• School Mathematics
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• v.16 no.1
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• pp.19-37
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• 2014

This study investigated the degree of understanding pre-service teachers' random variable concept, based on the attention and the importance for developing pre-service teachers' ability on statistical reasoning in statistics education. To accomplish this, the subject of this study was 70 pre-service teachers belonged to three universities respectively. The teachers were given to 7 tasks on random variable and requested to solve them in 40 minutes. The tasks consisted of three contents in large; 1) one was on the definition of random variables, 2) the other was on the understanding of random variables in different/diverse conditions, and 3) another was on problem solving relevant to random variable concept. The findings are as follows. First, while 20% of pre-service teachers understood the definition of random variable correctly, most teachers could not distinguish between random variable and variable or probability. Second, there was a significant difference in understanding random variables in different/diverse conditions. Namely, the degree of understanding on the continuous random variable was superior to that of discrete random variable and also the degree of understanding on the equal distribution was superior to that of unequality distribution. Third, three types of problems relevant to random variable concept dealt with in this study were finding a sample space and an elementary event, and finding a probability value. In result, the teachers responded to the problem on finding a probability value most correctly and on the contrary to this, they had the mot difficulty in solving the problem on finding a sample space.

• Journal of Families and Better Life
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• v.23 no.3 s.75
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• pp.1-16
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• 2005

This study explored the elements, types, and determining factors of successful aging for the Korean elderly. In order to examine the expectations of the Korean elderly, a sample of 377 elderly aged 65 and over living in Seoul and Kyunggi areas was selected and interviewed. The elements of successful aging that the Korean elderly pointed out in the interviews were: 'peaceful and comfortable life', 'self-maintenance,' 'secure social support,' and 'ostentation.' The expected elements of successful aging were further classified into three types of successful aging: 'idealized expectation.' 'self-centered expectation,' 'balanced self-other expectation.' The elderly groups sorted by the types exhibited significant differences in terms of demographic characteristics, self-evaluated economic status, and self-evaluated health status. The variables that affected the expectations were age, level of education, marital status, gender, and self-evaluated health condition. However, further analysis revealed that the factors that affected the expectation for successful aging were different for male and female elderly. The results suggest that the successful aging of Korean elderly should be understood in the context of Korean society and culture. The results could be used to better understand varied and unique life of Korean elderly, as well as in establishing a basis of intervention that meets the specific demands of the Korean elderly.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.8
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• pp.3888-3910
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• 2018

As an increasing number of defense methods against control-data attacks are deployed in practice, control-data attacks have become challenging, and non-control-data attacks are on the rise. However, defense methods against non-control-data attacks are still deficient even though these attacks can produce damage as significant as that of control-data attacks. We present a method to defend against non-control-data attacks using influence domain monitoring (IDM). A definition of the data influence domain is first proposed to describe the characteristics of a variable during its life cycle. IDM extracts security-critical non-control data from the target program and then instruments the target for monitoring these variables' influence domains to ensure that corrupted variables will not be used as the attackers intend. Therefore, attackers may be able to modify the value of one security-critical variable by exploiting certain memory corruption vulnerabilities, but they will be prevented from using the variable for nefarious purposes. We evaluate a prototype implementation of IDM and use the experimental results to show that this method can defend against most known non-control-data attacks while imposing a moderate amount of performance overhead.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.1
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• pp.144-151
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• 2003

In this paper, an optimum design problem for endosseous implant in dentistry is studied to find best implant design. An optimum design problem is formulated to reduce stresses arising at the cortical as well as cancellous bones, in which sufficient design parameters are chosen fur design definition that encompasses major implants in popular use. Optimization at once (OAO) with the large number of design variables, however, causes too costly solution or even failure to converge. A concept of multilevel optimization (MLO) is employed to this end, which is to group the design variables of similar nature, solve the sub-problem of smaller size fur each group in sequence, and this is iterated until convergence. Each sub-problem is solved based on the response surface method (RSM) due to its efficiency for small sized problem. Favorable solution is obtained by the MLO, which is compared to both solutions made by RSM and sequential quadratic programming (SQP) in the OAO problem.

• Journal of Distribution Science
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• v.14 no.12
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• pp.23-30
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• 2016

Purpose - As socially responsible consumption increases, green marketing emerges as a new philosophy in marketing. A number of companies are now putting forth green marketing strategies. But there is no single definition of "green brand" that can be used interchangeably. In this paper, we attempt to explore the meaning for "green brand," especially in Information and Technology products. Research design, data, and methodology - The author developed qualitative and quantitative research design. In particular, the paper approaches this topic from the Asian consumers' perspective and applies ethical concepts to green brand research. For this, Chinese and Korean consumers were used as consumer segmentation variables to investigate their ethical perspectives. Results - Qualitative research showed that there are several attributes and benefits we need to consider for green brand. Quantitative study showed positive correlations of the two variables: the higher the consumer ethics are, the more they prefer green brands. Conclusions - The current study shows that consumers clearly have a certain propensity toward green brand equity. Thus, marketers should consider the consumers' evaluation about green brands. This paper also proposes that ethics have a close relationship with green brand equity, and companies may use ethics in marketing strategy management.

