• Title/Summary/Keyword: Depth factor

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Observation on Neck Form Changes Related to Aging in Men (Part III) -by the Somatometric Data and the Principal Component Ana]isis- (성인남자 목부위의 연령별 형태변화에 관한 연구(제3보) -직접계측치와 주성분 분석에 의한 해석-)

  • 이영숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.19 no.3
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    • pp.463-470
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    • 1995
  • Anthropological measurements concerning 29 items were made on 37 adult males aged from 20 to 60. Factor analysis was applied in all 36 items. The main results are as gallows 1. Neck girth and need base girth are smaller. in the elder croup than the gouger group. 2. These decrease occur in the frontal part of the neck. 3. Neck frontal width decreases with age, but side depth increases. 4. The back part of the body depth at the level of the shoulder increases with age. 5. For the factor analysis, the third factor is a factor of forms, the variations of which has a relation with age.

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Effects of the Grinding Conditions on the Machining Elasticity Parameter

  • Kim, Kang
    • International Journal of Precision Engineering and Manufacturing
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    • v.4 no.3
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    • pp.62-67
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    • 2003
  • The grinding force generated during the grinding process causes an elastic deformation of the workpiece, grinding wheel, and machine system. Thus, the true depth of cut is always smaller than the apparent depth of cut. This is known as machining elasticity phenomenon. The machining elasticity parameter is defined as a ratio between the true depth of cut and the apparent depth of cut. It is an important factor to understand the material removal mechanism of the grinding process. To increase productivity, the value of this machining elasticity parameter must be large. Therefore, it is essential to know the characteristics of this parameter. The objective of this research is to study the effect of the major grinding conditions, such as table speed, depth of cut, on this parameter experimentally, Through this research, it is found that this parameter value is increasing when the table speed is decreasing or the depth of cut is increasing. Also, this parameter value depends on the grinding mode (up grinding, down grinding).

A Study on the Trend of Bodytype Change -On the adult male between age 19 and 54- (체형의 변이 경향에 대한 연구 -우리나라 19~54세 남성을 대상으로-)

  • 김구자;이순원
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.1
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    • pp.218-227
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    • 1996
  • The purpose of this study was performed to analyze the trend of bodytype change of adult males. Subjects were 1290 Korean adult males and their age range was from 19 to 54 year, ; old. 75 variables(66 variables from the direct anthropometric data and 9 variables from the multiplication method) in total were applied to analyze. The principal component analysis was applied to the data with orthogonal rotation after extraction of major factors. The high factor loading items extracted by factor analysis were analyzed for the trend of bodytype change by the age group respectively. The result of factor analysis indicated that the first factor was composed with about 30 items, girth, depth and width-measures in 4 age groups and was analysed as form factors. Especially, age-related change was caused by increase of waist girth, depth and width. The second factor was composed with about 23 items, length and height-measures in all age groups. Stature has a constant factor loading value in 4 groups. Front and back waist-height and the navel-height have the highest factor loading value. The third, fourth and fifth factors were composed with different variables among the age groups.

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An Analysis for the Characteristics of Headward Erosion and Separation Zone due to Bed Discordance at Confluence (합류부 하상고 불일치에 의한 두부침식 및 분리구역 특성분석)

  • Choi, Heung Sik;Mo, Sun Jea;Lee, Sam Hee
    • Journal of Korea Water Resources Association
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    • v.48 no.11
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    • pp.879-889
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    • 2015
  • The pattern of headward erosion at tributary and the separation zone formation in a loosed bed at confluence according to the confluence angle, discharge ratio, and dredging depth ratio have been analyzed. The separation zone is defined the inside of zero velocity boundary at downstream of confluence. The limit of separation zone occurrence is presented with dredging depth ratio. The propagation length of knickpoint increases as the confluence angle, discharge ratio, and dredging depth ratio increase in general and its regression equation has been suggested. The length and width ratios of separation zone in a loosed bed increase as discharge ratio and confluence angle increase as well as in a fixed bed. The length ratio decreases and the width ratio increases as dredging depth ratio increases results in great increase of shape factor and backwater rise by the conveyance reduction at confluence. The regression equation of shape factor with confluence angle, discharge ratio, and dredging depth ratio has been suggested.

Optimization of High Efficiency Single Crystalline Silicon Solar Cell by Using PC1D (PC1D를 이용한 결정질 실리콘 태양전지 최적화)

  • Lee, Yong-Woo;Yi, Young-Seok;Han, Kyu-Min;Yi, Jun-Sin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.195-196
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    • 2008
  • Doping depth, doping concentration, and resistivity of crystalline silicon solar cell are variables which take important portion in cell's efficiency. To get highly efficient solar cell, PC1D is used to calculate $I_{sc}$, $V_{oc}$, and $P_{max}$. Depth factor, peak doping, and base resistivity was used as variables. As a result, the optimized value of emitter peak doping is $1\times10^{19}cm^{-3}$, depth factor is $1{\mu}m$, and base $\rho$ is $ 0.1\Omega$-cm. Under the optimized condition, the solar cell gets efficiency 19.03(%).

