• Title/Summary/Keyword: 전복 조건

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Structural Evaluation of Spent Fuel Dry Storage Cask (사용후연료 건식 저장용기의 구조평가)

  • 서기석;이재한;강경훈;박성원;정성환
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2003.11a
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    • pp.627-631
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    • 2003
  • In a various regulations and standards related to the spent fuel storage, the storage casks should be designed to sustain the structural integrity under the accident conditions of predicted operation and design criteria. These conditions for the structural evaluation requires the drop, tip-over, wind like tornado and typhoon, flood and earthquake. This paper describes the load cases and conceptual evaluation method for the structural evaluation. Preliminary safety analysis of the concrete storage system were peformed.

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A Study on the Development of Semi-Submersible Drilling Rig with Oil Recovery System

  • Lee, Kwi-Joo;An, Jung-Sun
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2011.06a
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    • pp.399-401
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    • 2011
  • 반잠수식 시추선의 주선체(lower hull)를 세 가지 타입으로 설계하여 주선체에 대한 유체정역학적 계산, 조종성능 및 내항성능 계산 그리고 이론계산을 수행하여 wave distribution과 height도 각각 비교 분석하였다. 주선체의 Convention type, Bulbous bow type, 그리고 Ice breaking type 중 Ice breaking type 선형의 성능이 가장 우수하였다. 다음으로는 반잠수식 시추선의 모든 조건(작업, 이동, 생존)에서 주기둥(column) 또는 주선체(Lower)가 손상되어 부력을 상실했을 시 전복 되지 않도록 고안된 예비부력 기능과 기름 유출 사고시 기름을 회수 할 수 있는 기능을 갖춘 유회수 겸용 예비부력 탱크를 개발하였다.

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Moving Path following and High Speed Precision Control of Autonomous Mobile Robot Using Fuzzy (퍼지를 이용한 자율 이동 로봇의 이동 경로 추종 및 고속 정밀 제어)

  • Lee, Won-Ho;Lee, Hyung-Woo;Kim, Sang-Heon;Jung, Jae-Young;Roh, Tae-Jung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.14 no.7
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    • pp.907-913
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    • 2004
  • The major interest of general mobile robot is making a route and following a maked route. But, In the case of robot that is in need of movement of partial high speed, the condition of dynamic limitation is exist, and in these conditions, it demands controlling against movements we want. In this paper, in respect of the following a route at the situation that don't have the environmental map, that is, unknown environments, to prevent the slide of moving robot or the overturn that can happen for it moves fast, we organize the dynamic condition of limitation using the fuzzy logic, and we obtain more safe and fast route tracing ability by changing the standard velocity. Especially, by modeling the line tracing mobile robot, we design the tracing controller against a realtime changing target, and using the fuzzy optimized velocity limitation controller, we confirm that our robot shows its stable tracing ability by limiting its velocity intelligently against the continuously changing line.

Study on numerical analysis of driftwood generation and behavior by tsunami flow (쓰나미에 의한 유목의 발생과 거동의 수치해석적 연구)

  • Kang, Tae Un;Jang, Chang-Lae
    • Proceedings of the Korea Water Resources Association Conference
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    • 2021.06a
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    • pp.66-66
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    • 2021
  • 2011년에 일본 도호쿠 지방 태평양 해역에서 규모 9.0의 지진이 발생하여 거대한 쓰나미가 일본 본토 해안을 침수시켰다. 이로 인해, 정확한 피해규모가 파악되기 어려울 정도로 막대한 인명과 재산피해를 입게 되었다. 센다이지역의 경우 쓰나미로 인해 해안에 위치한 약 3.8 평방킬로미터의 방풍림이 모두 전복되었고 일부는 유목이 되어 쓰나미와 함께 내륙으로 흘러들어가 곳곳에 퇴적되어 농지를 훼손하고 가옥에 피해를 주었다. 따라서, 본 연구는 유목의 발생과 흐름에 따른 거동을 수치적으로 분석하여, 폭우나 쓰나미와 같은 거대흐름과 산지와 방풍림 등에서 발생하는 유목의 발생과 거동과정을 예측하고, 흐름과 유목 거동에 따른 피해지역을 선별할 수 있는 방법을 구축하기 위한 초기단계로서, 이를 위해 유목의 발생과정의 역학적 모델링을 수치모듈에 적용하였고 이를 활용하여 수치모의를 수행하였다. 흐름분석을 위해 쓰인 모형은 홍수범람 모형인 Nays2D Flood 이며 천수방정식을 기본으로 한다. 쓰나미의 흐름은 해안가의 방풍림지역을 상류단 경계조건으로 하여 발생 당시 관측된 수심변화를 본 모형의 상류단 경계조건으로 입력하였다. 상류단 경계조건에서 쓰나미의 유속은 수심에 따른 파속으로 계산하였다. 본 연구에서는 또한 유목의 발생과 흐름거동을 기존에 개발된 입자법 기반의 유목동역학모형을 활용하여 수치적으로 모델링 하였다. 유목은 유연성이 없는 원주형 강체로 가정하였고 초기설정으로는, 방풍림지역에 30만개의 유목이 하상의 수직방향으로 배치되어있는 것으로 가정하였다. 여기서, 본 연구에서는 쓰나미가 발생하면 흐름에 따른 항력으로 인해 수직방향으로 배치된 유목이 부러지며, 흐름과 함께 흘러가는 현상을 모델링하였다. 본 연구는 폭우나 쓰나미와 같은 거대흐름으로 인해 발생할 수 있는 유송잡물과 유목의 거동을 예측분석하는 기초연구자료로 활용될 수 있으며, 더 나아가 유목의 발생과정까지 수치적으로 재현하는 모델링을 수행하였기 추후에, 산지와 하천에서 발생할 수 있는 유송잡물의 발생과 연행 과정을 보다 세부적으로 예측할 수 있는 기초방법론으로 쓰일 수 있을 것으로 판단된다.

