• Title/Summary/Keyword: Spoke

Search Result 189, Processing Time 0.033 seconds

Numerical Study of Face Plate-Type EPB Shield TBM by Discrete Element Method (개별요소법을 활용한 면판형 토압식 쉴드TBM의 수치해석 연구)

  • Lee, Chulho;Chang, Soo-Ho;Choi, Soon-Wook;Park, Byungkwan;Kang, Tae-Ho;Sim, Jung Kil
    • Journal of the Korean Geosynthetics Society
    • /
    • v.16 no.4
    • /
    • pp.163-176
    • /
    • 2017
  • The Discrete Element Method (DEM) has been widely used in civil engineering as well as various industrial fields to simulate granular materials. In this study, DEM was adopted to predict the performance of the face plate-type earth pressure balance (EPB) shield TBM (Tunnel Boring Machine). An analysis of the TBM excavation performance was conducted according to two pre-defined excavation conditions with the different rotation speeds per minute (RPM) of the cutterhead. The TBM model which was used in this study has a 6.64 m of diameter and six spokes. Also, 37 precutters and 98 scrapers at an each spoke were modeled with a real-scale specification. From the analysis, compressive forces at the cutterhead face, shield and cutting tools, resistant torques at the cutterhead face, muck discharge rate and accumulated muck discharge by the screw auger were measured and compared.

In vivo Angiogenic Activity of Dichloromethane Extracts of Aloe vera Gel

  • Lee, Myoung-Jin;Yoon, Soo-Hong;Lee, Seung-Ki;Chung, Myung-Hee;Park, Young-In;Sung, Chung-Ki;Choi, Jae-Sue;Kim, Kyu-Won
    • Archives of Pharmacal Research
    • /
    • v.18 no.5
    • /
    • pp.332-335
    • /
    • 1995
  • The angiogenic activity of Aloe vera (Aloe baradensis), known as a good healing plant, was investigated. We have extracted and fractionated dichloromethane extract (G1M1D1) and methanol soluble fraction of dichloromethane extract (G1M1D1M1) which contain low-molecular weight substances of Aloe vera gel. G1M1D1 and G1D1M1 fractions induced a radially arranged, spoke-sheel-like vasculature in chick embryo chorioallantoic membrane (CAM) assay. The angiogenic activity was dose-dependent and the angiogenic pattern in the CAM assay. The angiogenic activity was dose-dependent and the angiogenic pattern in the CAM assay was very similar to that of phorbol 12-myristate-13-acetate (PMA) used as a positive control. The modified CAM assay, e simple and accurate quantitating method, was used to quntitate the angiogenic activity of G1D1M1 fraction. Application of G1M1D1M1 fraction ($100\mug/egg$) resulted in much more intense angiogenesis than in control while slightly less intense angiogenesis than in PMA (100 ng/egg).

  • PDF

A Study on the Transformation in Design Process of Ronchamp Chapel (롱샹 성당의 설계 변형 과정 연구)

  • Lee, Jeong-Kyu
    • Journal of architectural history
    • /
    • v.8 no.1 s.18
    • /
    • pp.81-94
    • /
    • 1999
  • This Study aims at searching the meanings in the creative process of Ronchamp chapel by analyzing the drawings of the site, plan, section and elevation in chronological order. The origins of his architectural creation are identifying with the site(memories of Acropolis), analogies of crab shell, air plane wing and hydraulic dams. The architect informed himself about the site ,the tradition of pilgrimage associated with the place, and its devotion to the Holy Virgin; he looked into the rituals of the Catholic religion, spoke with ecclesiastics; he studied and annotated a monograph devoted to the site of Ronchamp. Also ,the plan required that it be possible to collect rainwater, since such was rare on the hill. In the first design phase, overall conception of building was carried out in the sketches and drawings from June 1950 to November 1950. The second phase in the elaboration of the project was from January 1951(at which time preliminary project was presented to the Commission of Holy Art) to April 1953. The modifications made were in response to opinions expressed by the patrons. The building moved to east and gargoyle moved to west, then, the elevations of north and west were changed. He designed the artificial land and bell tower from the first phase even after the beginning of construction ,he wanted them to be built .But they were not constructed, so the outer space for rituals of religion had no tension. I concluded that Le Corbusier had gifted ability and efforts to create spontaneous birth(after incubation) of the whole work, and the execution of drawings itself. He devoted himself to accomplish the project in spite of the change in situation or by clients.

