• Journal of Educational Research in Mathematics
• /
• v.27 no.3
• /
• pp.375-389
• /
• 2017

The purpose of this study is to analyze the difference and inter-connectivity between the definition of continuity in school mathematics and the definition of academic mathematics in four perspectives. These difference and inter-connectivity have not analyzed in previous papers. According to this study, the definition of 'continuity and discontinuity at one point' in school mathematics depends on the limit processing but in academic mathematics it depends on the topology of the domain. The target function of the continuous function in school mathematics is a function whose domain is limited to an interval or a union of intervals, but the target function of the continuous function in academic mathematics is all functions. Based on these results, the following two opinions are given in relation to the concept of continuity in school mathematics. First, since the notion of local continuity in school mathematics is based on limit processing, the contents of 2009-revised textbooks that deal with discontinuity at special point not belonging to the domain is appropriate. Here the discontinuity appears as types of infinite discontinuity, removable discontinuity, and step discontinuity. Second, the definition of a general continuous function is proposed to "if there is no discontinuity point in the domain of a function y = f(x), we call the function f a continuous function." This definition allows the discontinuity at special point in non-domain, but is consistent with the definition in academic mathematics.

• Journal of Preventive Medicine and Public Health
• /
• v.33 no.3
• /
• pp.343-348
• /
• 2000

Objectives : This study was conducted to integrate the results of studies assessing the association between chronic noise exposure and blood pressure. Methods : Using a MEDLINE search with noise exposure, blood pressure and hypertension as key words, we retrieved articles from the literature that were published from 1980 to December 1999. The criteria for quality evaluation were as follows: 1) the study subjects must have been workers employed at a high noise level area 2) The paper should use average and cumulative noise exposure as method for exposure evaluation. 3) Blood pressure in each article should be reported in a continuous scale Among the 77 retrieved articles, six studies were selected for quantitative meta-analysis. Before the integration of the regression coefficients for the association between blood pressure and noise level, homogeneity tests were conducted. Results : All studies were a cross-sectional design and the study subjects were industrial workers. Five papers used a time-weighted average for noise exposure and only one paper calculated the cumulative noise exposure level. The measurement of blood pressure in the majority of studios were accomplished in a resting stale, and used an average of two or more readings. The homogeneity of studies was rejected in a fixed effect model, so we used the results in a random effect model. The results of the quantitative meta-analysis, the weighted regression coefficient of noise associated with systolic blood pressure and diastolic blood pressure were 0.05 (95% confidence interval [CI]: -0.03, 0.13) and 0.06 (95% CI: -0.01, 0.13), respectively. Conclusions : Our results suggested that chronic exposure to industrial noise does not cause elevated blood pressure.

• Journal of Technology Innovation
• /
• v.19 no.1
• /
• pp.145-175
• /
• 2011

The purpose of this research investigates the determinant factors of the joint technology development project performance between SMEs and universities. Reviewing existing papers we could categorize independent variables into three groups of partner characteristics, process management variables and relationship characteristics between partners. Three measures of satisfaction with the cooperation result, the intention of continuing relationship and the utilization of developed technology and product were used as dependent variable considering that we studied the joint projects of SMEs' involvement, short period and small scale. The data was collected by questionnaire survey mailed to the 1082 SMEs and university professors which executed the joint projects sponsored by Small Business Administration in 2009. We received 200 responses from SMEs, and 305 cases from professors among which 55 responses of each partner were on the same project. We analyzed the data sets individually, data of SMEs and that of universities with multiple regression analysis technique and also analyzed the common responses of 55 projects. Analysis results of the data from SMEs indicated that partners' expertise, facilities and equipment, communications, strategic importance, and trust were significant variables for the project performance. Analysis results of the data from universities showed that previous links, definition of objectives, strategic importance, trust and commitment were significant variables. Analysis results of combined data of 55 projects from SMEs and universities indicated that facilities and equipment, project management proficiency and commitment were significant variables.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.3
• /
• pp.186-197
• /
• 2018