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An Analytical Study of the Effect of Inclined Angle of Road on Turn-over Accident of a High-speed Coach running on a Curved Road under Cross-wind Condition (횡풍이 작용하는 속도로의 회전구간에서 도로의 편경사각이 주행차량의 전복사고에 미치는 영향에 관한 분석연구)

  • Park, Hyeong-Su
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.373-381
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    • 2017
  • Kyeonggi Provincial Government is considering double decker bus service to solve the problem of heavy rush hour traffic. However, the height-to-width ratio is more than 1.16 times larger than that of a general high-speed single decker bus, and the center of gravity is higher. This could cause driving stability problems, such as turnover and breakaway from the lane, especially under strong side-wind conditions at high speed. In this numerical study, the driving characteristics of a model double decker bus were reviewed under side-wind and superelevation conditions at high driving speed. The rolling, pitching, and yawing moment of the model bus were calculated with CFD numerical simulation, and the results were compared to the recovery angular moments of the model bus to evaluate the dynamic stability under given driving conditions. As the model vehicle moves on a straight level road, it is stable under any side-wind conditions. However, on a curved road under side-wind conditions, it could reach unstable conditions dynamically. There is a chance that the bus will turn over when it moves on a curved road with a radius of gyration less than 100 m under side-wind (15 m/s). However, there is a very small chance of breakaway from the lane under any driving conditions.

Development Trend of Shock-Absorbing Landing gear for Lunar Lander (달착륙선 충격흡수 착륙장치 개발동향)

  • Kim, Won-Seock;Kim, Sun-Won;Hwang, Do-Soon
    • Current Industrial and Technological Trends in Aerospace
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    • v.9 no.1
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    • pp.119-129
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    • 2011
  • The soft landing of a lunar lander after the entrance of lunar orbit is an essential prerequisite for the accomplishment of the lander's lunar mission. During the landing process of a lunar lander, efficient shock absorption and stability maintenance are indispensible technology to protect payloads. Therefore, the landing gear is a crucial structural component of a lunar lander, it has to absorb the kinetic energy associated with touchdown and support the static load of the landing module in an upright position. In this paper, various landing gears of lunar landers which are being developed as well as which had been successfully landed on the moon surface are investigated. In the end, the Korean lunar lander, which is being designed for preliminary development model, is presented as an example of the lunar lander development.

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Studies on Korean Digital Fantasy Film -Genealogy, Case, and Social Meaning (한국 디지털 판타지 영화 연구 -계보, 표본, 그리고 사회적 의미)

  • Kim, Chung-Kang
    • Journal of Popular Narrative
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    • v.26 no.1
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    • pp.41-76
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    • 2020
  • Recently, the cinema industry faced a crisis on the rise of various media platforms such as Netflix, Amazon Prime, IPTV, and Kakao Page. The rate of film release in the theater has become ever shorter, and the secondary consumption of film through IPTV, tablet, PC, or mobile has seen a drastic increase. In the midst of this new media-geography, the most significant change in recent years would be the rise of the 'fantasy film' genre. This paper explores the conditions and characteristics of fantasy films in the way in which the genre has been constituted, and delves into particular aspects that its contents contain. This is an attempt to understand the sociology of the birth of a new genre. In this process, this paper will ask two frequently raised questions in regard to this genre. The first is to ask whether we can discern fantasy from reality, and the second is to examine whether the fantasy genre implicates certain social subversion. These two questions aim to discover how fantasy forms a relationship with reality and what this means. To do so, this paper will trace the genealogy of the fantasy film genre in Korea and analyze recent big hits such as the series as the model case of digital fantasy film. Through this exploration, this paper will be able to provide a new sociology of the fantasy film production and consumption in the 21st century Korea.

