• Journal of Industrial Convergence
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• v.22 no.4
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• pp.11-19
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• 2024

The purpose of this study was to analyze user reviews of running applications using text mining. This study used user reviews of Nike Run Club and Runkeeper in the Google Play Store using the selenium package of python3 as the analysis data, and separated the morphemes by leaving only Korean nouns through the OKT analyzer. After morpheme separation, we created a rankNL dictionary to remove stopwords. To analyze the data, we used TF, TF-IDF and LDA topic modeling in text mining. The results of this study are as follows. First, the keywords 'record', 'app', and 'workout' were identified as the top keywords in the user reviews of Nike Run Club and Runkeeper applications, and there were differences in the rankings of TF and TF-IDF. Second, the LDA topic modeling of Nike Run Club identified the topics of 'basic items', 'additional features', 'errors', and 'location-based data', and the topics of Runkeeper identified the topics of 'errors', 'voice function', 'running data', 'benefits', and 'motivation'. Based on the results, it is recommended that errors and improvements should be made to contribute to the competitiveness of the application.

• Geophysics and Geophysical Exploration
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• v.27 no.2
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• pp.91-107
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• 2024

Single-channel seismic exploration has proven effective in delineating subsurface geological structures using small-scale survey systems. The seismic data acquired through zero- or near-offset methods directly capture subsurface features along the vertical axis, facilitating the construction of corresponding seismic sections. However, substantial noise in single-channel seismic data hampers precise interpretation because of the low signal-to-noise ratio. This study introduces a novel approach that integrate noise reduction and signal enhancement via matrix rank optimization to address this issue. Unlike conventional rank-reduction methods, which retain selected singular values to mitigate random noise, our method optimizes the entire singular value spectrum, thus effectively tackling both random and erratic noises commonly found in environments with low signal-to-noise ratio. Additionally, to enhance the horizontal continuity of seismic events and mitigate signal loss during noise reduction, we introduced an adaptive weighting factor computed from the eigenimage of the seismic section. To access the robustness of the proposed method, we conducted numerical experiments using single-channel Sparker seismic data from the Chukchi Plateau in the Arctic Ocean. The results demonstrated that the seismic sections had significantly improved signal-to-noise ratios and minimal signal loss. These advancements hold promise for enhancing single-channel and high-resolution seismic surveys and aiding in the identification of marine development and submarine geological hazards in domestic coastal areas.

• Journal of Korean Library and Information Science Society
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• v.41 no.2
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• pp.297-315
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• 2010

This study investigates the various statistical data and measures of coauthorship network in the Korean LIS Research Community such as patterns of coauthorship, structural properties, types of cluster, centrality & impact analysis. This issues are mostly addressed through a Social Network Analysis of articles published from 2000 to 2009(10 years) in Korean Library & Information Science major four Journals. The coauthorship network was constructed and various measures of four centralities, PageRank, Effect size were calculated. The results show three implications. 1) There presents a phenomenon of Pareto's law in the articles publishing counts. 2) The top authors based on publishing counts prefer co-work publishing than solo-publishing. 3) The counts of article publishing are significantly correlated with five measures of network and not correlated with the case of power centrality.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.1
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• pp.12-25
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• 2000

To demonstrate possible influences of general bone density on the mandible, histomorphometric analysis was carried out in mandibles and iliac bones and the correlation of the two bone densities was tested. Comparison of bony density in women and men over 60 years in the mandible was carried out too. Quantitative computed tomography(QCT) was taken in cross-section of mandibles at the same site where histomorphometric analysis was peformed to evaluate the reliability of QCT. The analysis included 40 cadavers with no known diseases affecting the bones. The subjects consisted of 15 females and 25 males with a mean age of 60.3 years. Spearman correlation analysis and Wilcoxon rank sum test was performed. The results were as follows. 1. There was statistically no correlation between the mandible and iliac bone in the values of corrected cortical width(CCW), cortical porosity(POR) in cortex, and total bone volume(TBV), mean trabecular plate thickness(MTPT), mean trabecular plate density(MTPD), and mean trabecular plate separation(MTPS) in trabecular bone. 2. Comparison of women and men over 60 years, men had statistically higher bone density than women except fir POR of buccal and lingual cortex, and WTPD of alveolar trabeculae in mandible. 3. There was statistically significant correlation between TBV of trabecular bone and CT No., but not between POR and CT No. in mandible. According to the results above, there was no correlation between mandible and iliac bone density and between mandibular bony density and age. Further studies are required to support the results. A more noninvasive method to be able to measure the bone density of mandible should be developed and it is necessary to accumulate data on the normal values of bone density of mandible according to age and sex. Further study should be carried out about QCT to measure mandibular bony density using QCT.

