• Advances in concrete construction
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• 제16권5호
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• pp.269-276
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• 2023

In order to study the effect of rubber particle size and admixture on the frost resistance of self-compacting concrete, three self-compacting concrete specimens with equal volume replacement of fine aggregate by rubber particles of different particle sizes were prepared, while conventional self-compacting concrete was made as a comparison specimen. The degradation law of rubber aggregate self-compacted concrete under freeze-thaw cycles was investigated by fast-freezing method test. The results show that the rubber aggregate has some influence on the mechanical properties and freeze-thaw durability of the self-compacting concrete. With the increase of rubber aggregate, the compressive strength of self-compacting concrete gradually decreases, and the smaller the rubber aggregate particle size is, the smaller the effect on the compressive strength of the matrix; rubber aggregate can improve the frost resistance of self-compacting concrete, and the smaller the rubber particle size is, the more obvious the effect on the improvement of the frost resistance of the matrix under the same dosage. Through the research of this paper, it is recommended to use 60~80 purpose rubber aggregate and the substitution rate of 10% is chosen as the best effect.

• 부모자녀건강학회지
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• 제4권2호
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• pp.16-31
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• 2002

This study was done in order to analyze the relationship of gender identity, self-esteem, self-efficacy, hardiness, and health promotion behavior in the College Women. The subjects were 275 students from a college in Kyungbuk. The instruments used for this study were made of general characteristics(6 items), gender identity(1 item), self-esteem(10 item), self-efficacy(13 items), hardiness(38 items) and health promoting behaviors(40 items). The data were analyzed by SPSS/$PC^+$ program using descriptive statistics, Pearson's Correlation Coefficient and Multiple Stepwise Regression. The results of this study were as follows. 1. The Mean score of gender identity, self-esteem, self-efficacy, hardiness, and health promotion behavior were as follows. 1) The mean score of the health promoting behavior was 2.24. Among the subcategories, the highest score was interpersonal support(2.91), self-actualization (2.85), and the lowest score was health responsibility(1.62). 2) The mean score of the gender identity was 2.04. 3) The mean score of the self-esteem was 2.85. 4) The mean score of the self-efficacy was 6.50. 5) The mean score of the hardiness was 2.83. 2. Correlations of gender identity, self-esteem, self-efficacy, hardiness, and health promotion behavior were as follows. 1) Gender identity was positively correlated with self-esteem(r=-.287, p=.0000), self-efficacy(r=-.226, p=.0000), hardiness(r=.237, p=.0000), health promotion behavior(r=-.236, p=.0000). 2) Self-esteem was positively correlated with self-efficacy(r=.499, p=.0000), hardiness (r=-.275, p=.0000), health promotion behavior(r=.428, p=0000). 3) Self-efficacy was positively correlated with hardiness(r=-.423, p=.0000), health promotion behavior(r=.492, p=.0000). 4) Hardiness was positively correlated with health promotion behavior(r=-.457, p=.0000). 4. Self-efficacy, hardiness and self-esteem were the major predictors for health promoting behavior(35.7%).

• 한국건축시공학회지
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• 제7권2호통권24호
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• pp.99-106
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• 2007

The purpose of this study presents in Relations between cracks in self-leveling material and quality of floor groundwork surface are experimentally examined. As the first stage, the experiment to observe cracks in self-leveling material constructed on floor groundwork made from various kinds of concrete was carried. As a result, following basic findings were obtained. First, observation of cracks should be continued until an increase in width of cracks stop, without constructing any finishing material. Second, degree of cracks may be indicated quantitatively by the product of length and width. Finally, Cracks and separation is not be influenced by specimen size. Based on these findings, the method of predicting cracks by evaluating surface layer quality of floor groundwork will be established.

• Computers and Concrete
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• 제19권1호
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• pp.33-39
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• 2017

In this study, two types of aggregate were used for making self-compacting concrete. Standard cubic specimens were exposed to different temperatures. Seventy-two standard cylindrical specimens ($150{\times}300mm$) and Seventy-two cubic specimens (150 mm) were tested. Compressive strengths of the manufactured specimens at $23^{\circ}C$ were about 33 MPa to 40 MPa. The variable parameters among the self-compacting concrete specimens were of sand stone type. The specimens were exposed to 23, 100, 200, 400, 600, and $800^{\circ}C$ and their mechanical specifications were controlled. The heated specimens were subjected to the unconfined compression test with a quasi-static loading rate. The corresponding stress-strain curves and modulus of elasticity were compared. The results showed that, at higher temperatures, Scoria aggregate showed less sensitivity than ordinary aggregate. The concrete made with Scoria aggregate exhibited less strain. The heated self-compacting concrete had similar slopes before and after the peak. In fact, increasing heat produced gradual symmetrical stress-strain diagram span.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.108-113
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• 1999

In structures, it is important to improve the capacity of waterproof in aspect of the durability and management of maintenance. Among the method of waterproof, self waterproof method is to improve the capacity of waterproof of structure itself. Thereby, we can expect the effect of durability and economics. In this study, we investigated the adding effect of waterproof admixture according to the water-cement ratio when used powder self waterproof admixture and analyzed the change of microstructure. Also, we were made to clear the mechanism of self waterproof admixture and intended to suggest the basic data on developing self waterproof admixture.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권2호
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• pp.51-54
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• 2005

In this work, the attempt has been made to investigate the morphology of self-assembled dipyridinium dithioacetate on Au(111) substrate by Scanning Tunneling Microscopy(STM). Also, we measured electrical properties(I-V) using Scanning Tunneling Spectroscopy(STS). Sample used in this experiment is dipyridinium dithioacetate, which contains thiol functional group, this structure that can be self-assembled easily to Au(111) substrate. The self-assembly procedure was used for two different concentrations, 0.5 mM/ml and 1 mM/ml. Dilute density of sample by 0.5 mM/ml, 1 mM/ml and observed dipyridinium dithioacetate's image by STM after self-assembled on Au(111) substrate. The structure of STM tip-SAMs-Au(111) substrate has been used measurement for electrical properties(I-V) using STS. The current-voltage(I-V) measurement result, observed negative differential resistance(NDR) properties.

