• Title/Summary/Keyword: Parent materials

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A Study on Efficient Analysis of Delamination Buckling of Composite Structures (효율적인 복합재료구조물의 delamination buckling 해석기법에 관한 연구)

  • 황재웅;김용협
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2000.04a
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    • pp.80-84
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    • 2000
  • A mesh superposition technique is presented for an efficient analysis of structural behavior. Refined child mesh is superimposed over parent elements for the region of interest. It is a kind of adaptive mesh refinement, which allows locally refined mesh without introducing transition region or multipoint constraints. Proper boundary condition is necessary to avoid redundant rigid body motion and kinematic compatibility between neighbor elements. Delamination buckling analysis is conducted to demonstrate accuracy and efficiency of the present method.

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Mn-deprived Phase Transformation in High-Mn Steel during the Dew-point Control Process

  • Hong, Woong-Pyo;Baik, Sung-Il;Kim, Gyo-Sung;Jeon, Sun-Ho;Chin, Kwang-Guen;Oh, Chang-Seok;Kim, Young-Woon
    • Applied Microscopy
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    • v.43 no.1
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    • pp.40-45
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    • 2013
  • Phase transformation by the Mn-deprivation was observed in the high-Mn twinning-induced plasticity-aided steel. Mn-depletion was induced by the formation of Mn-O oxide during the dew-point control process at temperature above $-20^{\circ}C$, which changed austenitic parent phase to multi-grained ferrite. Mixture of Al-O, Al-Mn-Si-O oxides were observed at the grain boundaries of transformed ferrite.

Hydrogenation of Phenylacetylene to Styrene on Pre-CxHy- and C-Covered Cu(111) Single Crystal Catalysts

  • Sohn, Young-Ku;Wei, Wei;White, John M.
    • Bulletin of the Korean Chemical Society
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    • v.32 no.5
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    • pp.1559-1563
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    • 2011
  • Thermal hydrogenation of phenylacetylene (PA, $C_8H_6$) to styrene ($C_8H_8$) on pre-$C_xH_y$- and C-covered Cu(111) single crystal substrates has been studied using temperature-programmed desorption (TPD) mass spectrometry. Chemisorbed PA with an acetylene group has been proved to be associated with hydrogen of pre-adsorbed $C_xH_y$ to form styrene (104 amu) on Cu surface. For the parent (PA) mass (102 amu) TPD profile, the TPD peaks at 360 K and 410 K are assigned to chemisorbed vertically aligned PA and flat-lying cross-bridged PA, respectively (J. Phys. Chem. C 2007, 111, 5101). The relative $I_{360K}/I_{410K}$ TPD ratio dramatically increases with increasing pre-adsorbed $C_xH_y$ before dosing PA, while the ratio does not increase for pre-C-covered surface. For PA on pre-$C_xH_y$-covered Cu(111) surface, styrene desorption is enhanced relative to the parent PA desorption, while styrene formation is dramatically quenched on pre-C-covered (lack of adsorbed hydrogen nearby) surface. It appears that only cross-bridged PA associates with adsorbed hydrogen to form styrene that promptly desorbs at 410 K, while vertically aligned PA is less likely to participate in forming styrene.

Evaluation of Scc Susceptibility of Welded HAZ in Structual Steel(II) -Frcature Behavior in Cathodic Protection- (강 용접부의 응력부식크랙 감수성 평가에 관한 연구 II -음극방식에서의 파괴거동-)

  • 임재규;조정운;나의균
    • Journal of Welding and Joining
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    • v.11 no.3
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    • pp.61-74
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    • 1993
  • The cause of corrosion failure found in structures or various components operating in severe corrosive environment has been attributed to stress corrosion cracking(SCC) which is resulting from the combined effects of corrosive environments and static tensile stress. Cathodic protection is an electrochemical method of corrosion control that is widely used in marine environment and primarily on carbon steel. A number of criteria are used to determine whether or not a structure is cathodically protected. In practice, -0.8V versus Ag/AgCl is the most commonly used for marine structures. This paper showed the combined effects of cathodic potential and slow, monotonic straining on the tensile ductility and fracture morphology of parents and friction welded joints for SM45C, SCM440 and SM20C steels in syntheic sea water(S.S.W.,pH:8.2). For the parent materials in cathodic potentials, the higher tensile strength is, the more susceptible SCC is. And the welded HAZ is more susceptible than the parent materials.