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Phenomenological Study on the Purchase Experience of HMR Products in Baby Boom Generation (베이비붐 세대의 HMR 제품 구매경험에 관한 현상학적 연구)

  • Jeong, Seong Ho;Han, Kyung Soo
    • Journal of the FoodService Safety
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    • v.2 no.1
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    • pp.22-29
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    • 2021
  • This research has conducted one-on-one depth interviews targeting baby boomers who are economically active; It seeks to analyze the purchase factor of HMR products to deduct conclusion. The result of the research deducted through depth interviews is as follows. First, baby boomers described HMR products as a reliable meal. Second, baby boomers described HMR products as a cold-hearted meal. Third, baby boomers described HMR products as a habitual meal. Fourth, baby boomers described HMR products as lacking. Fifth, baby boomers thanked to HMR products. The research deducted the conclusion about the HMR products' purchase factor through one-on-one depth interviews. Additionally, the research showed a potential direction for the research and development of HMR products.

Stress intensity factors for periodic edge cracks in a semi-infinite medium with distributed eigenstrain

  • Afsar, A.M.;Ahmed, S.R.
    • Structural Engineering and Mechanics
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    • v.21 no.1
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    • pp.67-82
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    • 2005
  • This study analyzes stress intensity factors for a number of periodic edge cracks in a semiinfinite medium subjected to a far field uniform applied load along with a distribution of eigenstrain. The eigenstrain is considered to be distributed arbitrarily over a region of finite depth extending from the free surface. The cracks are represented by a continuous distribution of edge dislocations. Using the complex potential functions of the edge dislocations, a simple as well as effective method is developed to calculate the stress intensity factor for the edge cracks. The method is employed to obtain the numerical results of the stress intensity factor for different distributions of eigenstrain. Moreover, the effect of crack spacing and the intensity of the normalized eigenstress on the stress intensity factor are investigated in details. The results of the present study reveal that the stress intensity factor of the periodic edge cracks is significantly influenced by the magnitude as well as distribution of the eigenstrain within the finite depth. The eigenstrains that induce compressive stresses at and near the free surface of the semi-infinite medium reduce the stress intensity factor that, in turn, contributes to the toughening of the material.

A Basic Study on Growth Characteristics of the Small Surface Crack in 21/4 Cr-1 Mo Steel (2 1/4 Cr-1Mo강의 작은 표면균열의 성장에 관한 기초적 연구)

  • 서창민;강용구
    • Journal of Ocean Engineering and Technology
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    • v.1 no.1
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    • pp.104-110
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    • 1987
  • Fatigue tests by axial loading (R = 0.05) were carried out to investigate fatigue crack growth characteristics of small surface cracks in 2 1/4 Cr-1 Mo steel at room temperature by using flat specimens with a small artificial pit. All the data of the fatigue crack growth rate obtained in the present test are determined as a function of the stress intensity factor range about a semi-elliptical crack, so that the application of linear fracture mechanics to the surface fatigue crack growth and to the fatigue crack growth into depth, and all the data obtained from tests were discussed in comparison with the data of Type 304 stainless steel and two type of mild steel under the same test conditions. The obtained results are as follows: 1)When the cycle ratios are same, surface fatigue crack length and its depth are almost same and fall within a narrow scatter band in spite of different stress levels. 2)Relations of the surface fatigue crack growth rate (da/dN) and fatigue crack growth rate into depth (db/dN) to its stress intensity factor range ($\Delta K_{Ia}, \Delta K_{Ib}$) can be plotted as a straight line at log-log diagram without dependence of stress level and coincide with the data of part-through crack in various steels.

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Relation Between Wire Sawing-damage and Characteristics of Single Crystalline Silicon Solar-cells (와이어 소잉 데미지 층이 단결정 실리콘 태양전지 셀 특성에 미치는 영향)

  • Kim, Il-Hwan;Park, Jun-Seong;Park, Jea-Gun
    • Current Photovoltaic Research
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    • v.6 no.1
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    • pp.27-30
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    • 2018
  • The dependency of the electrical characteristics of silicon solar-cells on the depth of damaged layer induced by wire-sawing process was investigated. To compare cell efficiency with residual sawing damage, silicon solar-cells were fabricated by using as-sawn wafers having different depth of saw damage without any damaged etching process. The damaged layer induced by wire-sawing process in silicon bulk intensely influenced the value of fill factor on solar cells, degrading fill factor to 57.20%. In addition, the photovoltaic characteristics of solar cells applying texturing process shows that although the initial depth of saw-damage induced by wire-sawing process was different, the value of short-circuit current, fill-factor, and power-conversion-efficiency have an almost same, showing ~17.4% of cell efficiency. It indicated that the degradation of solar-cell efficiency induced by wire-sawing process could be prevented by eliminating all damaged layer through sufficient pyramid-surface texturing process.

Analysis on Failure Critical Depth of Unsaturated Landslide Zone According to the Geological Condition (지질별 불포화토 사면의 붕괴 임계심도 분석)

  • Nam, Koung-Hoon;Kim, Min-Gyu;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
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    • v.25 no.2
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    • pp.299-304
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    • 2015
  • Slope stability analysis of unsaturated soil slopes due to rainfall infiltration is an important issue in evaluating landslide analysis and stability assessment. The purpose of this study is to establish the critical depth considering weathered soil of parent rock and rainfall intensity at main scarp in national landslide. Based on the analytical results, it is found that as rainfall duration and Slope angle increased, the critical depth of gneiss-weathered soil increased from 3.00 m to 3.77 m, the critical depth of granite weathered-soil increased from 1.75 m to 2.40 m, and the critical depth of mudstone-weathered soil increased from 3.00 m to 4.15 m, respectively. The critical depth of granite-weathered soil with low cohesion and high internal friction angle is much lower than those of other soils. It is interestingly shown that a decrease in the safety factor is highly significant, much affected by the slope increase rather than the rainfall intensity.