  • PDF

Intonation Training System (Visual Analysis Tool) and the application of French Intonation for Korean Learners (컴퓨터를 이용한 억양 교육 프로그램 개발 : 프랑스어 억양 교육을 중심으로)

  • Yu, Chang-Kyu;Son, Mi-Ra;Kim, Hyun-Gi
    • Speech Sciences
    • /
    • v.5 no.1
    • /
    • pp.49-62
    • /
    • 1999
  • This study is concerned with the educational program Visual Analysis Tool (VAT) for sound development for foreign intonation using personal computer. The VAT can run on IBM-PC 386 compatible or higher. It shows the spectrogram, waveform, intensity and the pitch contour. The system can work freely on either waveform zoom in-out or the documentation of measured value. In this paper, intensity and pitch contour information were used. Twelve French sentences were recorded from a French conversational tape. And three Korean participated in this study. They spoke out twelve sentences repeatly and trid to make the same pitch contour - by visually matching their pitcgh contour to the native speaker's. A sentences were recorded again when the participants themselves became familiar with intonation, intensity and pauses. The difference of pitch contour(rising or falling), pitch value, energy, total duration of sentences and the boundary of rhythmic group between native speaker's and theirs before and after training were compared. The results were as following: 1) In a declarative sentence: a native speaker's general pitch contour falls at the end of sentences. But the participant's pitch contours were flat before training. 2) In an interrogative: the native speaker made his pitch contours it rise at the end of sentences with the exception of wh-questions (qu'est-ce que) and a pitch value varied a greath. In the interrogative 'S + V' form sentences, we found the pitch contour rose higher in comparison to other sentences and it varied a great deal. 3) In an exclamatory sentence: the pitch contour looked like a shape of a mountain. But the participants could not make it fall before or after training.

  • PDF

Dynamic Routing Interworking Method for Integrating Terrestrial Wireless Backbone Network and Satellite Communications System (지상 무선 백본망과 위성 통신망 통합을 위한 동적 라우팅 연동 방안)

  • Choi, Jaewon;Jo, Byung Gak;Kim, Ki Young;Park, KyoungYoul;Lee, Ju Hyung;Han, Joo Hee;Han, Yeesoo
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.19 no.5
    • /
    • pp.645-653
    • /
    • 2016
  • The terrestrial wireless backbone network and satellite communications system have been independently developed depending on their own purposes and operational concepts, which results in different characteristics in terms of network architecture and routing protocol operation. In this paper, we propose a method for structurally integrating them in consideration of routing mechanism in an autonomous system. Our approach is that the routers of satellite network operate the OSPF in PTP mode on their interfaces connected to the routers of terrestrial wireless backbone network with grid connectivity, whereas the OSPF in satellite network whose topology is of hub-spoke type runs in NBMA mode. We perform some simulations to verify that the satellite communications system can be integrated and interwork with the terrestrial wireless backbone network by our proposed approach. From simulation results, it is also found that the increases of network convergence time and routing overhead are acceptable.

A study on Value and Application of Mobile Harbor in Terms of Coastal Transportation (모바일하버(Mobile Harbor)의 가치와 활용방안에 대한 연구 - 연안운송 중심으로 -)

  • Shin, Chang-Hoon;Jeong, Su-Hyun;Park, Soo-Nam
    • Journal of Navigation and Port Research
    • /
    • v.34 no.3
    • /
    • pp.221-228
    • /
    • 2010
  • As container traffic is increasing, the introduction of mega-vessel has had a significant impact on the ports and terminals business. This movement of container shipping has led to intensely competitive environment among ports, so substantial pressures to develop new container ports or to expand existing ones, have been grown. However, it requires a huge investment, especially cost and time, to overcome environmental, geographical and financial restrictions generated from developing a port. This study addressed the Mobile Harbor, the new concept of marine logistics system as an alternative strategy. We performed an economic analysis on the introduction of the Mobile Harbor in coastal transport sector and also a sensitivity analysis to examine the effects of changing factors related on the economic evaluation. We have examined the value and application of Mobile Harbor as a preliminary study, which may contribute to further studies on the Mobile Harbor.