• The Journal of Korean Physical Therapy
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• v.20 no.4
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• pp.21-28
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• 2008

Purpose: We measured the Oswestry Low Back Pain Disability Index (OLBPDI) and related factors in patients with low back pain. Methods: The sample consisted of 50 patients who received physical therapy at the physical therapy units of the Andong Seoul Sintong Clinic, St. Luke Clinic, and Yeongju Seoul Sintong Clinic in Andong and Yeongju city from October, 2007, to February, 2008. The OLBPDI questionnaire was administered by 5 physical therapists as a cross-sectional study. Student's t-test and analysis of variance (ANOVA/Tukey and Scheffe) were used to analyze OLBPDI score differences. We also used nonparametric statistic analysis (Wilcoxon rank sum test, Median test). Pearson correlation analysis (Spearman correlation analysis) was used to analyze the relationship between OLBPDI and the visual analogue scale (VAS). Multiple regression analysis was performed to determine the effects of independent variables on pain scores as defined by the OLBPDI. Results: The average patient age was 37.1 years (range: 18$\sim$78 years old), and time from onset was 21.7 months (1$\sim$180). OLBPD and VAS scores were 12.70 (3.0$\sim$28.0) and 5.14 (1$\sim$8), respectively. OLBPDI scores were 14.4 in patients taking medicine and 11.57 in those who did not. There was a statistically significant relationship between OLBPDI and VAS (r=0.54, p=0.0001; r=0.55, p=0.0001 by Spearman coefficient). Gender ($\beta$=6.14, p=0.0124), age ($\beta$=-2.01, p=0.0324), weight ($\beta$=0.31, p=0.0222), time from onset ($\beta$=1.54, p=0.0044), and VAS score ($\beta$=1.59, p=0.0004) were significantly associated with OLBPD by multiple regression analysis. Conclusion: Variables associated with OLBPD were gender, age, weight, time from onset, and VAS score. Collecting information on the pain index using OLBPDI was acceptable to patients with low back pain. Further research should explore the pain index by using larger sample sizes and longer follow-up periods.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3575-3581
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• 2016

Background: Cancer survival analysis is an essential indicator for effective early detection and improvements in cancer treatment. This study was undertaken to document colorectal cancer survival and associated prognostic factors in Malaysians. Materials and Methods: All data were retrieved from the National Cancer Patient Registry-Colorectal Cancer. Only cases with confirmed diagnosis through histology between the year 2008 and 2009 were included. Retrieved data include socio-demographic information, pathological features and treatment received. Survival curves were plotted using the Kaplan-Meier method. Univariate analysis of all variables was then made using the Log-rank test. All significant factors that influenced survival of patients were further analysed in a multivariate analysis using Cox' regression. Results: Total of 1,214 patients were included in the study. The overall 3- and 5-year survival rates were 59.1% and 48.7%, respectively. Patients with localized tumours had better prognosis compared to those with advanced stage cancer. In univariate analysis, staging at diagnosis (p<0.001), primary tumour size (p<0.001), involvement of lymph nodes (p<0.001) and treatment modalities (p=0.001) were found to be predictors of survival. None of the socio-demographic characteristics were found to exert any influence. In Cox regression analysis, staging at diagnosis (p<0.001), primary tumour size (p<0.001), involvement of lymph nodes (p<0.001) and treatment modalities (p<0.001) were determined as independent prognostic factors of survival after adjusted for age, gender and ethnicity. Conclusions: The overall survival rate for colorectal cancer patients in Malaysia is similar to those in other Asian countries, with staging at diagnosis, primary tumor size, involvement of lymph node and treatment modalities having significant effects. More efforts are needed to improve national survival rates in future.

