• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.947-964
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• 2014

Rubble mound breakwaters protect the coastal line against severe erosion caused by wave action. This study examined the performance of different sizes and properties (i.e. height of vertical wall and tetrapod size) of rubble mound breakwaters on reducing the overtopping discharge. The physical model used in this study was derived based on an actual rubble mound in Busan Yacht Harbor. This research attempts to fill the gap in practical knowledge on the combined effect of the armor roughness and vertical wall on wave overtopping in rubble mound breakwaters. The main governing parameters used in this study were the vertical wall height, variation of the tetrapod weights, initial water level elevation, and the volume of overtopping under constant wave properties. The experimental results showed that the roughness factor differed according to the tetrapod size. Furthermore, the overtopping discharge with no vertical wall was similar to that with relatively short vertical walls (${\gamma}_v=1$). Therefore, the experimental results highlight the importance of the height of the vertical wall in reducing overtopping discharge. Moreover, a large tetrapod size may allow coastal engineers to choose a shorter vertical wall to save cost, while obtaining better performance.

• Korean Institute of Interior Design Journal
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• v.19 no.3
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• pp.86-94
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• 2010

Art-Wall is the term for a surface wall representing artistic expression by using different materials or images in interior spaces. Usually this is the focal point in an interior space and sometimes it called as an image wall. In the new millenium Art-walls began to use in living spaces. While in the early stages of the development, Art-Wall was limited in a living room, in contemporary it spread into overall living spaces using various patterns and materials. Therefore, the research on Art-Walls in contemporary living spaces is essential to understand this development. The purpose of this study is to find out characteristics of patterns on Art-Walls as an imagery element in contemporary interior spaces. To analyze the characteristic, the analysis table for Art-Walls are constructed based on classifications of wallpapers and textiles. Based on this analysis table, 89 examples of Art-Walls from four major periodicals from 2008 to 2009 were examined. As a result of the analysis, in contemporary interior spaces solid-texture pattern is most frequently appeared. Then natural motifs are the next most popular using oversized or irregular layouts. The result shows that naturalistic expression is significant in interior space in 2008 to 2009. Therefore, Art-Walls that adapted diverse patterns are an essential element in contemporary interiors to represent the major concept of the space.

• Wind and Structures
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• v.12 no.2
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• pp.89-101
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• 2009

The Monte Carlo procedure was used to simulate wind load effects on a light-frame low-rise structure of irregular shape and a main wind force resisting system. Two analytical models were studied: rigid-beam and rigid-plate models. The models assumed that roof diaphragms were rigid beam or rigid plate and shear walls controlled system behavior and failure. The parameters defining wall stiffness, including imperfections, were random and included wall stiffness, wall capacity and yield displacements. The effect of openings was included in the simulation via a set of discrete multipliers with uniform distribution. One and two-story buildings were analyzed and the models can be expanded into multiple-floor structures provided that the assumptions made in this paper are not violated.

• Journal of Plant Biology
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• v.5 no.2
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• pp.1-5
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• 1962

Attempts were made in order to make clear the meiotic irregularities, male gametophyte formation and spermatogenesis for the purpose of applying these embryological facts to taxonomic works. Followings are the results obtained : 1. Meiosis is extremely irregular, giving rise to giant, micro, and empty, pollens. Meiotic division in each PMC is observed synchronizing. 2. In the microspore immediately before the vegetative-generative nuclear division, the nucleus locates appressed to the inner wall, most of the other part of the cell being occupied by large vacuoles. 3. Spindle symmetry in the microspore nuclear division is of intermediate type. 4. Nuclear divisions in each micropore are not synchronized as in meiosis. 5. Generative nucleus is located in close contact with the inner wall, while the vegetative nucleus occupies the central part of pollen grain. The pollen in this stage looks somewhat like broad bean. Afterward the generative nucleus loses contact with the wall, the nuclear shape changing from lenticular to roundsh. 6. The generative nucleus in fully matured pollen grain usually takes the shape of crescence, those in abortive pollen, lenticular or ellipsoidal, etc.

• Journal of the Korean Home Economics Association
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• v.38 no.11
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• pp.137-149
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• 2000

The Purpose of this study was to investigate actual condition about the modem adaptation of interior elements(floor, wall, ceiling, door & window) in traditional thatched roof house. The examined objects were interior space of 36 restaurants and cafes in Seoul and Kyung-Ki Do area. 1. Floor: Jang-pan was mostly alternated with linoleum which huts Jang-pan pattem. Wumul-maru was adapted from the original and Jang-maru was alternated with wood or linolium which has western state Jang-maru pattern. Mud was adapted from the original or alternated with slate stone or rough finish cement. 2. Wall: Rice proper was alternated with rice paper book witch has chinese character, paper for parcels or modem wall paper. Plaster-white paint or white handy coat. Mud-mud color paint or bamboo stick witch located in the mud wall orginal. Log-half cut log. Wooden board-without cross bar or irregular form. 3. Ceiling: Yondung-Chongang was mostly adapted from the original and Banja-Chonjang was alternated with rice paper book which has Chinese character or modem wall paper. 4. Door and Window: Ttisal-mun and Panjang-mun were adapted from the original. Wan and A’character door and window were simplified character itself.

