• Title/Summary/Keyword: shape formation

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A Study of Primiparous Womens Breastfeeding Experience (초산모의 모유수유 경험)

  • 김신정;양숙자
    • Journal of Korean Academy of Nursing
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    • v.27 no.3
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    • pp.477-488
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    • 1997
  • The purpose of this study was to understand the subjective breastfeeding experience of primiparous women to identify how breastfeeding was started and to explore the process of breastfeeding. The Grounded theory methodology was used. Data was collected from 6 primiparous women who had breastfed their infants for at least over 8weeks, recently breastfeeding or having breatfed their infants within the last 6 months. With the permission of the subjects, the interviews were recorded and transcribed. The data were analysed in the framework of grounded theory method as mapped out by Strauss and Corbin(1990). 105 concepts and 21 subcategories were confirmed in the analysis. In the process of data analysis, "Identity as a mother" was found to be the core phenomenon. The 21 sub-categories were as follows : natural food, neighbour inducement, self purpose, good feeling, tenderness, breast pain, change of breast shape, physical discomfort, loss of physical energy, confirmation of maternal role, formation of affection feeling of adhesion, one body through coupling, tie, capacity, role performance, mental comfort, healthy mother, healthy infant, confidence of breast milk, feeling of satisfaction. The sub -categories were again grouped into 14 categories including infant nutritious food, formation of breastfeeding opportunity, feeling of satisfaction, injury of the breast, physical suffering, awareness of mothering, formation of maternal affection, connecting, coupling, acceptance, effort, emotional stability, mother and child health and feeling of achievement.hievement.

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Albizia Fruit Fossils from the Miocene Duho Formation of Yeonil Group in the Pohang Basin, Korea (포항 분지의 마이오세 연일층군의 두호층에서 산출된 Albizia의 열매 화석)

  • Kim, Jong-Heon;Lee, Seong-Bok;An, Ji-Min;Lee, Hye-In;Hong, Han-Sol
    • Journal of the Korean earth science society
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    • v.30 no.1
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    • pp.10-18
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    • 2009
  • Two fruit fossils of Albizia miokalkora were collected from the Miocene Duho Formation of Yeonil Group in the northern Pohang Beach and Changpodong, Gyeongsangbug-do, Korea. The legume is flat and long and has 7 rounded seeds. Although the legume fossils are preserved as impression, they show their whole shape well. It is considered that the fossil Albizia might have flourished in a warm temperate climate in East Asia. This discovery is the second record of Albizia from the Neogene of Korea.

Finite Element Simulation of Material Flow and Weld Line Formation in SMC Compression Molding (SMC 압축성형의 소재유동과 겹침선 형성에 관한 유한요소 해석)

  • Hahn, Young-Won;Im, Yong-Taek
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.1
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    • pp.79-87
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    • 1996
  • SMC(Sheet Molding Compound) is made of unsaturated polyester resin and other additives reinforced with randomly distributed chopped fiberglass strands. Because of its higher stiffness per unit mass, SMC was used as a substitute for steel for automotive steel outer panels. Thus, understanding of flow characteristics during fabrication of SMC is of importance since the formation of weld line depends on material flow. In the present study, SMC compression molding simulations in the flat and T-shape molds were accomplished. During simulations, the preferential the preferential flow occurred at the low mold closing speed while plug flow was observed for the higher mold closing speed. When the preferential flow was observed, the weld line was seen at the final stage. For simulations, rigid-viscoplastic finite element method was applied. Self-contact algorithm was also applied in order to predict the formation of the weld line. Simulation results were compared to the experimental results available in the literature.