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A Study on Educational Needs in Married Immigrant Women Perceived by Their Home Visiting Educator (방문교육지도사가 인지하는 여성 결혼이민자의 교육요구)

  • Kim, Mi-Jong;Kim, Tae-Im;Kwon, Yun-Jung
    • Korean Parent-Child Health Journal
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    • v.13 no.1
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    • pp.44-53
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    • 2010
  • Purpose: This study was conducted to identify the educational needs of married immigrant women perceived by their home visiting educator. Methods: Data were collected using in-depth interviews and structured questionnaires during July 1st to 28th, 2009. 5 HVEs participated in focus group interview, and 27 HVEs in the questionnaire survey. Data were analyzed by content analysis and descriptive statistics using SPSS/WIN program. Results: Educational needs of Married Immigrant Women were conjugal and family relationship, child rearing and child health care, health management, sex education, and self-identification. There is no proper teaching materials about child rearing for HVEs. The educational needs of HVEs were physical and cognitive characteristics of child development, developmental screening skill and play according to the each developmental stages of the multi-cultural families. Conclusion: Family relationship, child rearing and child health care, must be stressed in educational program for Married Immigrant Women. To maximize the effectiveness of support for multi-cultural families, it must be developed a systematic educational program and teaching materials according to family developmental stages.

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Characterization of potassium supplying power of paddy soils by 40K application (40K 자연방사능(自然放射能)을 이용(利用)한 한국답토양(韓國沓土壤)의 가리공급력(加里供給力)에 관(關)한 연구(硏究) (I))

  • Kim, Tai Soon;Han, Kang Wan;Bai, Young Ja
    • Korean Journal of Soil Science and Fertilizer
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    • v.4 no.1
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    • pp.33-40
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    • 1971
  • Using radioactive $^{40}K$ in potassium, a study was conducted to evaluate the potassium supplying power of different soil types developed on different parent materials. A conversion factor based on two parameters namely $\frac{available\;K_{soil}}{total\;K_{soil}}$ and $\frac{K_{plant}}{K_{soil}}$ was developed and found to be closely related to plant response. According to this characterization soils derived from the various parent materials were ranked as basalt >Silla series>gneiss>porphyry>granite${\gg}$schist. From the point of view of potassium response as measured by yield as similar response pattern was observed. That is, soils derived from basalt to be most responsive as compared to the other soils. The variations among the soils may be accounted for to their potassium bearing mineralogical composition and their stability.

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A Study on the Ego State Types of Teacher Librarians (사서교사의 자아 상태 유형에 대한 연구)

  • Song, Gi Ho
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.25 no.2
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    • pp.77-95
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    • 2014
  • The purpose of this study is to analyze ego state types of teacher librarians by using egogram of the Transactional Analysis. It is the ideal ego state types for teachers that NP (Nurturing Parent), A (Adult) and FC (Free Child) are much higher than CP (Critical Parent) and AC (Adapted Child). But the teacher librarians are under higher CP and AC rather than A and FC. It means that the teacher librarians consider their values and belief as right things. Also it seams that they have not a conciliatory attitude but a hardened attitude that emphasize rules and standards. These ego state may be obstacle to their instructors role under the constructivist learning environment highlighting self directed learning of students. So, in the training course for the teacher librarians, informational and educational service course and development programs of education contents and instructional materials should be reinforced in order to strengthen their teaching competence and partnerships.

