• Korean Journal of Computational Design and Engineering
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• v.17 no.2
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• pp.123-131
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• 2012

The requirements for computational resources to perform the structural analysis are increasing rapidly. The size of the current analysis problems that are required from practical industry is typically large-scale with more than millions degrees of freedom (DOFs). These large-scale analysis problems result in the requirements of high-performance analysis codes as well as hardware systems such as supercomputer systems or cluster systems. In this paper, the pre- and post-processing system for supercomputing based large-scale structural analysis is presented. The proposed system has 3-tier architecture and three main components; geometry viewer, pre-/post-processor and supercomputing manager. To analyze large-scale problems, the ADVENTURE solid solver was adopted as a general-purpose finite element solver and the supercomputer named 'tachyon' was adopted as a parallel computational platform. The problem solving performance and scalability of this structural analysis system is demonstrated by illustrative examples with different sizes of degrees of freedom.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.5
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• pp.397-411
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• 2021

This systematic review aimed to assess the effect of premedication on postoperative pain after root canal treatment in vital teeth. Five electronic databases were searched for randomized clinical trials, and two independent reviewers selected eligible studies, extracted data, and assessed the quality of studies using the Cochrane Risk of Bias tool. Meta-analysis was conducted using the random-effects model, and the pooled effect estimate of the standardized mean difference (SMD) between premedication and placebo was calculated. Subgroup analysis was conducted based on the class and route of the drug. Studies with a high risk of bias were excluded from the sensitivity analysis. Ten trials satisfied the inclusion criteria, of which eight were included in the meta-analysis. Premedication was more effective in reducing postoperative pain than placebo at 6 hours (SMD = -1.00; 95% confidence interval [CI] = -1.33 to -0.66), 12 hours (SMD = -0.80; 95% CI = -1.05 to -0.56), and 24 hours (SMD = -0.72; 95% CI = -1.02 to -0.43). The results of the sensitivity analysis confirmed the findings of the primary analysis. Based on these results, it can be concluded that premedication is effective in reducing postoperative pain in teeth with irreversible pulpitis. However, additional quality studies are required for further validation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1145-1152
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• 2016

A construction post evaluation is introduced to provide information that can be used for similar construction projects in the future through the evaluation of the efficiency of a public construction project and the verification of the appropriateness of the project results. However, it is not widely used due to a lack of awareness of the method. For this reason, the aim of this study is to provide a basic frame that can be utilized as a reference for a similar project in the future based on the construction post evaluation. More specifically, a more effective analysis method for the construction post evaluation is proposed and then an exemplary analysis is performed based on the method. The paper analyzes 293 cases stored in construction CALS. Construction cost growth rates of railway projects are tend to be greater than other project types like highway, expressway, and harbour. Then, construction schedule grwoth rates of expressway are greater than others. This is expected to provide useful information for a future project, and serve as a basic frame. Moreover, it is also meaningful that a project can be analyzed from different perspectives through the construction post evaluation.

• The Journal of the Korea Contents Association
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• v.12 no.7
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• pp.147-155
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• 2012

This study is to analyze the difference of the post-viewing emotion and behavior of the audience at a dance performance by general characteristics of the audience. To attain the goal of the study described above paragraphs, the audience of dance performance located in Seoul and Kyoungki-Do was set as a collected group. Then, using the convenience sampling method, finally drew out and analyzed 280 people in total. statistic analysis techniques were used SPSS 18.0 program. Based on the statistical methods above, we had the result of data analysis as follows; First, among the general characteristics(job, viewing frequency, dance experience, and genre), had significantly effect on the post-viewing emotion(positive emotion, satisfaction) Second, among the general characteristics(job, viewing frequency, dance experience, and genre), all the factors had significantly effect on post-viewing behaviors(researching, respectating intention).