A Study on The Burr Formation in Sheet Metal Shearing (박판 전단시의 버 형성에 관한 연구)

  • Shin, Yong-Seung;Kim, Byeong-Hee;Kim, Heon-Young;Oh, Soo-Ik
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.9
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    • pp.166-171
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    • 2002
  • The objective of this paper is to investigate the effect of clearance and the configuration of die system on burr formation by FEM analysis and experimental tests. Compared with casting, forging and machining, shearing has been known, especially in heavy or mass-production industries, as a very economical and fast way to obtain the desired shape Recently, the shearing process becomes widely used in the small and light electronic component manufacturing industries. When shearing a part of sheet metal, the burr formed on the cutting edge is usually unavoidable. The burr would not only degrade the precision of products but also causes additional cost for the deburring process. In this paper, the influence of shearing parameters such as clearance and configurations of the lower pad (ejector) on burr formation is investigated by using the experimental and numerical approach. From the experimental results, it has been shown that the more narrow clearance gives the smaller burr height and the higher shearing forces. The removal of lower holder also makes the sheared surface integrity and the dimensional accuracy become worse. The FEM results (using DEFORM-2D) show good agreement with the experimental results.

Effect of Reverse Transformation Treatment on the Formation of Retained Austenite in 01.5%C-6%Mn Steels (0.15%C-6%Mn강의 잔류오스테나이트 생성에 미치는 역변태 열처리의 영향)

  • Hong, H.;Lee, O.Y.;Lee, K.B.
    • Journal of the Korean Society for Heat Treatment
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    • v.11 no.1
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    • pp.35-45
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    • 1998
  • The effects of alloying elements and the conditions of reverse transformation studied treatment on the formation of retained austenite in 0.15C-6%Mn-(Ti, Nb) steels has been studied. The addition of Ti and Nb to 0.15C-6%Mn steel shows no effect on the formation of retained austenite. In case of reverse transformation treatment at various temperatures, the shape of retained austenite was lath type, growing toward the longitudinal and thickness direction with increasing the heat treatment temperatures. The retained austenite formed by the reverse transformation treatment at higher temperature has a lot of stacking faults induced by the internal stress. The retained austenite was stabilized chemically by enrichment of C and Mn in the vicinity of a untransformed austenite and the chemical stability of retained austenite was decreased with increasing the heat treatment temperature and the holding time. It was effective to heat treat at $650^{\circ}C$ in order to obtain over 30vol.% of retained austenite, but more desirable to heat treat at $625^{\circ}C$ for a long time, considering the amount and quality of retained austenite.

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PEO Film Formation Behavior of Al1050 Alloy Under Direct Current in an Alkaline Electrolyte

  • Moon, Sungmo;Kim, Yeajin
    • Journal of the Korean institute of surface engineering
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    • v.50 no.1
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    • pp.17-23
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    • 2017
  • This work demonstrates arc generation and anodic film formation behaviors on Al1050 alloy during PEO (plasma electrolytic oxidation) treatment under a constant direct current in an alkaline electrolyte containing silicate, carbonate and borate ions. Only one big arc more than 2 mm diameter was generated first at the edges and it was moving on the fresh surface or staying occasionally at the edges, resulting in the local burning due to generation of an extremely big orange colored arc at the edges. Central region of the flat surface was not fully covered with PEO films even after sufficiently long treatment time because of the local burning problem. The anodic oxides formed on the flat surface by arcing once were found to consist of a number of small oxide nodules with spherical shape of $3{\sim}6{\mu}m$ size and irregular shapes of about $5{\sim}10{\mu}m$ width and $10{\sim}20{\mu}m$ length. The anodic oxide nodules showed uniform thickness of about $3{\mu}m$ and rounded edges. These experimental results suggest that one big arc observed on the specimen surface under the application of a constant direct current is composed of a number of small micro-arcs less than $20{\mu}m$ size.

The effect of thermodynamic stability of casting solution on the membrane inversion process morphology and permeation properties in phase inversion process

  • Kim, Jeong-Hoon;Lee, Kew-Ho
    • Proceedings of the Membrane Society of Korea Conference
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    • 1995.04a
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    • pp.26-27
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    • 1995
  • Most of synthetic polymeric membranes used in ultrafiltration, reverse osmosis and microfiltration processes are prepared by phase inversion(or phase separation) technique. In this technique, a homogeneous polymer solution is cast into thin film or hollow fiber shape and then immersed into a nonsolvent coagulant bath. The exchange of solvent and nonsolvent across the interface between casting solution and coagu!ant can make the casting solution phase-separate and form a membrane with a symmetric or asymmetric structure. Because of importance of this technique in membrane field, many investigations have been dedicated to elucidate the mechanism of membrane formation by phase inversion technique.[1-10] These investigation have suggested that the structure formation and permeation properties of phase inversion membrane depend on the variables such as the nature and content of casting solution and coagulant, temperature of casting solution and coagulant, and the diffusional exchange rate of solvent and nonsolvent etc. which can be related to the thermodynamic and kinetic properties of the casting system. The variables such as the nature and content of casting solution can also be the important factor affecting the structure formation and permeation property of the phase inversion membrane.

