• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.74-82
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• 2002

In Intensity Modulated Radiotherapy (IMRT), radiation is delivered in a multiple of Multileaf Collimator (MLC) subfields. A subfield with a small leaf-to-leaf opening is highly sensitive to a leaf-positional error. We introduce a method of identifying and rejecting IMRT plans that are highly sensitive to a systematic MLC gap error (sensitivity to possible random leaf-positional errors is not addressed here). There are two sources of a systematic MLC gap error: Centerline Mechanical Offset (CMO) and, in the case of a rounded end MLC, Radiation Field Offset (RFO). In IMRT planning system, using an incorrect value of RFO introduces a systematic error ΔRFO that results in all leaf-to-leaf gaps that are either too large or too small by (2ㆍΔRFO), whereas assuming that CMO is zero introduces systematic error ΔCMO that results in all gaps that are too large by ΔCMO = CMO. We introduce a concept of the Average Leaf Pair Opening (ALPO) that can be calculated from a dynamic MLC delivery file. We derive an analytic formula for a fractional average fluence error resulting from a systematic gap error of Δ$\chi$ and show that it is inversely proportional to ALPO; explicitly it is equal to, (equation omitted) in which $\varepsilon$ is generally of the order of 1 mm and Δx=2ㆍΔRFO+CMO. This analytic relationship is verified with independent numerical calculations.

• The korean journal of orthodontics
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• v.48 no.6
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• pp.395-404
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• 2018

Objective: To date, only a few studies have investigated the relationships between genetic polymorphisms and external apical root resorption (EARR). Hence, the aim of this systematic review was to explore the relationship between different gene polymorphisms and their association with EARR. Methods: A complete literature search was conducted by two independent reviewers. The PubMed, Science Direct, and Scopus databases were searched. In addition, the bibliographies of all textbooks and relevant articles were searched manually. A meta-analysis was performed using data entered into the electronic databases until February 28, 2017. Results: On the basis of the search, we identified 17 and 7 publications for the systematic review and meta-analysis, respectively. Odds ratio (OR) was used to evaluate the association of the interleukin 1B (+3954) polymorphism and the risk of EARR. The overall OR from the studies was used to estimate the risk of EARR. However, no association was found and no publication bias was apparent for the risk of EARR in patients receiving orthodontic treatment. Conclusions: More research on the relationship between gene polymorphism and EARR is necessary to determine better specificity of possible interactions.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.24 no.2
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• pp.95-105
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• 2017

Purpose: A systematic literature review and meta-analysis were conducted to synthesis research findings on relationships of quality of life with multi-dimensional correlates in Korean breast cancer patients. Methods: For the study purpose, 18 studies were selected through a systematic process of searching the literature. Results: Among the general characteristics, variables having a significant relationship with quality of life were age (ES=.19), marital status (ES=.15), education (ES=.19), economic status (ES=.16), job status (ES=.10), and religion (ES=.13). Among the disease characteristics, type of treatment (ES=.12), length of time since diagnosis (ES=.13), stage of disease (ES=.14), length of time since operation (ES=.10), frequency of treatment (ES=.19), wound site and pain (ES=.16) were shown to have a significant relationship with quality of life. Depression (ES=-.60), one of the psychological factor, was the variable most significantly related to quality of life. Conclusion: The findings indicate that the variables which strongly impact quality of life in breast cancer patients are depression and pain.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.48 no.5
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• pp.259-266
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• 2022

The relationship between obstructive sleep apnea (OSA) and diverse types of pain conditions have been proposed. However, no consensus on the relationship between OSA and painful temporomandibular disorders (TMDs) has been established. Therefore, this systematic review has been conducted to review the existing literatures and provide comprehensive synthesis of such literatures about OSA and painful TMDs using the evidence-based methodology. A literature search was conducted using two electronic databases, Scopus, and PubMed. Risk of bias was assessed using the risk-of-bias assessment tool for non-randomized study version 2.0. A total of 158 articles were screened from the initial search and eventually, 5 articles were included in this systematic review. One study adopted both the longitudinal prospective cohort and case-control designs and other 4 articles adopted the cross-sectional design. Two studies employed polysomnography (PSG) for the diagnosis of OSA and mentioned the results from the PSG. All cross-sectional studies demonstrated higher OSA prevalence among patients with TMD, and one cohort study suggested OSA as a risk factor for TMD. OSA appears to have potential influences on the development of TMD; however, the role of TMD in the development of OSA remains to be unknown owing to the lack of high-quality evidences.

