• Title/Summary/Keyword: Physical shape

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Optimization of Two-Step Cold Drawing for Upper Arch-Shape Solid Type Austenitic Stainless Steel (상단 아치 형상 중실 오스테나이트계 스테인리스강의 2단 인발 공정 최적화)

  • Bae, S.J.;Kim, J.H.;Hong, S.B.;Hong, S.K.;Namkung, J.;Lee, K.S.
    • Transactions of Materials Processing
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    • v.31 no.6
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    • pp.394-403
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    • 2022
  • In the automotive industry, cold-drawn austenitic stainless steel is commonly used to handle high fuel pressures in gasoline direct injection (GDI) engines. In this study, we analyzed the effects of main process variables such as cross-sectional shape, drawing speed and friction coefficient on the microstructure, hardness and residual stress of the drawn material in the two-step cold drawing process. By changing the cross-sectional shape in the first-step cold drawing, the possibility of improving the shape accuracy or physical properties of the finally cold-drawn fuel rail pressure sensor product was investigated.

A Study on the Mechanical Press Joining of Double Sheet Metals Using Physical Modeling (물리적 모델링법을 이용한 이중 박판의 기계적 접합 공정에 관한 연구)

  • Kwon, S.O.;Kim, B.J.;Moon, Y.H.
    • Transactions of Materials Processing
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    • v.16 no.2 s.92
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    • pp.107-112
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    • 2007
  • In this study, the mechanical joining process for double sheet metals was investigated by using physical modeling method. Process parameters of mechanical joining such as friction coefficient, drawing depth, pouch radius, die radius and material thickness are preliminarily analyzed by finite element method. Referring to the finite element analysis results mechanical joining system is designed on the basis of physical similarities. From the physical modeling test, the effect of process parameters on the deformation for the mechanical joining are experimentally investigated and optimized joining shape that can provide strong joining strength is obtained.

Relationships between Body Shape, Body Image and Health Complaints in Women Registered at a Facility for Managing Body Shape (여성의 체형과 신체상, 건강문제 호소간의 관계 - 체형관리 시설에 등록한 여성을 대상으로 -)

  • Choi, Euy-Soon;Lee, Kyu-Eun
    • Women's Health Nursing
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    • v.3 no.2
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    • pp.192-207
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    • 1997
  • This study aims at examining relationships between perceived body shape, body image and health complaints among 88 women registered at a facility for managing body shape, which leads to adequate management of obesity in women for healthy lives. The survey was conducted by using a questionnaire consisted of 12 items of general characteristics and interests for weight control, 47 items of body image, and 57 items of Cornell Medical Index(CMI). The data were analyzed by using mean standard deviation, ANOVA, and Pearson correlation coefficient. The results are following. 1. The means of age, body weight, height of the women were 27.02 years, 56.02 years, 56.03kg, 161.71cm, respectively. The level of obesity by body shape was 47.7% for standard type, 26.2% for slim type, 26.1% for fat type. Those women graduated from high school or higher education institutions were 97.7%. 2. More than 70% of the subjects perceived their weight as overweight, while 26.1% of the women were fat according to the level of obesity. Ninety percent of the subjects were not satisfied with their body shape. 3. Body weight increased most during middle and high school days. The women became interested in weight control through talks with friends(35.2%), influence of mass communication(34.1%), and social custom(22.7%). As to the method of weight control, subject's own judgement(54.5%) revealed highest percentage, whereas only 20% of the subjects adopted prescriptions of experts for weight control or of doctors. Those who had side reactions from weight control were 30.7%. High percentages of the women reported the decrease the amount of eating(54.5%), the increase the amount of exercise(27.3%) as the effective methods of weight control. 4. The score of body image differed significantly by the perceived body shape : the score was highest in the perceived standard type. 5. The level of health complaints did not differ by the perceived body shape. In relation to the level of obesity, physical health complaints were high in the groups of very slim type and of very fat type, while mental health complaints were high in the groups of very slim type and of fat type. 6. Very high correlations were observed between the perceived body shape and body image and between physical health complaints and mental health complaints.

