• 제목/요약/키워드: f-factor

검색결과 2,685건 처리시간 0.031초

J-적분과 균열선단개구변위에 관한 구속계수 m의 평가 (An Estimation of Constraint Factor on the ${\delta}_t$ Relationship)

  • 장석기
    • Journal of Advanced Marine Engineering and Technology
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    • 제24권6호
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    • pp.24-33
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    • 2000
  • This paper investigates the relationship between J-integral and crack tip opening displacement, ${\delta}_t$ using Gordens results of numerical analysis. Estimation were carried out for several strength levels such as ultimate, flow, yield, ultimate-flow, flow-yield stress to determine the influence of strain hardening and the ratio of crack length to width on the $J-{\delta}_t$ relationship. It was found that for SE(B) specimens, the $J-{\delta}_t$ relationship can be applied to relate J to ${\delta}_t$ as follows $J=m_j{\times}{\sigma}_i{\times}{\delta}_t$ where $m_j=1.27773+0.8307({\alpha}/W)$, ${\sigma}_i:{\sigma}_U$, ${\sigma}_{U-F}={\frac{1}{2}} ({\sigma}_U+{\sigma}_F$), ${\sigma}_F$, ${\sigma}_F}$ $Y=({\sigma}_F+{\sigma}_Y)$, ${\sigma}_Y$

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압출공정 스크류특성 결정을 위한 전체 형상계수 (A Total Shape Factor for Determining Three-Dimensional Screw Characteristics of Extrusion Process)

  • 김시조;권태헌
    • 대한기계학회논문집
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    • 제18권10호
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    • pp.2533-2542
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    • 1994
  • This paper suggests a simple approach to determining the screw characteristics for a three0dimensional flow in a channel with a finite aspect ratio(ratio of a width to a depth, W/H) by introducing a Total Shape Factor($F_t$) to correct a two-dimensional flow analysis for a channel with an infinite aspect ratio. In the present study, the Total Shape Factor($F_t$) was defined as a ratio of a net flow rate obtained by the three-dimensional analysis to that by the two-dimensional analysis. In the proposed approach, the quantity, $ \frac{{\partial}F_t}{\partial(H/W)}$ turns out to be almost constant and to play an important role in understanding the effects of the flights. Therefore, $ \frac{{\partial}F_t}{\partial(H/W)}$ are extensively reported in this paper in terms of several dimensionless parameters. This simple approach with such database will be very useful for extruder designers to predict the screw characteristics.

여성구두의 상표이미지 평가와 상표선호도에 관한연구 (A Study on the Image Evaluation and preference of Brand Name of Women's Shoes)

  • 장윤정
    • 복식
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    • 제33권
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    • pp.27-39
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    • 1997
  • The purpose of this study was to classify the attributes of brand image criteria of women's shoes to compose the perceptual map of the brand by factor analysis and to examine the differences in brand preferences and purchase methods of shoes according to demographic variables. 10 brand names were selected for the study Samples were 271 women in Seoul Korea :143 were college students and 128 were career women.The data were analyzed using factor analy-sis multiple regression analysis one-way ANOVA Duncan's multiple range test x2-test t-test. The results of the study were the -followings: 1. Four segments of brand image attributes of women's shoes derived by factor analysis: F. 1. 'utility' F.2'appearance' ; F. 3 'sales promotion' ; F.4 'financial factor'. 2. As the result of draw up the perceptual map 'landrover' was high in utility but low in appearance 'Misope' and 'Mook' was low in utility but high in appearance. 'Fashion Leader' was in the nearest ideal direction to the utility and appearance. 3. The preference level of the shoes brand name was in order of the 'Fashion Leader'. 'Mook' and 'Soda' But consumers possessed 'Landrover' the most 4. There were significant differences among preference level of ' Landrover' and 'Misope' according to the social class. There were sig-nificant differences among possession level of 'Misope' and 'Soda' according to the social class 5. the middle and lower class consumers used an exchange ticket during the bargain sales more than upper class when they pur-chase shoes.

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PSN-PMN-PZT 세라믹스의 Zr/Ti 비에 따른 전기적 특성과 공진주파수의 온도안정성 (Electrical Properties and Temperature Stability of resonant Frequency with Zr/Ti ratio in PSN-PMN-PZT Ceramics)

