• Title/Summary/Keyword: Moment coefficient

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Analysis of Lodging Related Characteristics in Rice Plants (벼 도복에 관여하는 형질 분석)

  • 임준택;이홍재;조광석;송동석
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.37 no.1
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    • pp.78-85
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    • 1992
  • This experiment was carried out to investigate the heritabilities, phenotypic correlation, genetic correlation and path-coefficients for desirable characters on the lodging related traits. Characters, that had high relation degree with field lodging degree, were rice-straw length, Wl /P, W/I, Wl /d, L, Wl / A, W/l, P, W $s^2$/ $l^4$ etc. Breaking strength appear negative correlation having an intention to field lodging. The second inertia moment of culm diameter trunk (branch), cross section area, rice-straw thickness and trunk cross section didn't appear negative coefficient with field lodging. It is considered that rice-straw length, leaf dry weight and lodging index, because of high heritability, become selection index of characters for breeding. In direct, indirect effect, and right rice-straw wall thickness appear largest( $P_{7y}$=0.6904), the next is the order of leaf dry weight( $P_{3y}$=0.2848), root dry weight ( $P_{1y}$=0.2658), culm diameter ( $P_{6y}$=-0.2280), and negative relation appear the order of rice-straw length ( $P_{5y}$=-0.9640) and stem dry weight( $P_{2y}$=-0.7072), therefore, the smaller culm length and stem dry weight, the stronger to lodging. to lodging.

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Lateral Behavior of Single Rigid Driven Pile in Non-Homogeneous Sand (비균질 지반에서 항타 관입한 단일 강성말뚝의 수평거동 연구)

  • 김영수;김병탁
    • Journal of the Korean Geotechnical Society
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    • v.15 no.6
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    • pp.167-185
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    • 1999
  • A series of model tests was performed to find the characteristics of lateral behavior of single rigid pile. This paper shows the results of model tests on the lateral behavior of single rigid driven pile in non-homogeneous(two layered) Nak-Dong River sands. The purpose of this paper is to investigate the effect of the ratio of lower layer thickness to embedded pile length, the coefficient ratio of the subgrade reaction and the pile construction conditions(driven & embedded piles) on the characteristics of lateral behavior of single pile. The results of model tests show that the lateral behavior in non-homogeneous soil depends upon drop energy considerably, that is, in the case of H/L=0.75, as the drop energy increases three times the decrease percentage increases about 2.12 times. In the driven pile with non-homogeneous soil of $E_{h1}/E_{h2}=5.56$, the effect of upper layer with large stiffness on the decrease of lateral deflection is remarkably smaller than embedded pile. In non-homogeneous soil, the maximum bending moment of driven pile is in the range of 100 132% in comparison with embedded pile. The reason is that the stiffness of soil around pile increases with drop vibration and so the pile behavior is similar to the flexible pile behavior by means of the increase of relative stiffness of pile, In this paper, the experimental equations for lateral load and H/L on $y_D/y_E \; & \; MBM_D/MBM_E$ are suggested from model tests.

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The Reinforcing Effect of Blade Attached Pile to Support Submerged Breakwater (보강날개로 보강된 수중잠제 지지말뚝의 보강효과 분석)

  • Jeong, Sangseom;Hong, Moonhyun;Ko, Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.4
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    • pp.863-874
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    • 2015
  • The use of pile reinforcement is considered as one of the most promising techniques for improving load carrying capacity of piles in offshore area. In this study, to consider the horizontal and uplift bearing capacity of submerged breakwater bearing pile, exclusive analysis on load-transfer behaviour of pile was conducted. First of all, check the reinforcing effect from the three-dimensional finite element method, and estimate load transfer curve (ground reaction force). Based on these results, the reinforcing effect was quantified by estimating the coefficients of horizontal and uplift reinforcement of reinforced piles. Load transfer function with consideration of the reinforcing effect was proposed from estimated coefficients. A comparison of the analysis using the proposed load transfer function with three-dimensional finite element analysis has resulted that the proposed load transfer function is displaying good accuracy of predicting behavior of the load transfer between the pile and soil reinforcement. Interpretation of the submerged structure by applying a load transfer function considering the reinforcing effect, has shown that the reinforced pile's shear, bending moment and displacement are less than that of non-reinforced piles, while the subgrade reaction modulus arises greater. Thus, it is expected to be relatively cost effective in terms of design.

Review of Steel ratio Specifications in Korean Highway Bridge Design Code (Limit States Design) for the Design of RC Flexural Members (철근콘크리트 휨부재 설계를 위한 도로교설계기준(한계상태설계법)의 철근비 규정 검토)