• Korean Journal of Radiology
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• v.23 no.10
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• pp.998-1008
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• 2022

Objective: The present study aimed to assess the relationship between incidental abnormalities on thoracic computed tomography (CT) and mortality in a general screening population using a long-term follow-up analysis. Materials and Methods: We retrospectively collected the medical records and CT images of 840 participants (mean age ± standard deviation [SD], 58.5 ± 6.7 years; 564 male) who underwent thoracic CT at a single health promotion center between 2007 and 2010. Two thoracic radiologists independently reviewed all CT images and evaluated any incidental abnormalities (interstitial lung abnormality [ILA], emphysema, coronary artery calcification [CAC], aortic valve [AV] calcification, and pulmonary nodules). Kaplan-Meier analysis with log-rank and z-tests was performed to assess the relationship between incidental CT abnormalities and all-cause mortality in the subsequent follow-up. Cox proportional hazards regression was performed to further identify risk factors of all-cause mortality among the incidental CT abnormalities and clinical factors. Results: Among the 840 participants, 55 (6%), 171 (20%), 288 (34%), 396 (47%), and 97 (11%) had findings of ILA, emphysema, CAC, pulmonary nodule, and AV calcification, respectively, on initial CT. The participants were followed up for a mean period ± SD of 10.9 ± 1.4 years. All incidental CT abnormalities were associated with all-cause mortality in univariable analysis (p < 0.05). However, multivariable analysis further revealed fibrotic ILA as an independent risk factor for all-cause mortality (hazard ratio, 2.52 [95% confidence interval, 1.02-6.22], p = 0.046). ILA were also identified as an independent risk factor for lung cancer or respiratory disease-related deaths. Conclusion: Incidental abnormalities on screening thoracic CT were associated with increased mortality during the long-term follow-up. Among incidental CT abnormalities, fibrotic ILA were independently associated with increased mortality. Appropriate management and surveillance may be required for patients with fibrotic ILA on thoracic CT obtained for general screening purposes.

• Asia pacific journal of information systems
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• v.17 no.4
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• pp.31-59
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• 2007

We frequently use search engines to find relevant information in the Web but still end up with too much information. In order to solve this problem of information overload, ranking algorithms have been applied to various domains. As more information will be available in the future, effectively and efficiently ranking search results will become more critical. In this paper, we propose a ranking algorithm for the Semantic Web resources, specifically RDF resources. Traditionally, the importance of a particular Web page is estimated based on the number of key words found in the page, which is subject to manipulation. In contrast, link analysis methods such as Google's PageRank capitalize on the information which is inherent in the link structure of the Web graph. PageRank considers a certain page highly important if it is referred to by many other pages. The degree of the importance also increases if the importance of the referring pages is high. Kleinberg's algorithm is another link-structure based ranking algorithm for Web pages. Unlike PageRank, Kleinberg's algorithm utilizes two kinds of scores: the authority score and the hub score. If a page has a high authority score, it is an authority on a given topic and many pages refer to it. A page with a high hub score links to many authoritative pages. As mentioned above, the link-structure based ranking method has been playing an essential role in World Wide Web(WWW), and nowadays, many people recognize the effectiveness and efficiency of it. On the other hand, as Resource Description Framework(RDF) data model forms the foundation of the Semantic Web, any information in the Semantic Web can be expressed with RDF graph, making the ranking algorithm for RDF knowledge bases greatly important. The RDF graph consists of nodes and directional links similar to the Web graph. As a result, the link-structure based ranking method seems to be highly applicable to ranking the Semantic Web resources. However, the information space of the Semantic Web is more complex than that of WWW. For instance, WWW can be considered as one huge class, i.e., a collection of Web pages, which has only a recursive property, i.e., a 'refers to' property corresponding to the hyperlinks. However, the Semantic Web encompasses various kinds of classes and properties, and consequently, ranking methods used in WWW should be modified to reflect the complexity of the information space in the Semantic Web. Previous research addressed the ranking problem of query results retrieved from RDF knowledge bases. Mukherjea and Bamba modified Kleinberg's algorithm in order to apply their algorithm to rank the Semantic Web resources. They defined the objectivity score and the subjectivity score of a resource, which correspond to the authority score and the hub score of Kleinberg's, respectively. They concentrated on the diversity of properties and introduced property weights to control the influence of a resource on another resource depending on the characteristic of the property linking the two resources. A node with a high objectivity score becomes the object of many RDF triples, and a node with a high subjectivity score becomes the subject of many RDF triples. They developed several kinds of Semantic Web systems in order to validate their technique and showed some experimental results verifying the applicability of their method to the Semantic Web. Despite their efforts, however, there remained some limitations which they reported in their paper. First, their algorithm is useful only when a Semantic Web system represents most of the knowledge pertaining to a certain domain. In other words, the ratio of links to nodes should be high, or overall resources should be described in detail, to a certain degree for their algorithm to properly work. Second, a Tightly-Knit Community(TKC) effect, the phenomenon that pages which are less important but yet densely connected have higher scores than the ones that are more important but sparsely connected, remains as problematic. Third, a resource may have a high score, not because it is actually important, but simply because it is very common and as a consequence it has many links pointing to it. In this paper, we examine such ranking problems from a novel perspective and propose a new algorithm which can solve the problems under the previous studies. Our proposed method is based on a class-oriented approach. In contrast to the predicate-oriented approach entertained by the previous research, a user, under our approach, determines the weights of a property by comparing its relative significance to the other properties when evaluating the importance of resources in a specific class. This approach stems from the idea that most queries are supposed to find resources belonging to the same class in the Semantic Web, which consists of many heterogeneous classes in RDF Schema. This approach closely reflects the way that people, in the real world, evaluate something, and will turn out to be superior to the predicate-oriented approach for the Semantic Web. Our proposed algorithm can resolve the TKC(Tightly Knit Community) effect, and further can shed lights on other limitations posed by the previous research. In addition, we propose two ways to incorporate data-type properties which have not been employed even in the case when they have some significance on the resource importance. We designed an experiment to show the effectiveness of our proposed algorithm and the validity of ranking results, which was not tried ever in previous research. We also conducted a comprehensive mathematical analysis, which was overlooked in previous research. The mathematical analysis enabled us to simplify the calculation procedure. Finally, we summarize our experimental results and discuss further research issues.