• Communications for Statistical Applications and Methods
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• v.22 no.3
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• pp.209-222
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• 2015

Time series are used in many studies for model building and analysis. We must be very careful to understand the kind of time series data used in the analysis. In this review article, we will begin with some issues related to the use of aggregate and systematic sampling time series. Since several time series are often used in a study of the relationship of variables, we will also consider vector time series modeling and analysis. Although the basic procedures of model building between univariate time series and vector time series are the same, there are some important phenomena which are unique to vector time series. Therefore, we will also discuss some issues related to vector time models. Understanding these issues is important when we use time series data in modeling and analysis, regardless of whether it is a univariate or multivariate time series.

• Journal of Information Technology Services
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• v.3 no.1
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• pp.117-126
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• 2004

In this study an evaluation method is proposed, with the strong relationship between the ante and post audit works evaluation. The ante evaluation does in general and systematic ways, with past audit results and proposals. The criteria-based evaluation is used for the audit activities and outputs. The critical success factors for the projects applies to the activities evaluation and product evaluation framework to the output. The ante and post evaluation have the cross evaluation items to be the whole and continuous one. Eighteen common evaluation items are derived, with their own evaluation elements in detail, which have only differences of the actually done and expectations between the ante and post. The proposed evaluation makes the ante and post one to be related with each other in a systematic and objective ways, to enhance the reliability of audit results and effectiveness of the audit.

• Animal cells and systems
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• v.1 no.1
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• pp.43-52
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• 1997

Systematic relationship of 13 species representing seven orders of anthozoans, and one hydrozoan as an outgroup, were investigated. Distance and parsimony methods were used to analyze nucleotide sequence data obtained from the 18S rDNA. The inferred phylogeny indicates that two orders, Ceriantharia and Antipatharia within subclass Ceriantipatharia, are not closely related to each other. Instead, the former appears to be the most ancestral group among anthozoans but the latter is more closely related to order Actiniaria within subclass Zoantharia. The result also indicates that the actiniarian may not be a monophyletic group, because Epiactis Japonica is related more to order Scleractinia. Subclass Octocorallia appears to be a monophyletic group, within which order Pennatulacea diversed at first, and then orders Alcyonacea and Gorgonacea diversed later.

• Research in Mathematical Education
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• v.11 no.1
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• pp.1-31
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• 2007

Recent research has documented that there is a close relationship between problem posing and problem solving in arithmetic. However, most studies investigated the relationship between problem posing and problem solving only by means of standard problem situations. In order to overcome that shortcoming, a pilot study with Chinese fourth-graders was done to investigate this relationship using a non-standard, realistic problem situation. The results revealed a significant positive relationship between students' problem posing and solving abilities. Based on that pilot study, a more extensive and systematic ascertaining study was carried out to confirm the observed relationship between problem posing and problem solving among Chinese elementary school children. Results confirmed that there was indeed a close relationship between both skills.

• Journal of the Korea Convergence Society
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• v.9 no.7
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• pp.141-147
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• 2018

To investigate the relationship between dental hygiene students' stress and college life satisfaction, 299 dental students and students in Gyeongnam area studied stress, stress response scale, and university life satisfaction. The results of systematic analysis according to the scale of stress response showed high values in fatigue, frustration, depression and anger. In addition, satisfaction with stress experienced negatively. Stress can give you a negative impact that can lead to serious illness. A systematic analysis using the stress response scale is expected to help reduce stress and improve college life satisfaction when the stress of college life is expected to increase maladjustment and dissatisfaction. We suggest the development and analysis of a stress response tool suitable for dental hygienists.

• The Korean Journal of Health Service Management
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• v.7 no.3
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• pp.45-55
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• 2013

Cosmetic products are high value-added ones, and characterized by short life-cycles and income elasticity. Since most cosmetic products are procured through consults with salespersons, it is necessary to have detailed knowledge about basic cosmetics. In this paper, a possible relationship marketing strategy is suggested using the results of examining the effects of relationship marketing factors and relationship quality in cosmetics industry. The findings of this research can be summarized as follows. In order to examine the effects of relationship marketing factors and relationship quality on satisfaction which is a relationship performance, and the willingness to procure it again, this paper executed multiple regression analysis. The typical findings of this paper are as follows. The higher the specialty is, the better the brand image is, the higher customization and trust with customer are, the higher satisfaction and willingness to buy it again get. The analysis of relative influences of sub-factors revealed that trust was the strongest factor. In this paper, by revealing the effects of relationship marketing factors and relationship quality on relationship performance, empirically suggested the results which show the same findings as those of previous researches. This result can be a method to establish systematic education systems in places selling basic cosmetic products and in cosmetics companies.