• Advances in pediatric surgery
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• v.7 no.1
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• pp.59-63
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• 2001

The authors, over the last 6 months, have treated 2 patients with perforated typhlitis complicating acute lymphocytic leukemia (ALL) with good outcome. The first patient was a 13-year-old male who developed intermittent high fever, abdominal pain, abdominal distention and diarrhea during the course of maintenance chemotherapy. The peripheral leukocyte ranged from 230-470/$mm^3$. Serial ultra sonograms and CT scans demonstrated irregular thickening of the cecal and ascending colonic walls and subsequent ragged perforation of the posterior wall of the cecum. He survived after treatment by right hemicolectomy and aggressive supportive measures. The patient case was a 3 year-old female who developed intermittent high fever, right lower abdominal pain, a mass, and watery diarrhea during the course of maintenance chemotherapy. Serial ultra sonograms and CT scans demonstrated irregular thickening of the cecal wall (6-15mm in thickness) and subsequent small perforation of the posterior wall of the cecum with thick-walled localized abscess. She has recovered completely after aggressive medical management. We learned two lessons from our experience treating these patients:1) early diagnosis provided by a high index of suspicion and the use of ultra sonogram or CT scan is essential. And 2) although perforation is one of the surgical indications for the treatment of typhlitis, it is possible to manage the perforation nonoperatively in selected cases with localized abscess.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.4_2
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• pp.637-644
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• 2022

In this study, the flow characteristics according to the shape of the vortex nozzle was studied by numerical analysis and the amount of microbubble generation was measured experimentally. The shape of the vortex nozzle is cylindrical, diffuser, and conical type. The axial fluid velocity in the induced tube gradually increased from the inlet to the outlet. In particular, the fluid velocity in the nozzle part increased rapidly. The velocity distribution of the fluid at the inlet of the induced tube showed that the flow rotates counterclockwise in the outer region and the inner center of the induced tube. At the outlet of the induced tube, the cylindrical and conical type showed rotational flow, and the diffuser type showed irregular turbulent flow. The dimensionless pressure ratio 𝜂 of the inner region of the induced tube was lower than that of the outer region. Also, 𝜂 near the outlet of the induced tube in cylindrical and conical type showed a similar tendency to the inlet area. At the outer region of inlet of induced tube, intense vorticity was observed on the wall and in lower region. At the inner region of inlet of induced tube, intense vorticity was observed on the inner wall of the induced tube and in the central region of the inlet of the induced tube. At the outlet of induced tube, in the case of the cylindrical and conical type, intense vorticity was observed near the inner wall, the diffuser type showed irregular strong vorticity inside the tube. The total number of bubbles measured was the most in the cylindrical type, and the microbubbles less than 50mm occurred the most in the conical type.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.36 no.1
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• pp.1-10
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• 2024

As increasing demands for a floating structure expanded from offshore industry facilities to living facilities, it has emerged that necessity of techniques to reduce motions of a floating structure. This study present a floating structure with porosity on the outer surface of the floater. Under each regular and irregular wave, responses of the floater was investigated in frequency domain. The proposed structure is composed of inner and outer floaters, which are connected to each other and the outer wall is perforated, and the heave and the pitch of floaters with different perforation rates (0~30%) were compared with at both the center and the edge. The results showed that pitch responses can be decreased by increasing of perforation rate of the floater. Comparing with responses of the non-perforated floater, those of the proposed floating structure were reduced to above 10% and 2%, respectively for regular and irregular wave conditions.

• Journal of the Society of Naval Architects of Korea
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• v.31 no.4
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• pp.73-81
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• 1994

The source and source/dipole distribution methods using 3-dimensional panel method have been widely used for ship motion analysis. When these methods are used, large errors in the predicted hydrodynamic coefficients are introduced around the irregular frequencies caused by the resonance of imaginary internal flow. Therefore, the irregular frequencies need to be removed for an accurate prediction of ship motion. This paper adopts 3-dimensional translating and oscillating Green function derived by Wu. The adaptive integration method, stretching transform and stationary phase method are used for the calculation of the calculation of Green function and the integral equation is derived by distributing the Green function n ship surface and inner free-surface. The condition of zero normal velocity, that is, wall condition on inner free-surface has been successfully used for the removal of irregular frequencies in oscillating problems. The calculations are carried out for series 60($C_B=0.7$) vessel and the results are compared with those of other theoretical analyses and experiment.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.6
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• pp.586-595
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• 2007

The analytic solution of wave scattering of monochromatic waves on a pile breakwater by an eigenfunction expansion method is extended to the case of directional irregular waves. The scattering wave spectrum and the force spectrum can be expressed from the reflection coefficient, transmission coefficient and the wave forces obtained from changing frequencies and incident angles in monochromatic waves. By numerical integration of 2-dimensional spectrum which is function of frequencies and incident angles, the representative values for the scattered waves and wave forces are obtained and the dependence of the transmission coefficients and wave forces on the directional distribution function, the principal wave direction, the submergence depth, and porosity is analyzed.