  • Lee, Ki-Yeol;Kim, Woo;Lee, Jun-Seok
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.2
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    • pp.277-287
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    • 2017
  • This paper describes the specifications on balanced steel ratio and maximum reinforcement for the design of RC flexural members by the Korean Highway Bridge Design Code based on limit states design. The Korean Highway Bridge Design Code (Limit States Design) is not provide for the balanced steel ratio specification for the calculation of required steel area of RC flexural members design. The maximum steel area limited the depth of the neutral axis at the ultimate limit states after redistribution of the moment, and also recommended the maximum steel area should not exceed 4 percent of the cross sectional area. However, from the maximum neutral axis depth provisions should increase the cross section is calculated to be less the maximum reinforcement area, and according to the 4% of the cross sectional area of the concrete, the tensile strain of the reinforcement is calculated to be greater than double the yielding strain, so can not guarantee a ductile behavior. This study developed a balanced reinforcement ratio that is basis for the required reinforcement calculation for tension-controlled RC flexural members design in the ultimate limit states verification provisons and material properties and applied the ultimate strain of the concrete compressive strength with a simple formular to be applied to design practice induced. And assumed the minimum allowable tensile strain of reinforcement double the yielding strain, and applying correction coefficient up to the ratio of maximum neutral axis depth, proposed maximum steel ratio that can be applied irrespective of the reinforcement yield strength and concrete compressive strength.

The Relationship between Mathematically Gifted Elementary Students' Math Creative Problem Solving Ability and Metacognition (초등수학영재의 수학 창의적 문제해결력과 메타인지와의 관계)

  • Shin, Seung Yoon;Ryu, Sung Rim
    • Education of Primary School Mathematics
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    • v.17 no.2
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    • pp.95-111
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    • 2014
  • The purpose of this study is to determine the relationship between metacognition and math creative problem solving ability. Specific research questions set up according to the purpose of this study are as follows. First, what relation does metacognition has with creative math problem-solving ability of mathematically gifted elementary students? Second, how does each component of metacognition (i.e. metacognitive knowledge, metacognitive regulation, metacognitive experiences) influences the math creative problem solving ability of mathematically gifted elementary students? The present study was conducted with a total of 80 fifth grade mathematically gifted elementary students. For assessment tools, the study used the Math Creative Problem Solving Ability Test and the Metacognition Test. Analyses of collected data involved descriptive statistics, computation of Pearson's product moment correlation coefficient, and multiple regression analysis by using the SPSS Statistics 20. The findings from the study were as follows. First, a great deal of variability between individuals was found in math creative problem solving ability and metacognition even within the group of mathematically gifted elementary students. Second, significant correlation was found between math creative problem solving ability and metacognition. Third, according to multiple regression analysis of math creative problem solving ability by component of metacognition, it was found that metacognitive knowledge is the metacognitive component that relatively has the greatest effect on overall math creative problem-solving ability. Fourth, results indicated that metacognitive knowledge has the greatest effect on fluency and originality among subelements of math creative problem solving ability, while metacognitive regulation has the greatest effect on flexibility. It was found that metacognitive experiences relatively has little effect on math creative problem solving ability. This findings suggests the possibility of metacognitive approach in math gifted curricula and programs for cultivating mathematically gifted students' math creative problem-solving ability.

Reliability Analysis of Caisson Type Quaywall (안벽구조물의 신뢰성 해석)

  • Yoon, Gil-Lim;Kim, Dong-Hywan;Kim, Hong-Yeon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.20 no.5
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    • pp.498-509
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    • 2008
  • Reliability analyses of Level I, II and III for bearing capacity, overturning and sliding of quaywall are carried out to investigate their safety levels depending upon its failure modes, and sensitivity analyses of each design variable are performed to find their effects on safety levels of quaywall. Reliability indices was 1.416 for both level II and III for case study I, and with 2.201 and 1.880, respectively, for the case study II at the critical loading conditions. Thus we were able to know that Level II (FORM) approach is good enough to use in practical design. Generally, it was found that probabilities of failure of quaywall were higher for sliding and bearing capacity failure modes and lower for overturning failure mode. From sensitivity analyses, the most influential design variables to reliability index of quaywall were coefficient of friction, residual water pressure and resistance moment for the sliding, overturning and bearing capacity failure modes, respectively. Especially, the sensitivity of reliability index due to inertial force and dynamic water pressures, which include a large COV when earthquake occurs, did not change greatly.

Digital Camera Identification Based on Interpolation Pattern Used Lens Distortion Correction (디지털 카메라의 렌즈 왜곡 보정에 사용된 보간 패턴 추출을 통한 카메라 식별 방법)

  • Hwang, Min-Gu;Kim, Dong-Min;Har, Dong-Hwan
    • Journal of Internet Computing and Services
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    • v.13 no.3
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    • pp.49-59
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    • 2012
  • Throughout developing digital technology, reproduction of image is growing better day by day. And at the same time, diverse image editing softwares are developed to manage images easily. In the process of editing images, those programs could delete or modify EXIF files which have the original image information; therefore images without the origin source are widely spread on the web site after editing. This matter could affect analysis of images due to the distortion of originality. Especially in the court of law, the source of evidence should be expressed clearly; therefore digital image EXIF file without deletion or distortion could not be the objective evidence. In this research, we try to trace the identification of a digital camera in order to solve digital images originality, and also we focus on lens distortion correction algorism which is used in digital image processing. Lens distortion correction uses mapping algorism, and at this moment it also uses interpolation algorism to prevent aliasing artifact and reconstruction artifact. At this point interpolation shows the similar mapping pattern; therefore we want to find out the interpolation evidence. We propose a minimum filter algorism in order to detect interpolation pattern and adjust the same minimum filter coefficient in two areas; one has interpolation and the second has no interpolation. Throughout DFT, we confirm frequency character between each area. Based on this result, we make the final detection map by using differences between two areas. In other words, thereby the area which has the interpolation caused by mapping is adjusted using minimum filter for detection algorism; the second area which has no interpolation tends to different frequency character.

