• Title/Summary/Keyword: Wall following

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PREDICTION OF FREE SURFACE FLOW ON CONTAINMENT FLOOR USING A SHALLOW WATER EQUATION SOLVER

  • Bang, Young-Seok;Lee, Gil-Soo;Huh, Byung-Gil;Oh, Deog-Yeon;Woo, Sweng-Woong
    • Nuclear Engineering and Technology
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    • v.41 no.8
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    • pp.1045-1052
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    • 2009
  • A calculation model is developed to predict the transient free surface flow on the containment floor following a loss-of-coolant accident (LOCA) of pressurized water reactors (PWR) for the use of debris transport evaluation. The model solves the two-dimensional Shallow Water Equation (SWE) using a finite volume method (FVM) with unstructured triangular meshes. The numerical scheme is based on a fully explicit predictor-corrector method to achieve a fast-running capability and numerical accuracy. The Harten-Lax-van Leer (HLL) scheme is used to reserve a shock-capturing capability in determining the convective flux term at the cell interface where the dry-to-wet changing proceeds. An experiment simulating a sudden break of a water reservoir with L-shape open channel is calculated for validation of the present model. It is shown that the present model agrees well with the experiment data, thus it can be justified for the free surface flow with accuracy. From the calculation of flow field over the simplified containment floor of APR1400, the important phenomena of free surface flow including propagations and interactions of waves generated by local water level distribution and reflection with a solid wall are found and the transient flow rates entering the Holdup Volume Tank (HVT) are obtained within a practical computational resource.

A Study on the Community Space for Socialization of Secondary School Students - Focused on Alternative Educational Perspective Using Examples of Schools from Other Countries - (중등학교 학생의 사회성 확대를 위한 커뮤니티 공간에 관한 연구 - 대안교육 관점의 해외학교 사례 분석을 중심으로 -)

  • Lee, Jae-Rim
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.12 no.2
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    • pp.43-52
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    • 2013
  • This study aims to theoretically examine the educational and living elements that are needed for social education in the school system and suggest an approach to apply this result to the environmental aspects of the space in schools. To do this, characteristics of space in exemplary middle school oversee were analyzed. Also, the characteristics and status of the school space environment that foster socialization were examined. In order to increase students' social skills, the following community space should be considered. 1) teaching and learning spaces facilitating a variety of teaching methods, such as lecture, discussion, seminar classes, 2) open-spaces for communication among students, such as home base, hall, library, museum, and restaurant, 3) open-spaces for STEM education, 4) transparent windows located in the boundary wall between classrooms and hallways, 5) a large performance stage for presentation of student activities and experiences, 6) smart-learning spaces for fluent ICT system in classes and in public spaces, 7) restaurants and libraries located in the middle space of the school, and 8) ecological environments for student learning.

Performance-based Design of 300 m Vertical City "ABENO HARUKAS"

  • Hirakawa, Kiyoaki;Saburi, Kazuhiro;Kushima, Souichirou;Kojima, Kazutaka
    • International Journal of High-Rise Buildings
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    • v.3 no.1
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    • pp.35-48
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    • 2014
  • In designing a 300 meter high skyscraper expected to be the tallest building in Japan, an earthquake-ridden country, we launched on the full-scale performance based design to ensure redundancy and establish new specifications using below new techniques. The following new techniques are applied because the existing techniques/materials are not enough to meet the established design criteria for the large-scale, irregularly-shaped building, and earth-conscious material saving and construction streamlining for reconstructing a station building are also required: ${\bullet}$ High strength materials: Concrete filled steel tube ("CFT") columns made of high-strength concrete and steels; ${\bullet}$ New joint system: Combination of outer diaphragm and aluminium spray jointing; ${\bullet}$ Various dampers including corrugated steel-plate walls, rotational friction dampers, oil dampers, and inverted-pendulum adaptive tuned mass damper (ATMD): Installed as appropriate; and ${\bullet}$ Foundation system: Piled raft foundation, soil cement earth-retaining wall construction, and beer bottle shaped high-strength CFT piles.