The Formal Innovation and Social Reflection of Korean Web Fiction Fantasy -Centered on 'Book Traveler' Genre (한국 웹소설 판타지의 형식적 갱신과 사회적 성찰 -책빙의물을 중심으로)

  • Yu, In-Hyeok
    • Journal of Popular Narrative
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    • v.26 no.1
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    • pp.77-102
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    • 2020
  • This article analyzes 'book traveler' stories as a new sub-genre of Korean fantasy web fiction. Formal innovation is revealed as the major motivation of Korean fantasy web fiction's narratives. Furthermore, the imagination of social resistance was presented as the formal devices of the genre. These theses were performed during the analysis of the two characteristics of the genre. In this genre, the main character is the writer or reader of fantasy stories. He moves into a novel he is describing or reading. The original novel, which was entered by the main character, is a space characterized by the custom of a typical fantasy genre. Therefore, the main character actually experiences cliché, typical genre devices and plots. The most important action for the main character here is to 'bend' the custom of the original. Therefore, this genre is in the form of the main motive being the refraction of typology. Meanwhile, the main character is not the central character of the original, but a secondary figure. The central character of the original book is usually from the ruling class, which monopolizes the good resources of society. At this time, the genre creates a subversive situation in which the social underdog goes beyond the social power through plots that overwhelm the central figure. It converts the reader's social desire into a genre device. To summarize, the latest trend in Korean web novel fantasy has captured scenes of renewed Korean genre literature practices. It sensitively reflects the social context of the contemporaries and the reader's desire. Thus, the Korean web novel fantasy has reflected both its internal conditions and its social context.

Lodging Mechanisms and Reducing Damage of Rice Plant (벼 도복 발생요인과 피해경감 대책)

  • Lee, Moon-Hee;Oh, Yun-Jin;Park, Rae-Kyeong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.36 no.5
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    • pp.383-393
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    • 1991
  • Lodging of rice plant is the most important damage by unfavourable weather conditions in rice cultivation. High levels of nitrogen application and growing of Japonica rice variety is one factor to increase the lodging damage. Lodging of rice plant decreasing grain yield; 34% at milky. 21% at dough. 20% at yellow stage. decreasing grain Quality. increasing green rice. and increasing labor cost to harvest. To decrease lodging damage. the lodging resistant varieties will be selected and cultural practices such as amount and time of nitrogen application. planting density. water management. and disease and pest control methods have to be study for the short and strong culm. and good rooting system. Also. application methods such amount and time of plant growth regulators and new types of chemicals will be develop for the reducing lodging of rice plant. To decrease the lodging damage in direct seeding cultivation. first identifying the differences of lodging mechanisms between hand transplanting and direct seeding, second establish the suitable direct seeding methods such as seedling establishement. fertilization. and water menagement.

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AN ELECTROMYOGRAPHIC STUDY ON THE CHANGES IN MUSCLE ACTIVITY IN DIFFERENT MALOCCLUSION TYPES FOLLOWING ACTIVATOR THERAPY (Activator 사용전후 부정교합 유형에 따른 각 근육 활성도의 변화에 관한 연구)

  • Lee, Jin-Woo;Cha, Kyung-Suk
    • The korean journal of orthodontics
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    • v.26 no.1 s.54
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    • pp.65-82
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    • 1996
  • This study was carried out to study the changing patterns in muscle activities in Angle's II and Class III malocclusion patients following activator therapy, To study the activities of anterior temporal(T.A.), masseter(M.M.), posterior temporal(T.P.), and anterior belly of digastric(D.A.) muscles, surface electrodes were placed on 15 Angle's Class II and 17 Angle's Class III malocclusion patients and following conclusions were obtained after electromyographic recordings were taken at prior to the activator therapy and at some time between 6 -12 month after the start of activator therapy. 1. Class II and Class III malocclusion groups, when compared to normal occlusiongroup, showed no significant differences during resting and swallowing. But significant differences were observed in masseter and posterior temporal muscles during clenching. 2. Most of the muscles studied showed a certain pattern, that is those groups whose pre-treatment E.M.G. were lower than the normal value showed significant increase after activator therapy, whereas those groups whose pre-treatment E.M.G. were higher than the normal value showed significant decrease after activator therapy. This pattern was observed in all of the muscle groups studied except T.A.(swallowing), T.P.(clenching) and D.A.(swallowing, clenching) in Angle's Class III malocclusion group and in Angle's Class II malocclusion group, above tendency were observed only in T.A.(swallowing), M.M.(resting, swallowing) and T.P.(clenching). This pattern was less obvious during clenching. 3. When E.M.G. activity after activator therapy between Angle's Class II and Class III malocclusion group was compared, Class III malocclusion group showed more increase during resting, and Class II malocclusion group showed more increase during swallowing and clenching excepting M.M. and D.A. respectively.

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