  • 류주현;윤광희;민석규;이명수;서성재
    • 한국전기전자재료학회논문지
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    • 제13권8호
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    • pp.675-680
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    • 2000
  • In this study the temperature coefficient of resonant frequency(TC $F_{r}$) dielectric and piezoelectric properties of Pb[(S $b_{1}$2//N $b_{1}$2/)$_{0.065}$)-(Z $r_{x}$, $Ti_{1-x}$ )$_{0.90}$] $O_3$ceramics were investigated with Zr/Ti ratio. The compositions near the morphotropic phase boundary (MPB) appeared when Zr/Ti ratio was 49.5/50.5 The dielectric constant and electromechanical coupling factor( $k_{p}$) also showed the highest values of 1,257, 0.653 respectively when the Zr/Ti ratio was 49.5/50.5 Moreover the mechanical quality factor( $Q_{m}$) showed th lowest value of 713 when the Zr/Ti ratio. The temperature coefficient of resonant frequency(TC $F_{r}$) abruptly change at the morphotropic phase boundary(MPB) which existed between the rhombohedral phase with highly negative TC $F_{r}$ of -106ppm/$^{\circ}C$ and the tetragonal phase with highly positive TC $F_{r}$ of +64pp $m^{\circ}C$ as Zr/Ti ratio varied from 50/50 to 49.5/50.5.50.5..50.5.

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PSN-PMN-PZT 세라믹스의 유전 및 압전 특성과 공진 주파수의 온도안정성 (Dielectric, Piezoelectric Properties and Temperature Stability of Resonant Frequency in PSN-PMN-PZT Ceramics)

  • 윤광희;류주현;민석규;이명수;서성재
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.391-395
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    • 2000
  • In this study, the temperature coefficient of resonant frequency(TC $F_{r}$), dielectric and piezoelectric properties of Pb[(S $b_{1}$2/N $b_{1}$2/)$_{0.0035}$-(M $n_{1}$3/N $b_{2}$3/)$_{0.0065}$-(Z $r_{x}$ $Ti_{1-x}$ )$_{0.90}$] $O_3$ceramics is investigated with Zr/Ti ratio. The dielectric constant and electromechanical coupling factor( $k_{p}$) showed the highest values of 1257, 0.562 respectively when the Zr/Ti ratio is 49.5/50.5. The mechanical quality factor( $Q_{m}$) is the lowest value of 713 when the Zr/Ti ratio is 49.5/50.5, and increased with the decrease of the Zr/Ti ratio. The temperature coefficient of resonant frequency(TC $F_{r}$) change abruptly at the morphotropic phase boundary(MPB), which is between the rhombohedral phase with highly negative TC $F_{r}$ of -106ppm/$^{\circ}C$ and the tetragonal phase with highly positive TC $F_{r}$ of +64pp $m^{\circ}C$ as Zr/Ti ratio changes from 50/50 to 49.5/50.5.50.5..5.50.5.5.

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Fatigue Strength Assessment of Spot-Welded Lap Joint Using Strain Energy Density Factor

  • Sohn, Ilseon;Bae, Dongho
    • Journal of Mechanical Science and Technology
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    • 제15권1호
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    • pp.44-51
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    • 2001
  • One of the recent issues in design of the spot-welded structure such as the automobile body is to develop an economical prediction method of the fatigue design criterion without additional fatigue test. In this paper, as one of basic investigation for developing such methods, fracture mechanical approach was investigated. First, the Model I, Mode II and Mode III, stress intensity factors were analyzed. Second, strain energy density factor (S) synthetically including them was calculated. And finally, in order to decide the systematic fatigue design criterion by using this strain energy density factor, fatigue data of the ΔP-N(sub)f obtained on the various in-plane bending type spot-welded lap joints were systematically re-arranged in the ΔS-N(sub)f relation. And its utility and reliability were verified by the theory of Weibull probability distribution function. The reliability of the proposed fatigue life prediction value at 10(sup)7 cycles by the strain energy density factor was estimated by 85%. Therefore, it is possible to decide the fatigue design criterion of spot-welded lap joint instead of the ΔP-N(sub)f relation.

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패션점포 판매원의 의복과 점포유형이 노년여성소비자들의 호감과 구매의도에 미치는 영향 (The effects of a fashion store saleswomans clothing and store type on elderly female consumers likability and intention to purchase)

  • 전호경;황선진
    • 한국의류학회지
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    • 제25권2호
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    • pp.293-302
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    • 2001
  • The purpose of this study was to investigate the effects of a saleswomans clothing and store type on elderly female consumers likability to a saleswoman. Also it was to study the effects of the factors consisting likability to a saleswoman on intent to purchase among elderly female consumers. 3(clothing formality: low, medium, and high)$\times$2(clothing style: clothing looking old vs. young)$\times$2(store type: high priced specialty store vs. low priced open market) complete randomized between subjects design using field experiments were conducted. Subjects were 240 elderly females aged 54-69. The results showed that likability to a saleswoman consisted of impression factor, service ability factor and caring factor. There was the significant three way interaction among three independent variables in the service ability factor(F(sub)2,228=15.62, P<.001). Regression Analysis showed that the impression factor($R^2$=0.29, F<.001) and the service ability factor($R^2$=0.06, F<.001) influenced the elderly consumers intention to purchase significantly. In conclusion, favorable appearances of a saleswoman is considered a crucial service quality influencing potential elderly consumers to purchase.

