• 한국석유지질학회:학술대회논문집
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• spring
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• pp.1-11
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• 1997

Thirty one samples from Late Cretaceous and Tertiary interval sections (468-783m) of the Kachi-I Well in Block II, Yellow Sea Basin, have been analysed for their terrestrially derived palynofloras. The systematic study of the palynomorphs recovered has yielded one hundred and fifty-five taxa; forty-three species of spores belonging to twenty-eight genera, seventy-seven pollen assignable to forty-three genera, and twenty-seven species assignable to fifteen genera and eight fungal remains. The results of both qualitative and quantitative analysis propose a succession of eight terrestrial palynomorph associations. Seven associations are erected in Late Maastrichtian and one in Early to Middle Miocene. Age determinations are on the basis of palynomorph taxa alone for the all associations. The Late Cretaceous/Tertiary unconformity is recognised at between 603 and 613m, based on the palynological data. The sedimentary basin during the Late Cretaceous seem to be lowland shallow marginal lacustrine with stagnant, mesotrophic conditions. On the other hand, the basin during the Early-Middle Miocene is considered to have been characterised by lowland swamp areas. The palaeoclimatic conditions during the Late Cretaceous are considered to be humid tropical to subtropical, while during the Early to Middle Miocene they are considered to be warm temperate with humid conditions. A comparison of palynomorph assemblages between the present study and the previous studies of Late Cretaceous in Circum-Pacific Northern Hemisphere is made, These assemblages reveal that lower sections (612-783m) of the Kachi-I well belong to the Late Cretaceous Aquilapollenites province of Herngreen and Chlonova (1981) and Srivastava (1981, 1994).

• Korean Journal of Health Education and Promotion
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• v.33 no.5
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• pp.13-21
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• 2016

Objectives: The present study aims to examine associations between job demands and problem drinking, smoking, and practice of regular exercise among middle-aged and older male employees. Methods: Analyses were based on 239 employees aged 50+ and participated the 1st(2006) and the 4th(2012) waves of the Korean Longitudinal Study of Ageing(KLoSA). Panel logit regression analyses were performed to explore longitudinal associations between physical and cognitive job demands and the health behaviors when effects of demographic characteristics and objective job conditions were controlled. Results: Results suggested that first, workers who reported greater cognitive job demands were less likely to engage in problem drinking over the 6-year-period. Second, increased physical demands of the job were associated with greater odds of smoking, while physical demands predicted a reduced likelihood of practicing regular exercise. Conclusions: Results from the present analyses emphasize job demands could lead workers to problem health behaviors and suggest areas for health promotion efforts at the workplace that are sensitive to the needs of aging workers.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6211-6217
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• 2014

Previous genome-wide association studies (GWAS) have implicated several single nucleotide polymorphisms (SNPs) in the AT-rich interactive domain 5B (ARID5B) gene with childhood acute lymphoblastic leukemia (ALL). However, replicated studies reported some inconsistent results in different populations. Using meta-analysis, we here aimed to clarify the nature of the genetic risks contributed by the two polymorphisms (rs10994982, rs7089424) for developing childhood ALL. Through searches of PubMed, EMBASE, and manually searching relevant references, a total of 14 articles with 16 independent studies were included. Odds ratios (ORs) with 95% confidence intervals (95%CI) were calculated to assess the associations. Both SNPs rs10994982 and rs7089424 showed significant associations with childhood ALL risk in all genetic models after Bonferroni correction. Furthermore, subtype analyses of B-lineage ALL provided strong evidence that SNP rs10994982 is highly associated with the risk of developing B-hyperdiploid ALL. These results indicate that SNPs rs10994982 and rs7089424 are indeed significantly associated with increased risk of childhood ALL.

• Korean Security Journal
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• no.32
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• pp.177-204
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• 2012

The purpose of this study is to search for a plan to improve the professionalization of private investigation service through the analysis of its actual condition. To examine the actual condition of the professionalization of private investigation service, 4 factors - professional associations, professional knowledge, curriculum & qualification system and code of ethics - were used for the professionalization analysis based on theoretical background and prior researches concerning structural aspect of professionalization. Based on the results of actual condition analysis, to make an effort for the integration and incorporation of private investigation associations, to overcome the unequal distribution of professional knowledges, to organize and operate the professional curriculum, to introduce recognized qualifications system, and to establish a code of ethics are required to improve the professionalization of private investigation service.

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.1
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• pp.17-26
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• 2004

In this study, the usability evaluation of a menu-structure was performed using spreading activation model with respect to human's memory retrieval. Spreading Activation Model is effectively used to understand the process of information retrieval, so it can be used as a theoretical background for modeling of the process of human's information retrieval. For spreading activation test (SAT), subjects were presented with 67 pairs of menu titles, which consist of a menu title in the high level menu item and a menu title for the next lower level menu item, from Korea University's web site. For performance tests, three scenarios were developed with longer reaction times and ambiguous associations found in the SAT to reflect the existing problems of the website. As a result, the SAT was found to bean effective tool to enhance the website usability because the SAT could bea substitute for the performance test with a high correlation $({\rho}=0.735,\;{\alpha}=0.05)$. After remaining menu titles with slow reaction times and ambiguous associations found in SAT, the website usability was significantly improved with faster reaction times and less ambiguous associations proven with smaller number of web-page visits. Therefore, the SAT could be used as a methodology to design and evaluate the user-centered menu structure related to human's association structure.

