• Title/Summary/Keyword: Irregular Shaped

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Prognosis of aerodynamic coefficients of butterfly plan shaped tall building by surrogate modelling

  • Sanyal, Prasenjit;Banerjee, Sayantan;Dalui, Sujit Kumar
    • Wind and Structures
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    • v.34 no.4
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    • pp.321-334
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    • 2022
  • Irregularity in plan shape is very common for any type of building as it enhances better air ventilation for the inhabitants. Systematic opening at the middle of the facades makes the appearance of the building plan as a butterfly one. The primary focus of this study is to forecast the force, moment and torsional coefficient of a butterfly plan shaped tall building. Initially, Computational Fluid Dynamics (CFD) study is done on the building model based on Reynolds averaged Navier Stokes (RANS) k-epsilon turbulence model. Fifty random cases of irregularity and angle of attack (AOA) are selected, and the results from these cases are utilised for developing the surrogate models. Parametric equations are predicted for all these aerodynamic coefficients, and the training of these outcomes are also done for developing Artificial Neural Networks (ANN). After achieving the target acceptance criteria, the observed results are compared with the primary CFD data. Both parametric equations and ANN matched very well with the obtained data. The results are further utilised for discussing the effects of irregularity on the most critical wind condition.

Development of 2.5D Electron Dose Calculation Algorithm (2.5D 전자선 선량계산 알고리즘 개발)

  • 조병철;고영은;오도훈;배훈식
    • Progress in Medical Physics
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    • v.10 no.3
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    • pp.133-140
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    • 1999
  • In this paper, as a preliminary study for developing a full 3D electron dose calculation algorithm, We developed 2.5D electron dose calculation algorithm by extending 2D pencil-beam model to consider three dimensional geometry such as air-gap and obliquity appropriately. The dose calculation algorithm was implemented using the IDL5.2(Research Systems Inc., USA), For calculation of the Hogstrom's pencil-beam algorithm, the measured data of the central-axis depth-dose for 12 MeV(Siemens M6740) and the linear stopping power and the linear scattering power of water and air from ICRU report 35 was used. To evaluate the accuracy of the implemented program, we compared the calculated dose distribution with the film measurements in the three situations; the normal incident beam, the 45$^{\circ}$ oblique incident beam, and the beam incident on the pit-shaped phantom. As results, about 120 seconds had been required on the PC (Pentium III 450MHz) to calculate dose distribution of a single beam. It needs some optimizing methods to speed up the dose calculation. For the accuracy of dose calculation, in the case of the normal incident beam of the regular and irregular shaped field, at the rapid dose gradient region of penumbra, the errors were within $\pm$3 mm and the dose profiles were agreed within 5%. However, the discrepancy between the calculation and the measurement were about 10% for the oblique incident beam and the beam incident on the pit-shaped phantom. In conclusions, we expended 2D pencil-beam algorithm to take into account the three dimensional geometry of the patient. And also, as well as the dose calculation of irregular field, the irregular shaped body contour and the air-gap could be considered appropriately in the implemented program. In the near future, the more accurate algorithm will be implemented considering inhomogeneity correction using CT, and at that time, the program can be used as a tool for educational and research purpose. This study was supported by a grant (#HMP-98-G-1-016) of the HAN(Highly Advanced National) Project, Ministry of Health & Welfare, R.O.K.

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Heterobothrium Infection of Tiger puffer, Takifugu rubripes Cultured in Ponds on Land (양식 자주복 (Takifugu rubripes)의 Heterobothrium 감염증)

  • Park, Sung-Woo;Park, Gi-Chun
    • Journal of fish pathology
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    • v.19 no.2
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    • pp.99-108
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    • 2006
  • Diseased tiger puffer (Takijugu rubripes) showed anorexia and severe anemia in the gills. In wet mount preparations Heterobothrium sp. with 4 sets of clamps on the opisthohaptor attached to the gill filaments of the diseased fish. From the drum-shaped filter for filtration of the culturing water and the sediment of aquarium held the diseased fish in the laboratory, their eggs forming long strings through connection of the bipolar filaments could be easily collected. The parasites with 4 pairs of clamps on the opisthohaptor were 2.38mm in length and 0.71 mm in width, but had no isthmus which was separated the opisthohapor from the body proper. The parasites could be easily distinguished from Heterobothrium tetrodonis and H. okamotoi in the absence of distinct isthmus, and resembled H. yamagutii described from the gills of Takifugu xanthopterus in Japan. Their eggs were yellowish spindle in shape and 180-200 x 5-6 Iffil in size, which were pointed at both ends. The eggs were linked to adjacent egg shells like a string of beads by the filaments. Onchomiracidia, ciliated larvae spawned from the eggs were 133 Iffil (120-146 Iffil) x 751ffil (68-80 Iffil) in size. The length of the ciliates was 12 Iffil in the anterior part of the larvae and 14 Iffil in the posterior part. Round or leaf-shaped young parasites attached on the secondary gill lamellae. There was a tendency that most of round smaller parasites without an opisthohaptor were found in the middle part of the gill lamellae while leaf-shaped larger ones with a opisthohaptor attached on the distal part of the gill filaments. Each clamp of mature parasites grasped one secondary gill filament which resulted in bending of the filaments and hyperplasia of the epithelium and mucous cells. In the branchial cavity around the pseudobranch, mature parasites grasped the adjacent ones by means of the clamps, and the epithelia of the branchial cavity around the parasites showed severe irregular hyperplasia and erosion with strongly PAS-positive mucous cells.