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Change of physical property on PET and PTT yarn after heat treatment (PET와 PTT사의 열처리후 물성변화)

  • 김일래;김광수
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.04a
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    • pp.337-338
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    • 2003
  • PTT(poly trimethylene terephthalate)섬유는 PET(polyethylene terephthalate)섬유에 비하여 탄성 (elasticity)가 우수하고 염색성이 PET와 유사한 점에서 차세대섬유로 분류되고 있다. 분자의 구조가 trans-trans의 fully extended chain(rod shape)형태인 PET에 비하여 trans-gauche-gauche-trans의 스프링과 같은 extended zigzag(helix shape)이어서 탄성회복성이 우수하다. 또한 PTT의 탄성계수값은 PET에 비하여 $\frac{1}{2}$정도이다. 의복을 착용중 신장과 수축을 반복하는 과정에서 섬유는 탄성을 점차 상실하게 되는데, 이 응력완화의 변화특성에 따라서 착용감이 영향을 끼친다. (중략)

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STUDY OF CONTACT ION PAIR DYNAMICS IN VIEW OF THE MOLECULAR SHAPES

  • Han, Chul-Hee
    • Journal of Photoscience
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    • v.3 no.3
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    • pp.147-151
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    • 1996
  • Dynamics of contact ion-pair between 1, 2, 4, 5-tetracyanobenzene anion and cation of biphenyl derivatives was investigated on the picosecond time scale. Solvent effect on the electron transfer was observed and electron transfer rates were examined using Marcus equation which contains distance dependence of the electron transfer rate in the frequency factor, along with the consideration of molecular shape. From the discussion based on disk model for molecular shape, contribution of interring torsional motion of biphenyl to the inner-sphere reorganization energy is strongly suggested, which leads to the physical explanation for the observed solvent effect on the rate of electron transfer.

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A Study on features and Interpretation of Placeness of Rem Koolhaas' Architecture (렘 콜하스 건축의 장소적 특성과 해석에 관한 연구)

  • Park, Hyung-Jin;Kim, Moon-Duck
    • Korean Institute of Interior Design Journal
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    • v.16 no.2 s.61
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    • pp.87-96
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    • 2007
  • This study analyzes the place of modem architecture based on the place theory of C. N, Schultz. For applying Schultz's theory to the modern architecture, It is required to examine the modern cityscape, features of inner space of architecture and features of program. By analyzing the avant-garde architecture of Rem Koolhaas on such basis, the potentiality of placeness of modern architecture could be verified and the alternatives would be searched. It is inferred that the placeness features of Rem Koolhaas' public architecture is under the influence of the interpretation of program based on the humane background rather than the physical aspects of surroundings. The inner space shows the non-linear features, the metaphor of city. The obscurity of physical boundary illustrates the flexible features with ambiguous boundary. Consequently, the inner space expresses the surreal atmosphere that doesn't match the purposes of usage of architecture, the traditional concept. The outer shape is recognized as the by-product from the interpretation of internal program rather than it considered the surrounding context. The outer shape has the relatively simple formative shape and contrasts against the complicated inner space by using the non-physical materials. It is found that Koolhaas' architecture doesn't pursue the features of placeness of traditional concept. However, It is inferred that his architecture has the possibility of placeness by attaching the meaning through the social roles of each architecture. It gives the substantial suggestion to the modern architecture that can't easily acquire the placeness of traditional concept due to the environment of modern city.

Effect of the Shape and Size of Quorum-Quenching Media on Biofouling Control in Membrane Bioreactors for Wastewater TreatmentS

  • Lee, Seonki;Lee, Sang Hyun;Lee, Kibaek;Kwon, Hyeokpil;Nahm, Chang Hyun;Lee, Chung-Hak;Park, Pyung-Kyu;Choo, Kwang-Ho;Lee, Jung-Kee;Oh, Hyun-Suk
    • Journal of Microbiology and Biotechnology
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    • v.26 no.10
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    • pp.1746-1754
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    • 2016
  • Recently, spherical beads entrapping quorum quenching (QQ) bacteria have been reported as effective moving QQ-media for biofouling control in MBRs for wastewater treatment owing to their combined effects of biological (i.e., quorum quenching) and physical washing. Taking into account both the mass transfer of signal molecules through the QQ-medium and collision efficiencies of the QQ-medium against the filtration membranes in a bioreactor, a cylindrical medium (QQ-cylinder) was developed as a new shape of moving QQ-medium. The QQ-cylinders were compared with previous QQ-beads in terms of the QQ activity and the physical washing effect under identical loading volumes of each medium in batch tests. It was found that the QQ activity of a QQ-medium was highly dependent on its specific surface area, regardless of the shape of the medium. In contrast, the physical washing effect of a QQ-medium was greatly affected by its geometric structure. The enhanced anti-biofouling property of the QQ-cylinders relative to QQ-beads was confirmed in a continuous laboratory-scale MBR with a flat-sheet membrane module.