• Child Health Nursing Research
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• v.25 no.4
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• pp.487-495
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• 2019

Purpose: We aimed to identify associations between the frequency of electronic cigarette (e-cigarette) use and smoking-related characteristics among adolescent smokers. Methods: We used data from the 14th Korea Youth Risk Behavior Survey. The participants were 3,722 smokers who had smoked cigarettes on at least one day during the past 30 days. The frequency of e-cigarette use was defined as the number of days that participants used e-cigarettes during the past 30 days, and was divided into four categories: 0, 1~2, 3~9, and ${\geq}10$ days. We used the $x^2$ test and multinomial logistic regression to examine the associations between the frequency of e-cigarette use and smoking-related characteristics. Results: Those who attempted to quit smoking, had used a heated tobacco product (HTP) at least once, or initiated e-cigarette use before middle school were more likely to use e-cigarettes for 3~9 days in the past 30 days. More frequent e-cigarette use (${\geq}10$ days) was associated with a higher frequency and greater amount of cigarette use, lifetime HTP use, and earlier initiation of e-cigarette use. Conclusion: Smoking-related characteristics differed by the frequency of e-cigarette use. Therefore, intervention programs targeting adolescent smokers should consider differences in smoking-related characteristics based on the frequency of e-cigarette use.

• Journal of Power Electronics
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• v.19 no.1
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• pp.68-78
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• 2019

The emergence of high voltage conversion applications has resulted in a trend of using semiconductor device series associations. Series associations allow for operation at blocking voltages, which are higher than the nominal voltage for each of the semiconductor devices. The main challenge with these topologies is finding a way to guarantee the voltage balance between devices in both blocking and switching transients. Most of the methods that have been proposed to mitigate static and dynamic voltage unbalances result in increased losses within the device. This paper introduces a new series stack topology, where the voltage unbalances are reduced. This in turn, mitigates the switching losses. The proposed topology consists of a circuit that ensures the soft switching of each device, and one auxiliary circuit that allows for switching energy recovery. The principle for the topology operation is presented and experimental tests are performed for two modules. The topology performs excellently for switching transients on each of the devices. The voltage static unbalances were limited to 10%, while the activation/deactivation delay introduced by the lower module IGBT driver takes place in the dynamic unbalances. Thus, the switching losses are reduced by 40%, when compared to hard switching configurations.

• Educational Technology International
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• v.22 no.2
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• pp.285-309
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• 2021

It is commonly understood that students' autonomous motivation and individualistic orientations and instructors' autonomy support are important for student-centered learning (SCL). However, few studies have examined this assumption. To help researchers and practitioners design more engaging SCL experiences across diverse cultural contexts, this study examines the associations of these factors with SCL engagement and how these associations compare in different cultures. University students in South Korea and the United States participated in a bold SCL assignment, called Pink Time, in which students decide what and how they learn. Linear, multivariate models were estimated in each context to identify and compare relationships between SCL engagement and student characteristics and perceptions. We found that engagement was high in both contexts. Autonomous motivation, individualism, and perceived instructor support each had significant associations with SCL engagement in South Korea. In the US, which had a smaller sample size, only perceived instructor support was significantly associated. These findings suggest that SCL strategies can be effective across cultures. Also, the narrower classroom context, specifically instructors' support, may be a stronger driver of engagement than the broader societal context. This study contributes to the scholarly discussion regarding SCL in diverse settings and offers several implications for instructors.

• Genomics & Informatics
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• v.20 no.2
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• pp.17.1-17.11
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• 2022

Genetic associations have been quantified using a number of statistical measures. Entropy-based mutual information may be one of the more direct ways of estimating the association, in the sense that it does not depend on the parametrization. For this purpose, both the entropy and conditional entropy of the phenotype distribution should be obtained. Quantitative traits, however, do not usually allow an exact evaluation of entropy. The estimation of entropy needs a probability density function, which can be approximated by kernel density estimation. We have investigated the proper sequence of procedures for combining the kernel density estimation and entropy estimation with a probability density function in order to calculate mutual information. Genotypes and their interactions were constructed to set the conditions for conditional entropy. Extensive simulation data created using three types of generating functions were analyzed using two different kernels as well as two types of multifactor dimensionality reduction and another probability density approximation method called m-spacing. The statistical power in terms of correct detection rates was compared. Using kernels was found to be most useful when the trait distributions were more complex than simple normal or gamma distributions. A full-scale genomic dataset was explored to identify associations using the 2-h oral glucose tolerance test results and γ-glutamyl transpeptidase levels as phenotypes. Clearly distinguishable single-nucleotide polymorphisms (SNPs) and interacting SNP pairs associated with these phenotypes were found and listed with empirical p-values.

• Journal of Distribution Science
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• v.22 no.2
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• pp.115-123
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• 2024

Purpose: Using the association concept as a basis, businesses offer association cues-trademarks and logos, for example-to support consumers' associative memories. These stimuli can be connected to anything, including a product's unique personality or the advantages it offers the company that made it. The purpose of this study is to comprehend how hypermarkets' business affiliation, relationship commitment, and trust affect consumers' attitudes and behaviors. Data, methodology, and research design: Regression analysis was used in this study to confirm the relationship between the independent and dependent variables, as well as to forecast how the changes in the independent variable would affect the changes in the dependent variable. Results: These are the findings of the research. First, it was discovered that trust and relationship commitment were significantly impacted by the hypermarket product association, corporate management-related associations, and social responsibility associations. Second, it was discovered that both behavioral and attitudinal loyalty were impacted by hypermarkets' level of trust. Third, it was discovered that both behavioral and attitudinal loyalty were impacted by a hypermarket's relationship commitment. Conclusions: Corporate associations with the hypermarket play an important role in shaping and maintaining consumers' awareness of the company or brand. Since this is affected by various factors such quality of products and services, and corporate social activities, companies need to positively induce awareness of products or services.