• Title/Summary/Keyword: thinness ratio

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Strength and behaviour of bamboo reinforced concrete wall panels under two way in-plane action

  • Ganesan, N.;Indira, P.V.;Himasree, P.R.
    • Advances in concrete construction
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    • v.6 no.1
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    • pp.1-13
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    • 2018
  • An experimental investigation has been carried out on the use of an environmentally sustainable material, bamboo, in the construction of precast concrete structural wall panels. The strength and behaviour of three prototype bamboo reinforced concrete wall panel specimens under two-way in-plane action was studied. The specimens with varying aspect ratio and thinness ratio were tested to fail under a uniformly distributed in-plane load applied at an eccentricity of t/6. The aspect ratio of the specimens considered includes 1.667, 1.818 and 2 and the thinness ratio includes 12.5, 13.75 and 15. The influence of aspect ratio and thinness ratio of bamboo reinforced concrete wall panels, on its strength and behaviour was discussed. Varnished and sand blasted bamboo splints of 20 mm width and thickness varying from 8 to 15 mm were used as reinforcement in concrete. Based on the study, an empirical equation was developed considering the geometrical parameters of bamboo reinforced concrete wall panels for predicting its ultimate strength under two way in-plane action.

Crack Damages in Exterior Wall Structures of Korean High-Rise Apartment Buildings Based on Nonlinear Finite Element Analysis (비선형 유한요소해석 기반 국내 고층아파트 외벽구조의 균열손상 특성 분석)

  • Kim, Sung Hyun;Mo, Sang Yeong;Kim, Si Hyun;Choi, Kyoung Kyu;Kang, Su Min
    • Journal of the Earthquake Engineering Society of Korea
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    • v.28 no.1
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    • pp.47-57
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    • 2024
  • Recently, in newly constructed apartment buildings, the exterior wall structures have been characterized by thinness, having various openings, and a significantly low reinforcement ratio. In this study, a nonlinear finite element analysis was performed to investigate the crack damage characteristics of the exterior wall structure. The limited analysis models for a 10-story exterior wall were constructed based on the prototype apartment building, and nonlinear static analysis (push-over analysis) was performed. Based on the finite element (FE) analysis model, the parametric study was conducted to investigate the effects of various design parameters on the strength and crack width of the exterior walls. As the parameters, the vertical reinforcement ratio and horizontal reinforcement ratio of the wall, as well as the uniformly distributed longitudinal reinforcement ratio and shear reinforcement ratio of the connection beam, were addressed. The analysis results showed that the strength and deformation capacity of the prototype exterior walls were limited by the failure of the connection beam prior to the flexural yielding of the walls. Thus, the increase of wall reinforcement limitedly affected the failure modes, peak strengths, and crack damages. On the other hand, when the reinforcement ratio of the connection beams was increased, the peak strength was increased due to the increase in the load-carrying capacity of the connection beams. Further, the crack damage index decreased as the reinforcement ratio of the connection beam increased. In particular, it was more effective to increase the uniformly distributed longitudinal reinforcement ratio in the connection beams to decrease the crack damage of the coupling beams, regardless of the type of the prototype exterior walls.

Inelastic general instability of ring-stiffened circular cylinders and cones under uniform external pressure

  • Ross, C.T.F.
    • Structural Engineering and Mechanics
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    • v.5 no.2
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    • pp.193-207
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    • 1997
  • Experimental tests are described on three ring stiffened machined circular cylinders and three ring stiffened machined circular cones, which were tested to destruction under uniform external pressure. All six vessels failed by inelastic general instability. The experiments showed that the vessels initially deformed plastically at mid-bay in the circumferential direction, and this caused the circumferential tangent modulus to become much less than the elastic Young's modulus, causing the vessels to fail through plastic general instability at pressures much less than that predicted by elastic theory. Based on a thinness ratio, two semi-empirical design charts are provided, which are intended to be used for design purposes in conjunction with the finite element method and a plastic reduction factor.