This study was a systematic review and meta-analysis designed to investigate the effects of physical activity programs on sleep among community-dwelling elders in Korea. Based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines, research articles published until November 20, 2016 were systematically analyzed and a total of seven papers were finally selected. Meta-analysis of the studies was conducted using Comprehensive Meta-Analysis 3.0. The results showed that the total effect of the physical activity program for elderly people, such as healing yoga, aerobic dance, aquarobics, Korean dance, BeHas exercise, exercise programs and Tai Chi exercise on sleep was Hedges' g=0.577 (95% CI: 0.337-0.817) The BeHas exercise program had the largest effect size on elderly's sleep, with a Hedges' g=0.758 (95% CI: 0.248-1.267). This was followed by the Tai Chi exercise program (Hedges' g=0.697; 95% CI: 0.071-1.324) and the exercise program (Hedges' g=0.650; 95% CI: 0.141-1.159). Therefore, when applying nursing interventions to improve quality of sleep of elderly people living in the community, it would be helpful to apply the BeHas exercise and the Tai Chi exercise, which have a positive effect on sleep of the elderly.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.18 no.1_2
• /
• pp.27-32
• /
• 2012

There are many possibilities that recycled papers adulterate contaminants during the process. The objective of this research was to evaluate safety of paper-based packaging materials for food, especially commercial pizza boxes in Korea. Ultimately, we compared recycled and non-recycled commercial paper packaging materials. This study was based on Korean Food and Drug Administration (KFDA) regulation. PCBs were measured by GC-ECD. Arsenic and lead were analyzed using an ICP-MS. Formaldehyde was determined by LC-MS. Fluorescent materials were detected by UV lamp. The result of this study shows that non-recycled paper packaging materials meets all the tested hygienic specifications for food packaging materials, whereas recycled paper-based paperboard box may be contaminated by fluorescent whitening agent. Though these results need to be further studied, it is recommended to avoid using recycled paper in direct contact with food when used in food packaging.

• Journal of the Korean Society of Costume
• /
• v.59 no.3
• /
• pp.157-165
• /
• 2009

This study intends to discuss the efficient stage costume design that uses costume-rentals and production method as a realistic alternative for production of stage costume of low budget performance. Directly participating in the costume design and production of the performance , this researcher applied the methodology of corroborative study on the basis of production process and results by referring to the papers and literature published by academic society for the theory necessary for study. Centering around the western costume in the stage costumes of , the scope of study was the costume of Paris, France prevalent at the end of the 19th century which is epochal background of performance. In spite of its merit of reducing production charge and production in the low budget performance, costume-rentals is subject to the lack of considering unitγ with other visual factors and limit in reflecting the creativity of costume designer. The following actions shall be taken to solve such problem. First, it is essential to set production direction and plan that meets budget and work concept. Second, it is required to highlight the characteristic factor of the age which is the background of work so as to grant the sense of age and to produce the visual unity of costume by supplementing the costume composition. Third, it is necessary to make large effect with low lost by using costume articles that can express the characteristics of the age. Fourth, it is required to efficiently reflect the transformation of design by minimizing the damage of costume through research on the sewing method and materials as well as creative idea. In this way, the efficient stage costume could be realized in the performance with low budget by approaching costume-rentals in the viewpoint of costume design, transforming it in accordance with work concept and adding the visual factors.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.14 no.3
• /
• pp.509-521
• /
• 1994