• Journal of Families and Better Life
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• v.7 no.1
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• pp.97-118
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• 1989

The purpose of this study is to clarify the definition of middle age, to compare the different perspectives about mid-life crisis, and to identify the variables that cause the mid-life crisis of men and women.. For this purpose reviewing literatures and emprical research were conducted. For the emprical research, Mid-life Crisis Scale, Mid-life Indentity Scale, Family Relation Scale. Health Scale and Religious Scale were developed. The Sample was selected form the men and women living in Seoul, whose age is from 40 to 59 , and whose last child is older than 13 years of age. Among 820 respondents 218 men and 442 women were finally selected as datum sources. The data were analyzed by the statistical method such as the factor analysis frequency distribution, percentile, ANOVA, Pearson's correlation and regression analysis. The main results were as follows; 1) Men and women experience mid-life crisis some extent. The mid-life crisis score for men is 33.60 and 35.0 for women. This implies women reveal significantly higher crisis than men. As for women's mid-life crisis. self-awaring age, education, income, husband's occupation, employment status of wife and occupational status of wife have a significant influence Expecially employment status of wife seemed to interact with sex, husband's occupation and educational level of wife. however status of child, family pattern, son's existence are not as important an influence on mid-life crisis. 3) Among the psychological variables, work identity and physical identity have the strong influence on the mid-life crisis of men and women, It implies that mid-life crisis si lower when one has higher work identity and physical identity. 4) Mid -life crisis of men and women is influenced significantly according to family relation variables and health variables. It reveals that the better one's family relations and health sate, the lower one's mid-life crisis is. However menopause and the years after menopause do not influence on the mid-life crisis of women. 5) Mid-life crisis of women differs significantly according to the kind of religion and religious activity. That is mid-life crisis of women is lower when she believes in Protestantism and Catholicism and participate in more religious activity. Mid-life crisis of men is not significantly influenced by religious variables. After all among the five categories of variables that related to mid-life crisis, psychological variables-especially work identity and physical identity are observed to have the strongest degree of significance.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.1
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• pp.11-18
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• 1999

The objective of this study are to figure out the physical attributes of the three predictors in the Informational Approach: complexity, coherence, mystery and to investigate the relationships between these attributes and the preference exploratively. Visual inspection of the scenes relative to their rated levels of the predictors revealed the existence of relationship between these variables and the physical attributes. The following are the summary of the relationship between three predictors and the physical attributes: (1) The level of complexity was associated with the pattern of physical attributes which were the amount of facility, line, shape, color plant and arrangement of the visual elements. (2) The level of coherence was related with the regular arrangement of the visual elements. For example, there was certain pattern founded the color, shape, texture was applied to the various space repetitively and symmetrically. (3) The level of mystery had the relationship with the physical attributes of screen, spatial definition, distance of view, physical accessibility, radiant forest, the depth of space.

• Journal of Information Technology Applications and Management
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• v.21 no.4_spc
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• pp.345-359
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• 2014

Technological, policy and economic factors are both important variables in maximizing the results of a national R&D program and key indicators in evaluating an R&D program's eligibility for financial support. Economic analysis, in particular, is used when selecting R&D programs, setting priorities, and estimating economic effects. This paper examines a series of methodological issues related to the economic analysis of national R&D programs within the framework of the current preliminary feasibility evaluation system, and proposes alternative approaches to each of the issues discussed. The issues include the definition of R&D valuation and establishment of valuation factors; estimation of sales attributable to R&D investment; assessment of the total economic value of R&D as intellectual assets; estimation of R&D benefits and assumption of related to sales; and the application of discount rates based on the weighted average cost of capital. Finally, this study presents directions for future research on analytical procedures and methods of improving the reliability of the results of economic analysis within the national technology planning system.

• Computers and Concrete
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• v.6 no.6
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• pp.491-503
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• 2009

This paper presents a design framework developed using axiomatic design (AD) theory that can be applied in the design process of porous concrete. The main contribution of this paper is the definition of an AD framework based on the needs and functional requirements of porous concrete. The framework shows how AD theory can be used to provide guidelines for proportioning and manufacturing porous concrete. The advantage of the AD approach is that it systemizes the way to decouple design parameters and makes designers to think rationally between what we want to achieve and how we propose to satisfy the functional requirements of porous concrete. In this paper, test results of laboratory-size porous concrete specimens under compression were analyzed to evaluate the performance of the porous concrete based on the desired functional requirements.

• Earthquakes and Structures
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• v.13 no.5
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• pp.465-471
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• 2017

This work derives a generalized time fractional differential equation governing wave propagation in a radially vibrating non-classical cylindrical medium. The cylinder is made of a transversely isotropic hyperelastic John's material which obeys frequency-dependent power law attenuation. Employing the definition of the conformable fractional derivative, the solution of the obtained generalized time fractional wave equation is expressed in terms of product of Bessel functions in spatial and temporal variables; and the resulting wave is characterized by the presence of peakons, the appearance of which fade in density as the order of fractional derivative approaches 2. It is obtained that the transversely isotropic structure of the material of the cylinder increases the wave speed and introduces an additional term in the wave equation. Further, it is observed that the law relating the non-zero components of the Cauchy stress tensor in the cylinder under consideration generalizes the hypothesis of plane strain in classical elasticity theory. This study reinforces the view that fractional derivative is suitable for modeling anomalous wave propagation in media.