Evaluation of static response in stress-ribbon concrete pedestrian bridges

  • Stavridis, Leonidas T.
    • Structural Engineering and Mechanics
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    • v.34 no.2
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    • pp.213-229
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    • 2010
  • An analytical method is proposed for the evaluation of the static response of a prestresse-dribbon concrete pedestrian bridge, which may also be applied for the roofing of large areas. On the basis of an established analogy with a suspension bridge system, a procedure is presented for the prestresse-dribbon direct analysis, leading to the introduction of two dimensionless parameters as governing factors of the design, namely the thinness and the prestressing steel ratio. The exposed procedure, applied by a simple computer program, allows a quick evaluation of the response and permits the investigation of the influence of the aforementioned parameters on it, by means of comprehensive diagrams. The presented diagrams may be directly used for the preliminary design of a pedestrian bridge of this type, for the whole practical range of span lengths. A design example is also included, showing the applicability of the proposed procedure.

Weight Concerns and Eating Patterns of College Women (여대생의 체중조절에 대한 과심도와 섭식행동)

  • 이영미
    • Journal of the Korean Home Economics Association
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    • v.32 no.2
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    • pp.193-206
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    • 1994
  • Thinness has become a symbol for beauty acceptance and competence for women in our society especially for young college women. Relatively little is known about characteristics of women who are dissatisfied with their shape or weight and who are interested in performing weight control program. Four hundred college women in Seoul and Kyunggi-Do area were surveyed from November to December 1992 to investigate the relationship between the concern about weight control and various aspects of food related behaviors. The purpose of this research was to investigate the relationship between the weight concerns of college women and their aspects of several eating behaviors. Self-developed questionnaire was used after validity test. The results were as follows: 1) The average height weight and BMI value of subjects were 160$\pm$4.5cm 51.02kg and 19.86$\pm$4.5 respectively. 2) The 49% of subjects were highly concerned about weight control(high interest group) and 39% were moderate concerned(moderate interest group). 3) The average BMI and weight change per year were significantly higher in the high interest group than other groups. 4) The score of nutrition knowledge was also higher in the high interest group, 5) There were no significant differences among groups in the meal frequencies. and amount of nutrients intake. 6) The signs of eating trouble were found in subjects 59.0% of subjects felt feareness about weight gain after consumption of large amount of food. 7) The ratio of CPF was 64:14:22 and nutrient adquacy ratio(NAR) of energy was 0.94 NAR of Fe was 0.84 the other NAR of nutrient over 1.0.

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A Study on Orchestration in "Battle for The Glory" out of the Background Music in the Animation "Dragon Quest IV" (애니메이션 "드래곤 퀘스트 IV"의 배경음악 중 "Battle for The Glory"에 나타난 관현악법 연구)

  • Jung, Kil
    • Cartoon and Animation Studies
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    • s.39
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    • pp.321-348
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    • 2015
  • The purpose of this study was to find a system and a progression principle in orchestral piece based on the outcome after comparatively analyzing the orchestral operation technique in "Battle for The Glory" out of the background music in the animation "Dragon Quest IV" by Koichi Sugiyama(1931~), who is a leading runner of Japan's animation music, based on functional parts daccord & Instrumentation Pattern, Rhythm Pattern, Voicing Pattern, and harmonic ratio by progression section devised by the writer. As a result, first, five themes in this music have specific instrumentation pattern, respectively. In a passage that is shown exposition, reprise, and representation in theme, the unity was emphasized by maintaining the same instrumentation pattern. On the contrary to this, a passage of being suggested new theme is being used the exchange method and addition & subtraction in musical instrument in order to strengthen diversity. Second, the voicing pattern is forming the vertical contrasting relationship of "thinness-thickness" on the whole. However, the diversity is being intensified that is changed into the structure of "thickness-thinness" in the third theme and of "thinness-thickness" that has two melodies in the fourth theme. Third, the rhythm pattern is forming the vertical contrasting relationship of "big-small" on the whole. However, the fifth theme is being given diversity with being changed into the structure of "small-big." Fourth, the harmony by progression section from the horizontal perspective is shown to be high in the proportion of unity in the section of being repeated and represented the theme and to be high in the proportion of diversity in the section of being suggested new theme. In this study, the balanced orchestral operation technique through the operation technique, which was used in this work, is what extracts the relationship of diverse proportions in the horizontal progression section based on the technique of vertical perspective. In this aspect, this analytical study is desired to be positioned as a new paradigm in establishing a theoretical system and an educational method in orchestration.