This study is an effort to develop computer simulation model that produce precipitation patterns from stochastic model. A stochastic model is formulated for the process of daily precipitation with considering the sequences of wet and dry days and the precipitation amounts on wet days. This study consists of 2 papers and the process of precipitation occurrence is modelled by an alternate renewal process (ARP) in paper (I). In the ARP model for the precipitation occurrence, four discrete distributions, used to fit the wet and dry spells, were as follows; truncated binomial distribution (TBD), truncated Poisson distribution (TPD), truncated negative binomial distribution (TNBD), logarithmic series distribution (LSD). In companion paper (II) the process of occurrence is developed by Markov chain. The amounts of precipitation, given that precipitation has occurred, are described by a Gamma. Pearson Type-III, Extremal Type-III, and 3 parameter Weibull distribution. Daily precipitation series model consists of two models, A-Wand A-G model, by combining the process of precipitation occurrence and a continuous probability distribution on the precipitation of wet days. To evaluate the performance of the simulation model, output from the model was compared with historical data of 7 stations in the Nakdong and Seomjin river basin. The results of paper (1) show that it is possible to design a model for the synthetic generation of IX)int precipitation patterns.

• Journal of Science Education
• /
• v.38 no.1
• /
• pp.168-181
• /
• 2014

The purpose of this study was to monitor evaluation in science education at primary and secondary school in Korea. In order to do this, the survey was administered. The subject was 518 teachers; 292 elementary school teachers, 110 middle school science teachers and 116 general high school science teachers. It was found that the ratio of paper examination increased while that of performance evaluation decreased according to the grade of school. In the science paper examination, the ratio of selection type item was higher than that of supply type item, and the ratio of item belonging to knowledge area was higher than that of item belonging to the inquiry area regardless of the grade of school, teaching career, and teacher's gender. The teachers recognized the necessity of supply type item, but they suffered from the reliability of the result of that item. And it was hard for them to do performance evaluation because it took much time and effort. This study suggested that the high-quality in-service teacher training be provided and laboratory assistants who help the science experiment and grading test papers be employed in order to fulfil the performance evaluation and increase the ratio of supply type item and items belonging to the inquiry area.

• Archives of design research
• /
• v.18 no.1 s.59
• /
• pp.5-16
• /
• 2005

As for the public, it is hard to understand semiotics because of the scope of an enormous semiotics education. This study is making semiotics of Charles Sanders Peirce the subject. I thought that utilization can hold his semiotics study in a visual design field. First of all, this study considered design related papers related to the existing semiotics again and study found an error of the existing semiotics study and understanding did category concept with re-definition about semiotics of Peirce. Explained a symbol mark through understanding of semiotics of Peirce. This study was able to get the following conclusion through these results. 1) A symbol mark means one product, sonics, company oneself with a custom. Therefore, it is a rule symbol in the Representation side. 2) A symbol mark symbolizes an object with one symbol, so a symbol mark is a symbol in an object. 3) Because a symbol mark exists through a social rule, in semiotics definition of Peirce, this must become understanding with a Argument symbol. 4) A symbol mark is what a company or an organization field used from the past, and the public are recognizing this how. Therefore, it works as fact a company attaches a symbol mark to own product, and to show the public a symbol mark. A symbol mark is Dicent Sign in Interpretant. A rule and understanding about a lot of types which have various mutual relation, Peirce classification and understanding of a symbol mark tells to demand is holding that understanding a type of semiotics with the concept that is not an image to us.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.7
• /
• pp.207-213
• /
• 2018

To increase the acceptance of multicultural youth, it is necessary to grasp the factors influencing multicultural acceptance. This study was conducted to provide basic data for a future study for the promotion of multicultural acceptance of adolescents by systematically analyzing research trends in factors affecting the multicultural acceptance of Korean adolescents. From 2008 to 2017, we searched 6,435 papers combining the keywords 'multicultural,' 'acceptability,' 'teenager,' 'middle school' and 'high school,' and analyzed six articles. The qualitative evaluation refers to Community Guide and STrengthening the Reporting of OBservational studies in Epidemiology(STROBE). The results revealed that factors influencing multicultural acceptance include gender, experience of overseas visits, life satisfaction, parental neglect and abuse, parent education, school and community factors, and community awareness. Multicultural acceptance of adolescents in Korea was influenced not only by specific factors, but also by various factors such as individual, family, school, and community. These factors were also found to change with age. Based on the results of this study, it is necessary to provide an environment and education that promote multicultural acceptance.