Wind loads and load-effects of large scale wind turbine tower with different halt positions of blade

  • Ke, Shitang;Yu, Wei;Wang, Tongguang;Zhao, Lin;Ge, Yaojun
    • Wind and Structures
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    • v.23 no.6
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    • pp.559-575
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    • 2016
  • In order to investigate the influence of different blade positions on aerodynamic load and wind loads and load-effects of large scale wind turbine tower under the halt state, we take a certain 3 MW large scale horizontal axis three-blade wind turbine as the example for analysis. First of all, numerical simulation was conducted for wind turbine flow field and aerodynamic characteristics under different halt states (8 calculating conditions in total) based on LES (large eddy simulation) method. The influence of different halt states on the average and fluctuating wind pressure coefficients of turbine tower surface, total lift force and resistance coefficient, circular flow and wake flow characteristics was compared and analysed. Then on this basis, the time-domain analysis of wind loads and load-effects was performed for the wind turbine tower structure under different halt states by making use of the finite element method. The main conclusions of this paper are as follows: The halt positions of wind blade could have a big impact on tower circular flow and aerodynamic distribution, in which Condition 5 is the most unfavourable while Condition 1 is the most beneficial condition. The wind loads and load-effects of disturbed region of tower is obviously affected by different halt positions of wind blades, especially the large fluctuating displacement mean square deviation at both windward and leeward sides, among which the maximum response occurs in $350^{\circ}$ to the tower top under Condition 8; the maximum bending moment of tower bottom occurs in $330^{\circ}$ under Condition 2. The extreme displacement of blade top all exceeds 2.5 m under Condition 5, and the maximum value of windward displacement response for the tip of Blade 3 under Condition 8 could reach 3.35 m. All these results indicate that the influence of halt positions of different blades should be taken into consideration carefully when making wind-resistance design for large scale wind turbine tower.

A Study of Anxiety Scale Applied to Patients with Anxiety Disorder (불안 환자에 대한 불안척도의 연구)

  • Lee, Jung-Hoon;Park, Byung-Tak
    • Journal of Yeungnam Medical Science
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    • v.9 no.1
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    • pp.156-166
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    • 1992
  • The authors studied anxiety, using Zung's self-rating anxiety scale(SAS), in the subjects of 127 male and 38 female patients with anxiety disorder. The authors investigated 165 patients in Yeungnam university hospital from January, 1987 to June, 1991. In order to analyze the data on anxiety scores Pearson's product moment coefficient correlation method and factor analysis were carried out by SPSS/PC+ program. The results were as follows : There was significant difference in the mean averages of total anxiety scores among patients with anxiety, disorder and male and female college freshmen: patients with anxiety disorder scored $42.40{\pm}7.74$, male students scored $32.91{\pm}5.70$, female students scored $34.48{\pm}6.00$. The anxiety scores relating to the items of body aches & pains, fatigue, anxiousness, panic, and urinary frequency were relatively high in patients with anxiety disorder. The anxiety scores on the items of restlessness, apprehension, dyspnea, sweating, and insomnia were relatively low in patients with anxiety disorder. Twenty-nine anxiety disorder group(17.5%) showed significantly high anxiety scores of 50 or over. The inter-rater reliability of Zung's self-rating anxiety scale was 0.71.

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The Impact of SWAL-QOL on Overall Quality of Life in Normal Elderly People: Focusing on Jeonbuk Province (정상노인의 삼킴관련 삶의 질(SWAL-QOL)이 노인의 전반적인 삶의 질에 미치는 영향-전북 지역을 중심으로-)

  • Kim, Se-Yun
    • The Journal of the Korea Contents Association
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    • v.14 no.6
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    • pp.288-297
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    • 2014
  • The purpose of this study was to investigate the quality of life related to swallowing through Swallowing-Quality Of Life(SWAL-QOL) and examine the impact of SWAL-QOL on overall quality of life measured by Short-Form Health Survey(SF-36) and Geriatric Quality of Life(GQOL). For this purpose, the SWAL-QOL, SF-36 and GQOL have been conducted on 140 old people who were all over 60 years of age and physically and mentally normal. The collected data have been analyzed using a Windows SPSS 21.0 program. The results show that the SWAL-QOL are significant differences according to age(F=7.76, p<.01) and aspiration(t=-4.44, p<.01) and aspiration is ouly factor affecting the SW AL-QOL in elderly people. There are significant correlations between SF-36, GQOL and SW AL-QOL and the pearson product moment correlation coefficient is .39(p<.01) and .33(p<.01) respectively. The SWAL-QOL can predict approximately 36% and 25% of quality of life measured by SF-36 and GQOL. Therefore, this result will be able to utilize as basic data to improvement of quality of life related swallowing and overall quality of life related to health in normal elderly people.