• Title/Summary/Keyword: strengths

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Evaluation of Slant Shear Strength of Recycled Asphalt Mixture with Different Tack Coat Applications (Tack Coat 使用條件에 따른 再活用 아스팔트 混合物의 附着剪斷 性能評價)

  • 김낙석
    • Resources Recycling
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    • v.10 no.1
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    • pp.32-41
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    • 2001
  • Bond shear strengths of recycled asphalt concrete were evaluated under different tack coat applications. Regardless of the new and old mixtures, the bond shear strengths at $30^{\circ}C$ were increased by 10-20% than those at 1$0^{\circ}C$. The bond shear strengths of recycled asphalt concrete without tack coat showed very low ones. These are the main reasons for the frequent longitudinal interface crack in the field. The effect of tack coat curing time on bond shear strengths was inferior to the tack coat construction temperature.

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A Study on the Strengths of Polyurethane Morthar Cured under Low Temperature Condition (저온양생한 폴리우레탄 모르타르의 강도특성에 관한 연구)

  • 오종석;정효석;박홍신;조영국;소양섭
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.04a
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    • pp.337-342
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    • 1999
  • The Purpose of this study is to evaluate the strength characteristics of polyurethane(PUR) mortar cured under low temperature condition. PUR mortars are prepared with various catalyst content, methylene chloride(MC) content as a viscosity reducing agent, and curing age at low temperature condition of $0^{\circ}C$, -5$^{\circ}C$ and -1$0^{\circ}C$, tested for working life, compressive and flexural strengths. From the test results, the catalyst and MC contents affect the degree of hardening and blowing of PUR mortar. Strengths increase with an increasing catalyst content at low temperature. Flexural and compressive strength of PUR mortar are about 177kgf/$\textrm{cm}^2$ and 490kgf/$\textrm{cm}^2$ respectively at curing temperature of -1$0^{\circ}C$ with catalyst content of 0.4%. Therefore, it is apparent that this PUR mortars have a sufficient strengths for repair of concrete structures.

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Pull-out Strengths of GFRP-Concrete Bond Exposed to Applied Environmental Conditions

  • Kabir, Muhammad Ikramul;Samali, Bijan;Shrestha, Rijun
    • International Journal of Concrete Structures and Materials
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    • v.11 no.1
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    • pp.69-84
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    • 2017
  • This paper presents results of an experimental investigation on the behaviour of bond between external glass fibre reinforced polymer reinforcement and concrete exposed to three different environmental conditions, namely, temperature cycles, wet-dry cycles and outdoor environment separately for extended durations. Single shear tests (pull-out test) were conducted to investigate bond strengths (pull-out strengths) of control (unexposed) and exposed specimens. Effect of the exposure conditions on the compressive strength of concrete were also investigated separately to understand the effect of changing concrete compressive strength on the pull-out strength. Based on the comparison of experimental results of exposed specimens to control specimens in terms of bond strengths, failure modes and strain profiles, the most significant degradation of pull-out strength was observed in specimens exposed to outdoor environment, whereas temperature cycles did not cause any deterioration of strength.

A Study on University Student's Implement of Manners and their Strengths of Family Life (대학생의 생활예절수행과 가정생활건강성 연구)

  • Lee Hong Hwa;Lee Jeong Woo
    • Journal of Family Resource Management and Policy Review
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    • v.9 no.2
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    • pp.23-40
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    • 2005
  • Manners is important factor of healthy family life and helps to form diverse human relationship properly at university and society. The main purpose of this research was to emphasize the importance of manners by examining university student's conduct of manners which is basically demanded for harmonious social life and progressive human relationship. First, the health level of the conduct of the subject students appeared to exceed the average. Second, as a result of examining conduct of manners and strengths of healthy family life, it has been analyzed that humanitarian value, number of siblings and realization of the significance of the healthy family life are serious variables. Third, it has been analyzed that the higher the level of university student's conduct of the manner of family life, the higher the level of strengths of healthy family life.

