tracking technique, many research are conducted such a detecting dangerous situation and recognizing the movement of nearby objects in a smart car. However, it still remains a challenging task such as occlusion, deformation, background clutter, illumination variation, etc. In this paper, we propose a novel deep visual object tracking method that can be operated in robust to many challenging task. For the robust visual object tracking, we proposed a Convolutional Neural Network(CNN) which shares weight of the convolutional layers. Input of the CNN is a three; first frame object image, object image in a previous frame, and current search frame containing the object movement. Also we propose a method to consider the motion of the object when determining the current search area to search for the location of the object. Extensive experimental results on a authorized resource database showed that the proposed method outperformed than the conventional methods.

싱글PPM 품질혁신 운동과 기업의 만족도에 관한 연구 (A Study of the Single PPM Quality Innovation's Movement and Satisfaction in the Enterprise)

  • 김태성;구일섭
    • 대한안전경영과학회지
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    • 제11권1호
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    • pp.115-120
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    • 2009
  • Single PPM Quality Innovation Movement is originally developed quality program in Korea for supplier's quality level-up since 1995. The quality target is below the 10ppm(parts per million) in outgoing quality and delivered goods plus field claim. This Single PPM Quality Innovation Movement program was conducted to realize the anticipated results not only due to management result level's increasing, but also the company's confidence and competitiveness. This study attempted to find the mutual influences on the participation of the constituent members, satisfaction of the constituent members and results of the management from Single PPM Quality Innovation Movement. The reliance analysis for the measurement material on the questionnaire was verified by Cronbach's alpha coefficient. Participation of the constituent members, satisfaction of the constituent member and result of the management, the influences upon Single PPM improvement degree level were verified through the structural analysis by using SPSS statistic package. The influence evaluation among the groups was evaluated by the structure equation.

A STUDY ON THE FORMATION OF EARLY TURKISH NATIONALISM

  • JEONG, EUN KYUNG
    • Acta Via Serica
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    • 제3권1호
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    • pp.57-83
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    • 2018
  • Historians describe the early years of the 20th century as a period of "nationalism." During this period, Turkish nationalism transformed into a thought movement which emerged to defend Turkish national sovereignty during the collapse of the Ottoman Empire. Approaches towards nationalism in Turkey are based on the idea of national sovereignty and the ideas of national independence that developed subsequently. Nationalism in Turkey first transformed from Pan-Islamism into multinational Ottomanism, and finally developed into Turkish nationalism and patriotism. This process emerged as a movement of self-discovery in the multicultural structure of the Ottoman Empire and transformed into Turkism. The Balkan Wars (1912-1913) destroyed the foundation upon which Ottomanism was based, and led to the rise of Turkish nationalism, in other words, Turkism. The idea of nation in modern terms in the recent history of thought and nationalism subsequently developed based on this idea and emerged with the Turkism movement. Thus, Turkism became the movement of Turks in the empire, combined with political Turkism which was supported by the intellectuals who came to the Ottoman Empire from Russia. In this article, the formation of Turkist movements and the leading intellectuals of Turkish nationalism, who emerged at the end of the 19th century and at the beginning of 20th century in the Ottoman Empire, are investigated in order to examine the historical progress of nationalist approaches in a period in which a new national state was established and improved.

Application of black box model for height prediction of the fractured zone in coal mining

  • Zhang, Shichuan;Li, Yangyang;Xu, Cuicui
    • Geomechanics and Engineering
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    • 제13권6호
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    • pp.997-1010
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    • 2017
  • The black box model is a relatively new option for nonlinear dynamic system identification. It can be used for prediction problems just based on analyzing the input and output data without considering the changes of the internal structure. In this paper, a black box model was presented to solve unconstrained overlying strata movement problems in coal mine production. Based on the black box theory, the overlying strata regional system was viewed as a "black box", and the black box model on overburden strata movement was established. Then, the rock mechanical properties and the mining thickness and mined-out section area were selected as the subject and object respectively, and the influences of coal mining on the overburden regional system were discussed. Finally, a corrected method for height prediction of the fractured zone was obtained. According to actual mine geological conditions, the measured geological data were introduced into the black box model of overlying strata movement for height calculation, and the fractured zone height was determined as 40.36 m, which was comparable to the actual height value (43.91 m) of the fractured zone detected by Double-block Leak Hunting in Drill. By comparing the calculation result and actual surface subsidence value, it can be concluded that the proposed model is adaptable for height prediction of the fractured zone.