Synthesis of Spindle Shape α-FeOOH Nanoparticle from Ferrous(II) Sulfate Salt (황산 제1철을 이용한 방추형 괴타이트 나노 입자의 합성)

  • Han, Yang-Su;You, Hee-Joun;Moon, Ji-Woong;Oh, You-Keun
    • Journal of the Korean Ceramic Society
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    • v.42 no.11 s.282
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    • pp.722-728
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    • 2005
  • A wet-chemical route was utilized to obtain nanosized crystalline goethite ($\alpha$-FeOOH) particle, which was known as an oxidation catalyst in reducing carbon monoxide (CO) and dioxine during incineration. A cost-effective $FeSO_4{\cdot}7H_2O$ was used as starting raw material and a successive process of hydrolysis-oxidation was utilized as synthetic method. The effects of the initial $Fe^{2+}$ concentration, hydrolysis time and oxidation period on the crystalline phase and particle characteristics were systematically investigated by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and BET analyses. It was found that the spindle-shaped crystalline $\alpha$-FeOOH particle with the width of 70 nm and the length of 200 nm could be obtained successfully when the initial concentration of 1.5 M, hydrolysis time of 4h, and oxidation period of 10 h, respectively. In addition, it was observed that the spindle-shaped $\alpha$-FeOOH particle consisted of nano-sized primary crystallites of $30\~50\;nm$, which were de-agglomerated into individual particle and successively re­agglomerated into spherical or irregular-shaped agglomerates beyond certain periods in the hydrolysis and oxidation process.

Thermal and Mineralogical Characterization of Ca-montmorillonite from Gampo Area: Morphology by Electron Microscope Study (감포지역(甘浦地域) Ca-몬모릴로나이트의 광물학적(鑛物學的) 및 열적특성(熱的特性) : 전자현미경(電子顯微鏡)에 의한 형태적(形態的) 연구)

  • Moon, Hi-Soo;Choi, Sun Kyung
    • Journal of the Mineralogical Society of Korea
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    • v.1 no.2
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    • pp.117-130
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    • 1988
  • The morphology of the Ca-montmorillonites from the Gampo area was investigated by the use of scanning and transmission electron microscope. These bulk samples show an irregular or rugged surface with well developed cavities and relict outline of original ash material at low magnification by SEM, indicating that montmorillonites are derived from volcanogenic material. Two different types of morphology of montmorillonites by SEM were observed which appear to depend very much on the space available for crystal growth. One is honeycomb structure montmorillonite growing in an open space. The other is the closely packed aggregates of intergrown montmorillonite showing platy particles where available space for the growth is limited. Several different habits of montmorillonite within a single sample can be observed by TEM. The dominant habit observed is the irregularly shaped and foliated aggregates and the platy shaped particles. In general, platy shaped particles are relatively abundant in the samples from Yongdongri compared with those from Jugjeonri area.

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A Study on the Formations of Thermal Stratification of Furniture Fire (가구화재시 열적성층의 형성에 관한 연구)

  • 허만성
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1996.11a
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    • pp.24-29
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    • 1996
  • The objective of this research is to study on the formations of thermal stratification in a room in case of several furniture fires such as trashcan, chair, carpet, sofa, mattress and wardrobe as a fire starter in a residential room by performing the experimental studies. The uniformly distributed fire in case of carpet showed that the ignition and the initial growth period were relatively short while the fully developed period was considerably long. The concentrated fires such as the mattress and wardrobe showed that the ignitions and the initial growth periods were relatively long. When fire spread to only one direction, like the case for the trashcan with a regular shape, there was one peak of temperature profile, and for the irregular shaped furniture such as chair, sofa, mattress and wardrobe, there were two or more peaks. The interface heights for the furniture fires were around 1(m) mataining constant state. However, at the time of the maximum temperature, the interface height was lowered to 0.25(m)-0.75(m) from the floor