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A Study on the Effect that Pin Shape and Welding Speed have an Influence on Mechanical Strength in Friction Stir Welding A16061-T6 (A16061-T6 마찰교반용접시 핀 형상과 이송속도가 기계적 강도에 미치는 영향에 관한 연구)

  • Park, Hee-Sang;Lee, Young-Ho;Choi, Won-Doo;Ko, Jun-Bin
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.17 no.4
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    • pp.22-28
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    • 2008
  • Friction stir welding(FSW) is an relatively new solid state joining process. A1606l-T6 aluminium alloy has gathered wide acceptance in the fabrication of light weight structures requiring a high strength to weight ratio and good corrosion resistance. This friction stir process(FSP) uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, etc., and tool pin profile playa major role in deciding FSP zone formation in A16061-T6 aluminium alloy. Tow different tool pin profiles have been used to fabricate the joints. The formation of friction stir processed zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the friction stir processed zone formation.

Astudy on the classification of Eastern Coastal line of korea from the view point of Prevailing Wave Direction (탁월파랑에 의한 동해안선 분류의 조사연구)

  • 이원환;이정태
    • Water for future
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    • v.11 no.1
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    • pp.39-46
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    • 1978
  • The approaching deep water wave heights and directions affect the wave energy which is carried to the coast. By studing the relations between the longshore wave energy theory and the evolution of coastline, writer can arrive following conclusion. The longshore lottoral drifting affects to a great deal the formation of the coast, and by investigating on the eastern coastal geomophorogy of korea, the theory was proued as a true and made it possible to an approaching to the subdivided classification of eastern coast of lorea. That is to asy that angle taken by the level between the wave crest line of prevailing wave(NE) and the coastline was measured as less than 15#, and in the area neighboring the river which served as source of Sand parrticles, there are grand scale formation of sand beach expectable, in the other hand the formation of sand beach in case of $35^{\circ}{\leq}{\alpha }o{\leq}55^{\circ}$ which represents the vivid phenomena of longshore littoral drifting was proved not influencial but rather transformed into a rocky coast. Depending on the above facts the writer classified general shape of the coast affected by the vivid wave action into the following three, (1) The equilibrium beach. (2) Erosinal beach. (3) Geomophorogical beach, and made the sandy and rocky coast are subdivided as S-A.B.C. and R-DEF.

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A Study on the Formation of a Style - Focusing on the Style of Iris Van Herpen - (스타일 형성에 관한 연구 - Iris Van Herpen의 스타일을 중심으로 -)

  • Kim, Yon-Son
    • Journal of Fashion Business
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    • v.16 no.2
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    • pp.124-137
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    • 2012
  • This study aims to identify the meaning and formation cause of a style, and the essential elements of style formation, through psychobiological research as well as an analysis of the designs of Iris Van Herpen, a fashion designer, who in just 6 years has developed into a world-renowned new designer. As a result, it has been found that the psychobiological causes to form a style stem from the action of 'long-term memory', which is consolidated by 'selective attention', 'perceptional subjectivity', the principle of the 'neuron's connection specificity and invariance', and the principle of a 'neuronal signal's unilateral flow'. With such action, Herpen could develop her own original composition techniques. The formative shapes created by such composition techniques are characterized by enumeration, superposition, and hanging. The study has also found that the essential elements for a designer to be able to form his/her own style include 'aesthetic originality' in which the designer views the property of a thing from his/her inherent perspective, and finds the uniqueness from the thing that only he/she can express, 'technical differences' that are creative and original, and 'formative specificity' that is summarized into one property through an impressive shape.