• The Journal of Advanced Prosthodontics
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• v.9 no.3
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• pp.159-169
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• 2017

PURPOSE. The purposes of this study were to evaluate the marginal and internal gaps, and the potential clinical applications of three different methods of dental prostheses fabrication, and to compare the prostheses prepared using the silicone replica technique (SRT) and those prepared using the three-dimensional superimposition analysis (3DSA). MATERIALS AND METHODS. Five Pekkton, lithium disilicate, and zirconia crowns were each manufactured and tested using both the SRT and the two-dimensional section of the 3DSA. The data were analyzed with the nonparametric version of a two-way analysis of variance using rank-transformed values and the Tukey's post-hoc test (${\alpha}=.05$). RESULTS. Significant differences were observed between the fabrication methods in the marginal gap (P < .010), deep chamfer (P < .001), axial wall (P < .001), and occlusal area (P < .001). A significant difference in the occlusal area was found between the two measurement methods (P < .030), whereas no significant differences were found in the marginal gap (P > .350), deep chamfer (P > .719), and axial wall (P > .150). As the 3DSA method is three-dimensional, it allows for the measurement of arbitrary points. CONCLUSION. All of the three fabrication methods are valid for measuring clinical objectives because they produced prostheses within the clinically acceptable range. Furthermore, a three-dimensional superimposition analysis verification method such as the silicone replica technique is also applicable in clinical settings.

• Fashion & Textile Research Journal
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• v.20 no.5
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• pp.533-547
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• 2018

The objective of this study is to examine the perception of golfwear and related trends based on major keywords and associated words related to golfwear utilizing big data. For this study, the data was collected from blogs, Jisikin and Tips, news articles, and web $caf{\acute{e}}$ from two of the most commonly used search engines (Naver & Daum) containing the keywords, 'Golfwear' and 'Golf clothes'. For data collection, frequency and matrix data were extracted through Textom, from January 1, 2016 to December 31, 2017. From the matrix created by Textom, Degree centrality, Closeness centrality, Betweenness centrality, and Eigenvector centrality were calculated and analyzed by utilizing Netminer 4.0. As a result of analysis, it was found that the keyword 'brand' showed the highest rank in web visibility followed by 'woman', 'size', 'man', 'fashion', 'sports', 'price', 'store', 'discount', 'equipment' in the top 10 frequency rankings. For centrality calculations, only the top 30 keywords were included because the density was extremely high due to high frequency of the co-occurring keywords. The results of centrality calculations showed that the keywords on top of the rankings were similar to the frequency of the raw data. When the frequency was adjusted by subtracting 100 and 500 words, it showed different results as the low-ranking keywords such as J. Lindberg in the frequency analysis ranked high along with changes in the rankings of all centrality calculations. Such findings of this study will provide basis for marketing strategies and ways to increase awareness and web visibility for Golfwear brands.