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남성의 라이프 스타일과 매일의 의복선택동기에 관한 연구 (A Study on Life Style and Daily Clothing Selection Motives of Men)

  • 한화숙
    • 복식
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    • 제28권
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    • pp.137-150
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    • 1996
  • The objectives of this study were to classify daily clothing selection motives and to group men into life style types and to examine the differences in daily clothing selection motives according to the life style types. Questionnaire comprised of three sections: 36 Likert type items of life style measure; 29 Likert type items of daily clothing selection motives measure: and 4 demographic variables. Samples were 267 salary men in gheir 20's to 30's in Seoul Korea. The data were analyzed using factor analy-sis cluster analysis one-way ANOVA Dun-can's multiple range test and t-test. 1. Five factors of life style were derived by factor analysis ; F. 1 'appearance oriented' f. 2. 'positive activity' F. 3 'economy oriented': F.4 'active-leisure';F. 5 'contemporary' Four types of life style of men were defined by cluster analysis of the five factors: T. 1'posi-tive activity'; T. 2.'economy interest'; T. 3'contemporary' : T 2'economy interest' T.3'contemporary' ; T. 4 'appearance interest' 2. Four factors of daily clothing selection motives were derived by factor analysis: F.1 'clothing harmony'; F.2 'clothing utility'; F.3 'psychological influence'; F.4 'exogenous situ-ation adaptation 3. There were significant differences in daily clothing selection motives according to the life style types. The types of positive activity economy interest and contemporary had 'clothing utility' motive more than appearance interest type. Economy interest type had 'hpsychological influence' motive more than other three types. Economy interest type and appearance interest type had 'exogenous situ-ation adaptation' motive more than other two types 4. 20's and unmarried men had'psychological influence' motive more than 30's and married. Upper class had 'clothing harmony' and 'ex-ogeneous situation adaptation' motives more than middle and low. Men with less education had ' clothing utility' and 'exogenous situation adaptation' motives more than did more edu-cation.

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추동용 니트웨어 구매행동과 착용감에 관한 연구 (A Study of Purchase behavior and Wearing sensation of F/W Season Knit Wear)

  • 박순천;이영주
    • 한국생활과학회지
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    • 제18권2호
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    • pp.431-439
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    • 2009
  • This research aims to invest consumers' purchase behavior and preference of F/W season knit wear to prepare for basic data in producing competitive knit wear which can meet consumers' demands. The results are as follows: 1. Consumers in their twenties are largely purchasing their knit wear at bonded clothing shops, consumers in their thirties at outlet stores and consumers in their forties and fifties at department stores. As for preferred materials in knit wear, the twenties like 100% of cotton, the thirties mixed wool, and the forties and the fifties 100% of wool. Across all age groups, they prefer knit wear pattern with no figures, while they consider its design and color as important factors in purchasing F/W knit wear. 2. As for the wearing sensations of F/W knitwear of three age groups, there are not significant differences in other factors except a factor of 'jacket length'. 3. As for the fitting sensation about F/W knit wear, consumers with 'thin' somatotype feel high comfort in the factor of 'girth', while consumers with standard somatotype feel high satisfaction in the factor of 'length'.

The inhibitory effect of egg white lysosome extract (LOE) on melanogenesis through ERK and MITF regulation

  • Park, Jung Eun;Hwang, Hyung Seo
    • Journal of Applied Biological Chemistry
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    • 제65권2호
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    • pp.93-99
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    • 2022
  • Lysosome organelle extract (LOE) was derived from egg whites. The lysosome is an intracellular organelle that contains several hydrolysis enzymes. Previous studies have reported that LOE performs important functions, such as melanin de-colorization and anti-melanin production in B16F10 melanoma cells. However, its principal molecular and cellular mechanisms have not been elucidated till date. In non-cytotoxic conditions, LOE significantly inhibited α-MSH induced melanin synthesis of murine B16F10 cells. The anti-melanogenic activity of LOE was mediated by suppressing the mRNA expression of tyrosinase enzyme, tyrosinase related protein-1/2 (TRP-1/2), and microphthalmia-associated transcription factor (MITF) genes. By performing western blot analysis, we found that LOE significantly attenuated melanogenesis. In this case, LOE helped in increasing extracellular receptor kinase (ERK) phosphorylation in α-MSH induced B16F10 cells. Furthermore, MITF is found to be a key regulatory transcription factor in melanin synthesis; it was down-regulated by LOE through ERK phosphorylation. In this experiment, PD98059 (MEK inhibitor) was used to check whether LOE directly regulated the activity of ERK. Although LOE exerted inhibitory effect on melanin synthesis, we could not observe this effect in PD98059-treated α-MSH induced B16F10. These results strongly indicate that LOE is related to ERK activation and MITF degradation in anti-skin pigmentation. Hence, LOE should be utilized as a whitening agent of skin in the near future.