A Study on Maternal Verbal Control Pattens and Children's Recognition against those (어머니의 언어통제유형과 그에 대한 아동의 인지 연구)

  • 이희자
    • Journal of the Korean Home Economics Association
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    • v.30 no.4
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    • pp.231-247
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    • 1992
  • A Study on Maternal Verbal Control Patterns and Children's Recognition against those. The primary objective of the material presented in this dissertation is the analysis of the maternal verbal control patterns. The major focus is given to the differences between maternal verbal control patterns and children's recognition against those. The purspoe of this study were; 1) to investigate the maternal verbal control patterns recognized by children according to their family and personal surroundings; 2) to investigate the verbal control patterns in mother's response according to the differences of family and personal surroundings; 3) to find the differences between children's recognition and maternal verbal control patterns; 4) How the maternal verbal control patterns recognized by children are? The materials of this study were 81(37; boys, 44; girl)) from kindergarten in Seou. The sample of age used in this study was 5 to 7 years old. The test about maternal verbal environment used the question sheet for reaction between mother and children by Gumperz. The kids got interviews with same questions as mothers with question sheet. The statistical tools used is the analysis of the data were frequency, crosstab, and t-test. The result of the study were summarized as follows; 1) The maternal verbal control patterns recognized by children had differences according to whether living with grand-parent or not. Living with grand-parent are more person-oriented than without grand-parent group. 2) The maternal verbal control patterns of mother response show the differences within mother's academic background, present situation of child, and parent's expection to child. The imperative verbal control pattern was more frequently used of low academic background who just fraduate the middle or high school. The personal verbal control pattern was more frequently used of high educational background's like university graduate or more educated group. 3) The differences between maternal verbal control patterns with children's recognition and with mother response is that mother responseis more person-oriented than children's. 4) The imperative verbal control pattern used command, verbal purnishment, and physical purnishment. the status-oriented verbal control pattern used univesal positional appeals and limited positional appeals. The person-oriented verbal control pattern used child-oriented cognitive affective appeals.

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A Study on Hot Straining Embrittlement of Subcritical HAZ in Steel Weldments (강 용접 열영향부 취화역 의 열변형취화 에 관한 연구)

  • 정세희;김태영;임재규
    • Journal of Welding and Joining
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    • v.3 no.2
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    • pp.35-41
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    • 1985
  • The fracture toughness of subcritical HAZ in the hot strained weldments of two structural steels(SB 41 and SA 537) has been investigated by COD test method and metallurgical study. The obtained results are summarized as follows; 1. The hot straining embitterment of subcritical HAZ depends on the hot straining amounts of notch tip, and the transition temperature( $T_{tr}$ ) increases with the accumulated hot straining amounts(.SIGMA. vertical bar .delta.$_{t}$vertical bar). 2. The fracture toughness of subcritical HAZ depends on materials and microstructure. The transition temperature( $T_{tr}$ ) of subcritical HAZ in SB 41 is almost same as that of parent material, however in SA 537 the temperature is higher than that of parent and lower than that of transformed HAZ. 3. The subcritical HAZ in SA 537 shows a higher toughness at small amounts of hot straining (.SIGMA. vertical bar .delta. $_{t}$vertical bar<0.3mm).mm).

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State of Parent Education and of Child Education at Home Related to Infant/Preschooler Abuse Prevention (영유아 학대예방 관련 부모교육 및 가정에서의 자녀교육 실태)

  • Sung, Young Hwa;Lee, Suk Ja
    • Korean Journal of Child Education & Care
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    • v.18 no.1
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    • pp.125-146
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    • 2018
  • The purpose of this study was to examine the state of parent education experienced by parents and the state of child education at home relation to infant/preschooler abuse prevention. The subjects in this study were 302 selected parents who resided in I city and whose children were in infancy or early childhood. A survey was conducted, and frequency analysis or chi-square test was carried out after their answer sheets were gathered. The findings of the study were as follows: As for the state of parent education, the parents who received education related to infant/ preschooler abuse prevention accounted for 12.6 percent, and the parents who were taught about all the four types of abuse outnumbered the others who weren't. The parents received that education at institutions for early childhood education by experts in child abuse and early childhood education, and they replied they were satisfied with that education. As for the state of child education, the parents who replied they provided abuse prevention education for their children at home accounted for 25.2 percent, and they answered they taught about physical abuse and how to cope with abuse. They responded they started to conduct this education in their homes when their children were in infancy, and they did it frequently in daily life mainly through conversations. They told it's difficult for them to offer this education at home due to a shortage of abuse-related materials. And whether they offered that education for their children or not at home was significantly different according to whether they received parent education or not. Given the findings of the study, the necessity of the development of manuals for abuse prevention education that can easily be used at home without any modifications was suggested, and education on neglect and the revitalization of publicity are required as well.