앵글씨 분류에 의한 성인 골격구조 및 하악운동량 평가 (The Assessment for Mandibular Movement and Adult Facial Skeletal Structure According to Angle's Classcification)

  • 김재형;김병국;최홍란
    • Journal of Oral Medicine and Pain
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    • 제26권2호
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    • pp.147-156
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    • 2001
  • The purpose of this study was to identify the difference of vertical movement of mandible according to Angle's molar relationship and by skeletal factors affect to vertical movement of mandible. 172(age ranged from 20 to 30) subjects who go to college within territory of Kwangju city without any experience of temporomandibular disorder, extraction and orthodontic treatment. were selected for this study. The subjects were classified into class I(male:30, female:49), class II(male:18, female:24) and class III(male:18, female:33) according to Angle's molar relationship. The distance was measured between incisal edge of maxillary and mandibular central incisor and between bottom of central fossa of maxillary and mandibular 1st molar with ruler. The arch length and width were measured on the diagnostic cast. Cephalometrics were taken and then traced. Landmarks were identified and analyzed. 1. Maximal interincisal opening of male is larger than that of female in class I, class II and class III. Among each group maximal interincisal distance is the largest in class III. Maximal intermolar distance of male is superior to that of female in class I, class II, and class III, but there is no siginficant difference among them. 2. On maximal opening movement of Angle's classification class I and class II, total mandibular length, mandibular ramal length, madibular inferior border length and upper arch width were important variables and facial length, upper arch length and lower arch length had negative relationship to that. On maximal opening movement of Angle's class III, the upper arch length, the lower arch length and anterior facial length were important variables especially when compared with class I and II, and upper arch width had negative relationship. These results suggest that maximal opening movement is affected by facial morphology in all classes, but each group is affected by different facial skeletal variables. Accordingly, facioskeletal variables might be considered as diagnosis and treatment to improve the amount of mouth opening.

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딤플형 내부구조재를 갖는 접합판재의 굽힘 특성연구 (A Study on The Bending Characteristic of Sandwich Sheet Metal with Dimple Type-Inner-Structure)

  • 김흥근;오솔길;유정수;성대용;정완진;김종호
    • 한국금형공학회:학술대회논문집
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    • 한국금형공학회 2008년도 하계 학술대회
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    • pp.31-34
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    • 2008
  • The L-bending of inner-structure bonded sandwich sheet metal is examined to reduce springback and defects of bent parts. The specimen is composed of top and bottom layers and a middle layer with dimple type-inner-structure and each layer is bonded by resistance welding. This specimen with hollow type-inner-structure shows different bending characteristics from the conventional sandwich sheet metals with solid type-inner-structure. The experiments were conducted for two kinds of working conditions, that is, clearance and movement of first bent specimen for second bending. The deformed profile, bend angle and springback were investigated and compared and then the proper working conditions for L-bending of sandwich sheet metal were prosed.

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개폐식 지붕구조의 움직임에 대한 공간구조물의 진동해석 (Vibration Analysis of Space Structure with Retractable Roof)

  • 김기철;강주원;김현수
    • 한국공간구조학회논문집
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    • 제11권1호
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    • pp.113-120
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    • 2011
  • 지붕구조의 개폐가 가능한 체육시설 및 복합시설은 대공간구조물의 장점을 잘 나타내고 있으며 대공간구조물의 전천후 사용이 가능하도록 하였다. 개폐식 지붕구조는 구조형식, 마감재료, 개폐방식에 따라서 매우 다양하며 개폐방식에 따라서 중첩방식, 수평이동방식, 주름접기방식 등으로 구분할 수 있다. 특히 중첩방식이나 수평이동방식에 의한 지붕구조의 움직임은 주행하중, 충격하중, 관성력 및 제동력과 같은 동적하중이 구조물에 가해질 수 있으므로 이에 대한 대공간구조물의 진동해석이 필요할 것으로 사료된다. 지붕구조의 움직임에 의한 주행하중은 이동질량 또는 이동하중으로 적용할 수 있으나 비교적 움직임이 느린 개폐식 지붕구조에 의한 동적하중은 아동하중으로 적용하는 것이 타당하다. 따라서 본 논문에서는 지붕구조의 개폐로 야기되는 이동하중에 대한 새로운 적용방법을 제안하고 이를 이용하여 개폐식 지붕의 개폐속도에 따른 대공간구조물의 진동해석을 수행하였다. 본 논문에서 제안된 등가 이동하중은 지붕구조 개폐에 의한 대공간구조물의 진동해석에 있어서 매우 용이하게 활용할 수 있다.