System Architecture Design and Policy Implications on the e-Marketplace for Telecom Bandwidth Trading (Telecom Bandwidth Trading을 위한 시스템 아키텍처 설계와 거래시장 모형)

  • Kim, Do-Hoon
    • Journal of the Korea Society of Computer and Information
    • /
    • v.12 no.4
    • /
    • pp.257-267
    • /
    • 2007
  • Bandwidth Trading(BT) represents a potential market with over 1 trillion USD across the world and high growth potential. BT is also likely to accelerate globalization of the telecommunications industry and massive restructuring driven by unbundling rush. However, systematic researches on BT remain at an infant stage. This study starts with structure analysis of the Internet industry, and discusses significance of Internet interconnection with respect to BT issues. We also describe the bandwidth commoditization trends and review technical requirements for effective Internet interconnection with BT capability. Taking a step further, this study explores the possibility of improving efficiency of network providers and increasing user convenience by developing an architectural prototype of Hub-&-Spoke interconnection model required to facilitate BT. The BT market provides an innovative base to ease rigidity of two-party contract and increase service efficiency. However, as fair, efficient operation by third party is required, this research finally proposes an exchanging hub named NIBX(New Internet Business eXchange).

  • PDF

Kim Soo-Young and the Critical Reception of Modernism in Korea (모더니즘의 비판적 수용)

  • 이승훈
    • Lingua Humanitatis
    • /
    • v.1 no.2
    • /
    • pp.3-20
    • /
    • 2001
  • The concept of "modernism" has always posed problems in definition from the beginnings of "early-modernism" to our age of post-modernism and multi-culturalism. And yet, the concept has been consistently aligned with the search for new paradigms of thinking about "modernity" as the age experiences it. In this sense, this study tries to explain the meaning of the term "modern," why it still matters in the study of literature, and how to apply it to the examination of Kim Soo-Young′s poems. Kim is one of the leading poets who understood the importance of modernism in the development of Korean modern poetry. But, despite his dedication to the western literary style and modernism, Kim also attempted the renewal of traditional Confucian thought in his poems. The result of such efforts can be seen in poems such as "Difficulties of Confucius ′Everyday Life," in which Kim tries to juxtapose the ancient life of Confucius with life in a much-westernized modern Korea. Another poem "Grass" shows his eagerness to transform traditional eastern aesthetics into a new mode of thinking that encompasses both the influence of the west and changes in 20th-century Korea. Through the study of Kim′s poems in relation to the critical reception of modernism in Korea, we can conclude the following: that Kim led the modernist movement in Korea; that modernism still matters in post-modern Korean literature; and that, because Kin tried to bring together the ideas of western modernism and traditional Confucianism, his poetry not only spoke to his own time but speaks also to our multi-cultural age.

  • PDF

North Korea's nuclear and missile development and our countermeasures (북한의 핵 및 미사일 개발과 우리의 대응방안)

  • Lee, Hyun Hee;Kim, Gyu Nam
    • Convergence Security Journal
    • /
    • v.17 no.2
    • /
    • pp.127-135
    • /
    • 2017
  • Today, Kim Jong-un, the third-hereditary regime in North Korea, is committing Nuclear Provocation more aggressively than the past when Kim Il-sung and Kim Jong-il dominated. Past South Korea government had suggested plans to restrain the provocation from North Korea and bring stabilization in the Korean Peninsula. However, consequentially it was limited to the primary role of the President. When President Trump takes over the government in February 2017, it has attracted the expectation about the issues occurred on the Korean Peninsula due to the pledge that he promised during the presidential election and his govern style. However, various speeches about the Korean Peninsula that he spoke recently made situations depressed about what South Korean currently encounters. Furthermore, previous regime in North Korea has laid the foundation for Kim Jong-un to be obsessed more on the nuclear and missile which has led him to provoke more imprudently by highlighting the light weight, advanced, and various kinds of nuclear and missiles. Thus, we would like to propose counter measures in order for South Korean government to handle and solve the issues that they encounters by themselves based on North Korea's Nuclear Provocation instead of relying on other countries to get involved and help.

Reliable Hub Location Problems and Network Design (신뢰성에 기반한 허브 입지 모델과 네트워크 디자인)

  • Kim, Hyun
    • Journal of the Economic Geographical Society of Korea
    • /
    • v.12 no.4
    • /
    • pp.540-556
    • /
    • 2009
  • The hub and spoke network is a critical network-based infrastructure that is widely applied in current transportation and telecommunications systems, including Internets, air transportation networks and highway systems. This main idea of hub location models is to construct a network system which achieves the economy of scale of flows. The main purpose of this study is to introduce new hub location problems that take into account network reliability. Two standard models based on assignment schemes are proposed, and a minimum threshold model is provided as an extension in terms of hub network design. The reliability and interaction potentials of 15 nodes in the U.S. are used to examine model behaviors. According to the type of models and reliability, hubs, and minimum threshold levels, relationships among the flow economy of scale, network costs, and network resiliency are analyzed.

  • PDF