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Digital Technologies for Structural System Design of Irregular Shaped Buildings (비정형 건축물 구조시스템 설계를 위한 디지털 요소기술)

  • Lee, Jae-Cheol
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2009.04a
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    • pp.76-79
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    • 2009
  • 최근 계획되고 있는 초고층 건축물은 높이에 따른 기술경쟁력의 과시와 함께 비정형의 자유로운 건축적 형상을 통한 디자인 형태의 상징성을 강조하는 경향을 보이고 있다. 이러한 비정형 건축물의 구조시스템은 기술적, 경제적 문제로 인해 한정된 수의 가능성 있는 대안만이 고려되어 왔으나, 첨단 디지털 기술의 발전에 따라 비정형 건축물의 구조시스템에 대해 이전에는 적용이 불가능하였던 다수의 구조시스템 대안을 생성하고 동일한 컨셉을 가진 다양한 구조시스템 대안의 비교평가를 통해 검토안의 수를 최소화하는 것이 가능해졌다. 본 연구에서는 비정형 건축물 구조시스템 설계를 위한 디지털 요소기술에 대해 현재까지의 연구현황을 분석하고 앞으로의 연구방향과 과제를 제시하고자 한다.

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Leiomyoma in the Esophagus (Report of A Case) (식도(食道) 평활근종(平滑筋腫)의 수술치험(手術治驗) 1례(例))

  • Oh, Chul Soo;Kim, Kun Ho
    • Journal of Chest Surgery
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    • v.9 no.2
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    • pp.311-314
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    • 1976
  • This is a report of leiomyoma in the esophagus. patient had suffered from mild intermittent dysphagia on eating without any other complaints. This complaint had been going for 45 days, but was not progressed. The esophagogram revealed an ovoid walnut-sized smooth filling defect in the midportion of the esophagus. The mucosal folds of the esophagus were not destroyed. A benign intramural tumor of the esophagus, such as leiomyoma, was suspected with X-ray finding and clinical features. On Aug. 13, 1976 a thoracotomy was performed at right 4th intercostal space. A firm, irregular shaped mass in the wall of the esophagus was enucleated by blunt dissection without any injury of the mucosa of the esophagus. The diagnosis of leiomyoma was confirmed with histopathological finding. Postoperative course was uneventful.

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A Study on the Diversification Trend of Apartment Interior Space Planning (아파트 실내공간의 차별화 경향에 관한 연구)

  • 오혜경;신지원
    • Korean Institute of Interior Design Journal
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    • no.15
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    • pp.31-38
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    • 1998
  • The purpose of this study was to analyze the tendency of the current diversified apartment planning. This study was examined by 13 newspapers from January 1th 1995 to 30th 1997. The major findings in this study were summarized as follows: 1. The strategy of major apartment construction co. was diversified into space planning interior image facilities and utilities and outdoor space design. 2. The trend of space planning was diversified into apartment for 3 generation apartment with its own inside gardeen apartment with kitchen facing south multi-story apartment, apartment with round shape room irregular shaped apartment 3. The trend of interior image was diversified into Korean style natural style casual elegantstyle modern style and classical style.

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Leiomyoma of the Esophagus -A Case Report- (식도의 평활근종 -수술치험 1례 보고-)

  • Kim, Byeong-Hwan;Jang, Un-Ha
    • Journal of Chest Surgery
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    • v.28 no.5
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    • pp.521-524
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    • 1995
  • Esophageal leiomyoma is a very rare disease. We present a patient who underwent enucleation of esophageal leiomyoma through a left thoracotomy. The patient was suffered from substernal pain and chest discomfort for 4 months.The esophagogram revealed irregular ovoid smooth filling defect in just proximal portion of G-E junction with the normal mucosal folds. Chest CT demonstrated well-defined, polypoid tumor mass on the anterolateral wall of the distal esophagus. Esophagoscopy revealed normal intact mucosal patterns with swollen hard protruded tumor mass lesion from the just proximal portion of G-E junction. In June, 1993, patient underwent enucleation of esophageal leiomyoma through the left thoracotomy. A horseshoe and spiral shaped, whitish firm tumor mass was noted on the distal esophagus, and the tumor mass was enucleated by blunt dissection carefully. The esophageal leiomyoma was confirmed with histopathological examination. The postoperative course was smooth and uneventful.

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