Attenuating Development of Cardiovascular Hypertrophy with Hydrolysate of Chicken Leg Bone Protein in Spontaneously Hypertensive Rats

  • Cheng, Fu-Yuan;Wan, Tien-Chun;Liu, Yu-Tse;Lai, Kung-Ming;Lin, Liang-Chuan;Sakata, Ryoichi
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.5
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    • pp.732-737
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    • 2008
  • This study developed a natural ingredient as a functional food possessing properties of attenuation of hypertension and cardiovascular hypertrophy. In a previous study hydrolysates obtained from chicken leg bone protein using Alcalase strongly inhibited angiotensin I converting enzyme (ACE) in vitro. In particular, hydrolysate (A4H) from four hours of incubation exhibited the highest ACE inhibitory activity (IC50 = 0.545 mg/ml). A4H was selected as a potent ACE inhibitor and orally administrated to spontaneously hypertensive rats (SHR) for eight weeks to investigate attenuating effects on age-related development of hypertension and cardiovascular hypertrophy. Results showed that treatment with A4H of SHRs attenuated the development of hypertension as effectively as the clinical antihypertensive drug captopril. Moreover, a significantly lower heart to body weight ratio and thinness of coronary arterial wall was observed in SHRs that had been treated with A4H or captopril. The results suggest that A4H can be utilized in developing an ACE inhibitor as a potential ingredient of functional foods to alleviate hypertension and cardiovascular hypertrophy.

Eating Traits and General Psychopathology of Korean Males Who Show High Score on the Korean Version of Eating Attitudes Test-26 (한국판(韓國版) 식사태도(食事態度) 검사(檢査)-26에서 고득점(高得點)을 보인 한국(韓國) 일반(一般) 남성군(男性群)의 식사특성(食事特性)과 일반정신병리(一般精神病理))

  • Han, Ki-Seok;Lee, Young-Ho;Rhee, Min-Kyu;Park, Se-Hyun;Sohn, Chang-Ho;Chung, Young-Cho;Hong, Sung-Kook;Lee, Byung-Kwan;Chang, Phi-Lip;Yoon, A-Rhee
    • Korean Journal of Psychosomatic Medicine
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    • v.7 no.1
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    • pp.87-102
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    • 1999
  • Objectives : The purposes of this study were to estimate the prevalence rate of eating disorders in Korean males and to clarify their characteristics in sociodemograhic data, the eating traits, and general psychopathology through the comparison with those of female high scored group on the Korean version of Eating Attitudes Test-26(KEAT-26). Methods : Using a multi-stage questionnaire sampling method including area sampling, proportionated stratified sampling, and quota sampling, we surveyed a total of 4,400 Korean adults over 18 in a nationwide area(9 kus, 10 middle or small cities, and 17 kuns), obtaining usable responses on 3,896. Of the 3,062 subjects(1249 males and 1813 females) who were available for analysis, we ascertained 52 males and 208 females who had high score($\geq$ cutoff point 21) on the KEAT-26. Results : 1) The proportion of this high score group was 1.7% in male and 6.8% in female with a sex ratio(male versus female) of 1 : 4. 2) The mean age was higher in the male group than in the female group, although it was not statistically significant(p=0.0514). Mean Body Mass Index(BMI) of the male group was significantly higher than that of female group, and the number of male subjects with below 20 of BMI was also significantly lower than in the female group. 3) There were no significant difference in past history of physical illness between two groups. However, frequency of smoking and alcohol use, and mean amount of alcohol consumption per month were significantly higher in the male group than in the female group. There were no significant differences between the two groups on various socio-demographic correlates such as economic status, total duration of education, number of family, marital status, religious status, and area of residence, but the exception of being occupational status. 4) The 'Eating Habits Scale' score and score of 'preference for vegetables and fish, and dislike for sweet-tasting food' of the male group were significantly lower than those of the female group. Although there was no significant difference between the two groups in total scores of the KEAT-26, the mean score on 'pursuit of thinness' subscale was higher in the female group than in the male group, while scores of 'food preoccupation' and 'self-control' subscales were higher in the male group than in the female group. 5) Scores on 'psychoticism' was significantly higher in the male group than in the female group, although there were no significant differences between the two groups on 'locus of control for weight', 'depression' and 'hypochondriasis'. Conclusion : These results support a possibility of a high prevalence of eating disorders in Korean males. These results suggest that eating related characteristics of high scorer on the EAT are different by sex in spite of the same high score on the EAT, and also suggest that male patients with eating disorders have more serious personality pathology than female patients with eating disorders.

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