Characteristics of Ibasho by The Elderly in Exterior Space of Housing Complex - Focusing on Toyoshikidai Housing Complex in Kashiwa city of Chiba Prefecture, Japan - (집합주택단지의 옥외공간에 있어서 고령자 이바쇼(居場所)의 특징고찰 - 일본 치바현(千葉縣)의 카시와시(柏市) 토요시키다이(豊四季台)단지를 대상으로 -)

  • Lee, Yunjeong;Byun, Kyeonghwa;Yoo, Changgeun
    • Journal of the Korean housing association
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    • v.26 no.6
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    • pp.83-92
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    • 2015
  • The purpose of this study is to analyze the characteristics of exterior spaces used by the elderly of housing complex. The exterior spaces are used for going out in everyday life with the view point that the elderly have to go out from the inside home in order to prevent isolating the elderly from local community. For that Toyoshikidai housing complex in Kashiwa city of Chiba prefecture, Japan is selected and carried out questionnaire survey and field survey targeting residents. The results are following as. For spatial characteristics, the location installed benches, location occupied in one part by roof, wall, or plants, place connecting to moving flow of the aged, and an open expanse getting safety from vehicle are taken advantages for the elderly. For using benches, the elderly of 70.1% do not have experience using benches installed in all those places. The the biggest reason is that they are not tired. However, 36.8% of the elderly are using benches in order to take a rest and 20.8% of them are using benches in order to talk with the other people. Bench is ibasho of the elderly.

Clinical Experience of Three-dimensional Reconstruction Using Free TRAM Flap after Total Maxillectomy with Orbital Exenteration (상악골 전절제술 및 안와내용물 적출술 후 횡복직근 유리피판을 이용한 3차원적 재건에 대한 치험례)

  • Lee, Seung Ryul;Woo, Jong Seol
    • Archives of Craniofacial Surgery
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    • v.10 no.1
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    • pp.40-43
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    • 2009
  • Purpose: Extensive midface defect following total maxillectomy with orbital exenteration and cheek skin resection should be three dimensionally reconstructed with a large flap that have a sufficient volume of tissue and multiple skin islands. We describe our transverse rectus abdominis myocutaneous(TRAM) free flap with three skin islands which was successfully used in this situation. Methods: A 58-year-old man was performed enbloc total maxillectomy including orbital contents and wide cheek skin because of invasive maxillary squamous cell carcinoma. He was immediately reconstructed with TRAM flap that was designed not vertical but transverse fashion for providing sufficient skin area. Also, deepithelialization procedure making for multiple skin islands was done in flap insetting period when appropriate modification according to the intraoperative situation was possible. Dead space was completely obliterated by bulky muscular tissue, and three skin islands were used for lining of lateral nasal wall, palatal surface, and cheek skin restoration. Results: Postoperative course was satisfying. Maintaining of proper ipsilateral nasal airway, loss of rhinolalia and oronasal regurgitation of food particles, and restoration of cheek contour were successfully obtained. Conclusion: We report clinical experience of threedimensional reconstruction using free TRAM flap after total maxillectomy with orbital exenteration.

Eyeball deviation by orbital mucocele after midface sinus injury

  • Oh, Se Young;Choi, Ji Seon;Lim, Jin Soo;Kim, Min Cheol
    • Archives of Craniofacial Surgery
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    • v.21 no.1
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    • pp.53-57
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    • 2020
  • A mucocele is an epithelium-lined, mucus-filled cavity in the paranasal sinuses. Mucocele may develop due to scarring and obstruction of the sinus ostium caused by midface sinus trauma, such as orbital bone fracture or endoscopic sinus surgery. The authors report two cases of orbital mucocele as complications following midface sinus injury (endoscopic sinus surgery in one case, and orbital fracture repair in the other). In both cases, imaging studies showed a large orbital mucocele accompanied by bony erosion and orbital wall remodeling, compressing the ocular muscle. Using an open approach, the lesion was excised and marsupialized. The symptoms resolved, and the postoperative eyeball position was normal. Orbital mucocele may cause serious complications such as ocular symptoms, orbital cellulitis, osteomyelitis, and the formation of an abscess with the potential to invade the brain. Therefore, surgeons should consider the possibility of mucocele as a late complication of surgery and initiate an immediate work-up and surgical treatment if needed.