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Strengths and Non-destruction Properties of Super Flow Concrete Using Recycled Coarse Aggregate (재생굵은골재를 사용한 초유동 콘크리트의 강도 및 비파괴 특성)

  • Sung, Chan-Yong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.47 no.1
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    • pp.25-32
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    • 2005
  • This study was performed to evaluate strengths and non-destruction properties of super flow concrete using recycled coarse aggregate. At the curing age of 28 days, the compressive strength was 22.7-37.5 MPa, the splitting tensile strength was $2.65\~3.73$ MPa, the flexural strength was $5.78\~6.86$ MPa, the ultrasonic pulse velocity was $3,103\~3,480$ mis, the dynamic modulus of elasticity was $3.401{\times}104\~4.521{\times}104$MPa, respectively. The strengths, ultrasonic pulse velocity and dynamic modulus of elasticity of super flow concrete were decreased with increasing the content of recycled coarse aggregate. The super flow concretes using recycled coarse aggregate were improved by substitution in the range of less than the fly ash content 30010 and recycled coarse aggregate content $75\%$.

Nominal axial and flexural strengths of high-strength concrete columns

  • Al-Kamal, Mustafa Kamal
    • Computers and Concrete
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    • v.24 no.1
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    • pp.85-94
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    • 2019
  • The ACI building code is allowing for higher strength reinforcement and concrete compressive strengths. The nominal strength of high-strength concrete columns is over predicted by the current ACI 318 rectangular stress block and is increasingly unconservative as higher strength materials are used. Calibration of a rectangular stress block to address this condition leads to increased computational complexity. A triangular stress block, derived from the general shape of the stress-strain curve for high-strength concrete, provides a superior solution. The nominal flexural and axial strengths of 150 high-strength concrete columns tests are calculated using the proposed stress distribution and compared with the predicted strength using various design codes and proposals of other researchers. The proposed triangular stress model provides similar level of accuracy and conservativeness and is easily incorporated into current codes.

Personal Strengths Knowledge Is the Key to Employability: Implications for Library and Information Science and Career Development Education for Its Students (취업력 제고의 관건으로서 개인강점 지식 - 문헌정보학과와 사서의 경력개발교육에 주는 의미 -)

  • Cho, Byung-Ju;Choi, Jung-Hee;Oh, Dong-Geun
    • Journal of Korean Library and Information Science Society
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    • v.40 no.4
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    • pp.243-259
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    • 2009
  • This study introduces strengths theory, a core subject of career development and job-getting, and discusses about the factors of strengths(namely talents, knowledge and skills), the processes of strengths personalization, and generating employability. It searches for opportunities to apply the concept of employability to the field of Library and Information Science now thrown under hard pressure from information and communication technology. Employability is defined here as competence to make oneself employable as needed by discovering or creating work opportunities using one's own tested personalized strengths. Employability is a package of systematically organized information about the essential abilities and productive personalities of a person, and it is essential to be duly cognitive of one's employability if one seriously intends to succeed in jobs and career. Since generation of employability heavily involves complex processes of information and knowledge-making, expertise from LIS, particularly from areas of personal information management(PIM) and personal knowledge management(PKM), is expected to help for process facilitation.

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A Study of Different Character Strengths in the Sasang Constitution (사상체질에 따른 성격강점 차이연구)

  • Park, Hyuncheol;Yu, Gyung;Kim, Lakhyung
    • Journal of Oriental Neuropsychiatry
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    • v.28 no.1
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    • pp.39-47
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    • 2017
  • Objectives: The purpose of this study is to investigate the Sasang Constitution character strength of university students. Methods: One hundred fifty students of Woosuk University participated in this study. Their majors were Korean medicine, nursing science, and pharmacy. Their Sasang Constitutional types were determined using the results of a Two Step Questionnaire for Sasang Constitution Diagnosis (TS-QSCD). The subjects were also tested by a Characteristic Strength Test (CST). The Character Strength test scores were compared to the different Sasang Constitutions using analysis of variances (ANOVA). Also, the five Signature Strengths presented to the subjects were measured as a percentage within Sasang Constitution Groups, and compared to the different Sasang Constitutions. Results and Conclusions: 1. In CST score: Soyangin were significantly higher than Taeeumin in creativity, curiosity, love, social intelligence, vitality, leadership, appreciation of beauty and excellence, and humor. Also, Soyangin was significantly higher than Soeumin in wisdom, kindness, bravery, and authenticity. 2. In CST score: Taeeumin were significantly higher than Soyangin in modesty. Taeeumin and Soeumin were significantly higher than Soyangin in prudence. 3. In the five signature strength analysis: Extrovert character strengths such as curiosity, vitality, social intelligence, bravery, and leadership, were higher in Soyangin. On the other hand, Introvert character strengths such as modesty, prudence, and self-regulation, were higher in Taeeumin and Soeumin. 4. In the five signature strength analysis: The signature strengths of Soyangin and Soeumin indicated a biased distribution. The signature strengths of Taeeumin indicated an even distribution.