Allowable limit of physical optics in radar cross section analysis of edge shape (가장자리 형상의 레이더 반사 면적 해석에서 물리광학기법의 적용 한계)

  • Baek, Sang-Min
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.46 no.1
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    • pp.78-85
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    • 2018
  • As a numerical analysis technique to predict the radar cross section of an aircraft, a full wave method or an asymptotic method is mainly used. The full-wave method is expected to be relatively accurate compared with the asymptotic method. The asymptotic method is numerically efficient, and it is more widely used in the RCS analysis. However, the error that occurs when estimating the RCS using the asymptotic method is difficult to predict easily. In this paper, we analyze the allowable limits of physical optics by constructing a wedge-cylinder model and comparing the RCS prediction results between the method of moment and physical optics while changing the edge shape. Finally, this study proposes a criterion for allowable limit of physical optics in the RCS estimation.

Analysis of Brain Activation due to Mouth Shape during Grip Movement (잡기동작 수행 시 입모양에 따른 뇌활성화 분석)

  • Shim, Je-Myung;Kim, Hwan-Hee;Kim, Chung-Sun
    • Journal of the Korean Society of Physical Medicine
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    • v.5 no.3
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    • pp.467-476
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    • 2010
  • Purpose : This study was performed to understand the relationship between hand and mouth shapes using functional magnetic resonance imaging(fMRI). Methods : Two healthy volunteers without any previous history of physical or neurological illness were recruited. fMRI was done that volunteers was 6 repeated of natural mouth, close mouth and open mouth while power grip and pinch grip movement. Results : Cerebral cortex activation was not well observed for the natural mouth during the power grip exercise. For the closed mouth, the temporal lobe, Broca's area, the prefrontal area related to thinking and judgment, the supplementary motor area, the auditory area and Wernicke's area were activated. For the open mouth, cortical activation was also observed in the temporal lobe, Wernicke's area, the prefrontal area related to thinking and the orbital frontal area related to visual sense. During the pinch grip exercise, cortical activation was observed for the natural mouth in the primary sensory area, Wernicke's area, the primary and supplementary motor area, and the prefrontal area. For the closed mouth, cortical activation was observed in the temporal lobe, Wernicke's area, the prefrontal area related to thinking, the secondary visual area, the primary sensory area and the supplementary motor area. In the case of the open mouth, cortical activation was observed in a few parts in the temporal lobe as well as Wernicke's area, the prefrontal area related to thinking, and other areas related to visual sense such as the primary visual area, the secondary visual area and the visual association area. Conclusion : Brain was more activation for close mouth and open mouth more than natural mouth movement.

Clothing and Hairstyle Behavior Dependence on the Physical Characteristics of college Women (여대생의 신체적 특징에 따른 의복행동 및 헤어스타일 행동에 관한 연구)

  • Bark Ju Bee,;Jung Ok Im,
    • Journal of the Korean Home Economics Association
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    • v.43 no.6 s.208
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    • pp.97-112
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    • 2005
  • The purpose of this study was to examine how female college students' physical characteristics affect their and hairstyle behavior. The study methodology was a survey, with questions gathered from the previous research surveys and collated by the author. The study subjects 350 female college students in Gwangju, Korea. This survey was performed from November 8thto 13th 2004, and 348 questionnaires were finally used for the study analysis.. The research results are summarized as follows: 1. As a result of the analysis on the research variants, costume behavior was derived from four factors clothing sympathy, clothing exhibition, clothing convenience, clothing aesthetics. Hairstyle behavior was derived from five factors: hair sympathy, hair individuality, hair aesthetics, dependency on hair designer, and hair convenience. 2. The difference between clothing and hairstyle behavior according to physical characteristics showed that clothing and hairstyle behavior make a significant difference according to the height, weight, study major, spending money, and family income. 3. There was a positive correlation among clothing and hairstyle behavior clothing Female college students showed the same differences in clothing behavior as in hairstyle behavior according to their own physical characteristics. When more satisfied with their body shape, they tended to pursue a clothing aesthetic. When more dissatisfied with their body shape, they tended to pursue a comfortable and acceptable look, which does not attract others' attention, rather than pee the changes of hairstyle and fashion.