• 가정과삶의질연구
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• 제24권2호
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• pp.61-71
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• 2006

The purpose of this study was to investigate the relationships between parental childrearing attitude and parental childrearing behavior and the effect of parental childrearing attitude and parental childrearing behavior on children's self-efficacy. The subjects included 293 children from the 4th grade to the 6th grade in two elementary schools in Seoul and Incheon. The results were as follows: First, the subjects recognized the difference between parental childrearing attitude and parental childrearing behavior; Second, the children's self-efficacy varied depending upon the style of parental childrearing attitude and the level of recognition of parental childrearing attitude by the children; Third, the children's self-efficacy varied depending upon the style of parental childrearing behavior and the level of recognition of parental childrearing behavior by the children. Several suggestions were made concerning future parental childrearing attitude and parental childrearing behavior.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 I
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• pp.482-487
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• 2001

This paper introduces a Lorentz force type four-pole self-bearing motor, where the new pole arrangement of a stator is intended to function both as a synchronous PM motor and as a magnetic bearing. The Lorentz force type has some good points such as linearity of control force, freedom from flux saturation, and high efficiency unlike conventional self-bearing motors. Mathematical expressions of torque and radial force are derived to show that they can be separately controlled regardless of rotational speed and time. To verify the proposed theory, a prototype is made, where a ring-shape outer is actively controlled in two radial directions while the other motions are passively stable supposing the radial stability. Through some experiments, it is shown that the proposed scheme can provide high capability and feasibility for a small high-speed self-bearing motor.

• 가정과삶의질연구
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• 제10권1호통권19호
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• pp.157-170
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• 1992

The main purpose of this article was to examine the general tendency of self-disclosure and perceived self-disclosure in married couples, and to study the effect of demographic variables on them. and to find out how dyadic trust affects on self-disclosure in married couples. Considering those purposes, the following research questions have been raised : 1) What is the general tendency of self-disclosure in married couples? 2) What is the general tendency of perceived self-disclosure in married couples? 3) Does perceived self-disclosure affect on self-disclosure in married couples? 4) How do the demographic varibles affect on self-disclosure in married couples? 5) Does dyadic trust affect on self-disclosure in married couples? To solve these questions, a questionnaires which consisted of 8 items for demographic variables, of which 8 questions are for dyadic trust, and 36 questions for self-disclosure in married couples was made. This reserch 몽 been conducted from April 4, 1990 to April 15, 1990. which surveyed 560 married men and women who are living in Seoul. Only answers from 432 married men and women were analysed out of them. The analytic methods adopted in this study were the frequency, the perentage, t-test, oneway ANOVA, DUNCAN -tst, and pearson's r. Especially SPSS/${pc}^+$ program was used in order to promate the feasibility in statistical analysis. The major findings of the study are as follows : 1) Self-disclosure in married couples in generally higher than expected(M=40.4) : wife's self-disclosure(M41.5) is higher than husband's self-disclosure(M=39.4) 2) Between self-disclosure and perceived self-disclosure in married couples correlated considerably high(husband r=0.67, wife r=.75) 3) Self-disclosure in married couples are affected by the variables such as age, length of marriage, everage family income a month. 4) Self-disclosure in married couples correlated relatively low with dyadic trust(husband r=0.21, wife r=.31)

• 대한간호학회지
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• 제24권2호
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• pp.278-302
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• 1994

This article reviewed and analyzed 39 studies on self efficacy theory applied to health related behavior. The following analysis was done : 1) study subjects 2) measurement tools 3) analysis according to the type of research design(intervention re-search, explanatory research). Some findings are summarized as follows : The study subjects were both healthy people in various developmental stages and patients with various illnesses. The health related behaviors examined in the studies were also various including exercise, smoking cessation, self care behaviors, etc. The measurement of self efficacy was done with specific tools in most studies. In the tools, activities that measured the health behavior domain were listed according to increasing difficulty or contexual arrangement or in combination of both of them The analysis of 17 intervention research studies showed that generally the intervention program increased the self efficacy level of subjects and then the increased strongly self efficacy influenced behavioral changes. Most studies used more than one intervention method for increasing the self efficacy level. these were derived from sources of self efficacy suggested by Bandura. The analysis of 21 explanatory research studies showed that self efficacy strongly influenced behavior change and persistence. The major independent variable to affect the self efficacy was performance accomplishment in the past. Self efficacy explained more of the variance in health related behavior when it was applied with the variables in the health belief model, health promotion model, and reasoned action theory. On the basis of the above findings, the following suggestions are made : 1. For a desirable research design, self efficacy should be the intervening variable. That is, desirable designs would include intervention-self efficacy-behavior in intervention research studies and antecedent-self efficacy-behavior in explanatory research studies. 2. More prospective, longitudinal studies are needed to test the effect of self efficacy on persistence in health related behavior. 3. Studies comparing the effects of intervention methods are needed for each health related behavior, subject group, and context. 4. It is necessary to develop a reliable, valid measurement tool for self efficacy for each health related behavior. 5. Studies to differenciate the effect of self efficacy from that of outcome expectation on the health related behavior are necessary. 6. The antecedents of self efficacy should be investigated further.