Push-out bond strengths of fiber-reinforced composite posts with various resin cements according to the root level

  • Chang, Hoon-Sang;Noh, Young-Sin;Lee, Yoon;Min, Kyung-San;Bae, Ji-Myung
    • The Journal of Advanced Prosthodontics
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    • v.5 no.3
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    • pp.278-286
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    • 2013
  • PURPOSE. The aim of this study was to determine whether the push-out bond strengths between the radicular dentin and fiber reinforced-composite (FRC) posts with various resin cements decreased or not, according to the coronal, middle or apical level of the root. MATERIALS AND METHODS. FRC posts were cemented with one of five resin cement groups (RelyX Unicem: Uni, Contax with activator & LuxaCore-Dual: LuA, Contax & LuxaCore-Dual: Lu, Panavia F 2.0: PA, Super-Bond C&B: SB) into extracted human mandibular premolars. The roots were sliced into discs at the coronal, middle and apical levels. Push-out bond strength tests were performed with a universal testing machine at a crosshead speed of 0.5 mm/min, and the failure aspect was analyzed. RESULTS. There were no significant differences (P>.05) in the bond strengths of the different resin cements at the coronal level, but there were significant differences in the bond strengths at the middle and apical levels (P<.05). Only the Uni and LuA cements did not show any significant decrease in their bond strengths at all the root levels (P>.05); all other groups had a significant decrease in bond strength at the middle or apical level (P<.05). The failure aspect was dominantly cohesive at the coronal level of all resin cements (P<.05), whereas it was dominantly adhesive at the apical level. CONCLUSION. All resin cement groups showed decreases in bond strengths at the middle or apical level except LuA and Uni.

The Relationship between Family Concept and Family Strengths Perceived by College Students (대학생들이 인식하는 가족개념과 가족건강성의 관계)

  • Park, Su-Sun
    • Journal of Family Resource Management and Policy Review
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    • v.14 no.1
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    • pp.37-55
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    • 2010
  • The purpose of this study was to determine the factors affecting family strength and therewith, suggest some strategies to improve family strength and welfare. For this purpose, the researcher sampled 208 college students and surveyed them for their perceptions of the concept of family and family strengths. The results of this study can be summarized as follows. First, as a result of surveying the subjects on their perception of the concept of family, it was found that almost all of them (99%) perceived that 'a family consists of a couple and their children' (item 1). The other items regarding the concept of family chosen by the majority of subjects were 'a couple and adopted child' (item 3 & item 17), 'a remarried couple and their children' (item 9), 'a single parent and children' (item 2), 'a three-generation family; couple, widowed daughter and granddaughter' (item 4), 'three sisters' (item 7), 'an unmarried woman living with a son born from a sperm bank' (item 19), 'a separated couple with no child' (item 13), 'cousins living together' (item 11), 'a divorced man and his girlfriend with child' (item 15) and 'homosexual family' (item 8). Second, as a result of assessing subjects' needs for family functions and their efforts for family strengths, it was found that the family functions for family members scored higher than those for the society, and that subjects' efforts for the family functions conducive to both their family members and society scored lower than their needs for the family functions. Third, subjects' needs and efforts for family functions were positively correlated with family strengths. Namely, family functions were closely related with family strengths.

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