Development and Quality of Dried Cherry-Tomatoes (건조방울토마토 제조와 품질 특성)

  • 윤경영;김미현;이광희;신승렬
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.6
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    • pp.1283-1287
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    • 1999
  • This study was carried out to develop new processed food from cherry tomatoes. The dried cherry tomatoes were prepared by using a sequence of osmotic dehydration, air drying, vacuum drying and freeze drying. The moisture contents of dried cherry tomato products by nontreatment and osmosis treatment were about 11~13% and 7.5~ 10%, respectively. The vitamin C contents of the dried product after osmotic dehydration were higher than those of the dried products by nontreatment. The vitamin C content of the freezing dried product was the highest of the others. The vacuum dried product by nontreatment was retained color of fresh fruit in the change of color. The ΔE value of the air dried product was lower than those of the others. As a result to microscopic analysis, fresh cherry tomato was observed regular tissue, while cherry tomato treated by osmosis was observed a cell collapse following the loss of water. The dried product had cell shrinkage and dense tissue. And the cell wall of dried products after osmotic dehydration were much more damage than those of nontreatment dried product. The palatability of the air dried product was the best of three drying methods. The dried cherry tomatoes treated by osmosis were superior to the dried cherry tomatoes by nontreatment.

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Cell Division in the Absence of Mitosis: The Unusual Case of the Fucoid Ascophyllum nodosum (L.) Le Jolis (Phaeophyceae)

  • Garbary, David J.;Lawson, Greg;Clement, Kelly;Galway, Moira E.
    • ALGAE
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    • v.24 no.4
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    • pp.239-248
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    • 2009
  • Fluorescence and electron microscopy were used to examine epidermal shedding in the fucoid alga, Ascophyllum nodosum. Mature meristoderm cells are ca. 50-100 x 30-40 ${\mu}m$ and highly polarized, with a single nucleus and chloroplasts near the base of the cell. Nuclei in these cells undergo mitosis when they are dividing to form a new cortical cell towards the middle of the frond, or anticlinal divisions as part of frond elongation. However, cytokinesis also occurs regularly in these cells when a new periclinal wall is deposited at about 30% of the cell length from the apical end. The newly formed distal cells are anucleate and without chloroplasts. Following cytokinesis the tangential walls then break at the thinnest point. The whole process is synchronous in adjoining epidermal cells across large areas of the frond surface, and this layer dehisces from the thallus. This is the only known plant or algal system in which cytokinesis regularly occurs in the absence of mitosis. We consider this process a novel form of programmed cell death.

Determination of empirical formula for instantaneous heat transfer coefficients in a S. I. engine (스파크 점화기관의 순간열전달계수의 경험식 결정)

  • Han, Seong-Bin;Gwon, Yeong-Jik;Lee, Jeong-Yeol
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.11
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    • pp.1475-1484
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    • 1997
  • A new empirical formula for instantaneous heat transfer coefficients was determined. The determination of this formula is in need for prediction of instantaneous value of heat transfer coefficients to analyze in more detail the time variation of heat transfer rate from gas to wall in combustion chamber of a spark ignition engine. As the result, following formula was determined. h=687 $p^{0.75}$ $U^{0.75}$ $D^{0.25}$ - $T^{-0.465}$ U(.theta.)=O.494 $V_{p}$ +0.73*10$^{6}$ (1.35 p dV/d.theta.+V dp/d.theta.) Using this empirical formula, the instantaneous heat transfer coefficients of gas in the combustion chamber of spark ignition engine was predicted and compared with experimental values.

Effect of Sugar-Beet Pulp Supplementation on Fiber Degradation of Grass Hay in the Rumen of Goats

  • Masuda, Y.;Kondo, S.;Shimojo, M.;Goto, I.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.2
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    • pp.186-188
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    • 1999
  • This study was conducted to investigate the effects of four levels (0, 10, 20, 40 %) of sugar-beet pulp (SB pulp) supplementation to Italian ryegrass hay (IRG hay) on the fiber degradability of IRG hay in the rumen of goats. The following results were obtained: Degradabilities of DM, NDF, ADF and hemicellulose of IRG hay in the rumen increased significantly (p<0.05) by 10 % level supplementation of SB pulp to IRG hay. This was probably due to the increased numbers (p<0.05) of total viable bacteria, pectin-fermenting, xylan-fermenting and cellulolytic bacteria in the rumen in the increased supply of degradable pectic substances and hemicellulose at 10% level supplementation of SB pulp pectin. In 40% supplementation of SB pulp, ruminal pH was lowered by the fermentation of increased amount of molasses from SB pulp, resulting in the depression of growth of fiber fermenting bacteria and hence the decrease in degradabilities of cell wall fractions. It was suggested from this study that the sugar-beet pulp supplementation to forages at the level of 10% in the total diet increased fiber degradation of forage in the rumen of goats.