• The Journal of Fisheries Business Administration
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• v.42 no.2
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• pp.1-14
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• 2011

We try to find the determinants of fisheries firms' capital structure during the years from 1992 to 2007 in this paper. We also have a comparative analysis of capital raising behavior in pre and post-IMF financial crisis. Regression analysis is used for this empirical study. Dependent variable is leverage ratio and independent variables are firm size, operating risk, proportion of tangible asset, non-debt tax shield effect, sales growth ratio, profitability and dummy variable. We compared the characteristics of fisheries industry with that of manufacturing industy. The determinants of fisheries firms' capital structure and correlation between pre and post-IMF financial crisis are roughly same as the hypothses except a little difference. As a peculiar difference, corrlation between fisheries firms' operating risk and leverage ratio is (+) in the pre-IMF financial crisis, but (-) in the post-IMF financial crisis. Proportion of tangible asset has a (+) correlation with leverage ratio in pre and post-IMF financial crisis, but in case of manufacturing industy, (-) correlation shows in the pre-IMF financial crisis. Because, in the pre-IMF financial crisis, high proportion of tangible asset doesn't play a role of a collateral, but only increase the bankruptcy probability. Non-debt tax shield effect and leverage ratio have (-) correlation in all industry and all period, but only (+) correlation in case of fisheries industry in the pre-IMF financial crisis. Sales growth ratio has no significant relationship with leverage ratio in fisheries industry, and this is not coincide with our hypothsis. We have a limitation of the sample size of fisheries firms and sample period in this study. Further study is required to classify the fisheries industry with in-shore fisheries, deep sea fisheries and cold storage industry.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.4
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• pp.809-817
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• 2012

One of the OSI 7 Layer DDoS Attack, HTTP POST DDoS can deny legitimate service by web server resource depletion. This Attack can be executed with less network traffic and legitimate TCP connections. Therefore, It is difficult to distinguish DDoS traffic from legitimate users. In this paper, I propose an anomaly HTTP POST traffic detection algorithm and http each page Content-Length field size limit with defense method for HTTP POST DDoS attack. Proposed method showed the result of detection and countermeasure without false negative and positive to use the r-u-dead-yet of HTTP POST DDoS attack tool and the self-developed attack tool.

• Structural Engineering and Mechanics
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• v.13 no.5
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• pp.557-568
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• 2002

For the evaluation of the capability of a tubular member of an offshore structure to absorb the collision energy, a simple method can be employed for the collision analysis without performing the detailed analysis. The most common simple method is the rigid-plastic method. However, in this method any characteristics for horizontal movement and rotation at the ends of the corresponding tubular member are not included. In a real structural system of an offshore structure, tubular members sustain a certain degree of elastic support from the adjacent structure. End fixity has influences in the behaviors of a tubular member. Three-dimensional FEM analysis can include the effect of end fixity fully, however in viewpoints of the inherent computational complexities of the 3-D approach, this is not the recommendable analysis at the initial design stage. In this paper, influence of end fixity on the behaviors of a tubular member is investigated, through a new approach and other approaches. A new analysis approach that includes the flexibility of the boundary points of the member is developed here. The flexibility at the ends of a tubular element is extracted using the rational reduction of the modeling characteristics. The property reduction is based on the static condensation of the related global stiffness matrix of a model to end nodal points of the tubular element. The load-displacement relation at the collision point of the tubular member with and without the end flexibility is obtained and compared. The new method lies between the rigid-plastic method and the 3-demensional analysis. It is self-evident that the rigid-plastic method gives high strengthening membrane effect of the member during global deformation, resulting in a steeper slope than the present method. On the while, full 3-D analysis gives less strengthening membrane effect on the member, resulting in a slow going load-displacement curve. Comparison of the load-displacement curves by the new approach with those by conventional methods gives the figures of the influence of end fixity on post-yielding behaviors of the relevant tubular member. One of the main contributions of this investigation is the development of an analytical rational procedure to figure out the post-yielding behaviors of a tubular member in offshore structures.

• The Journal of the Convergence on Culture Technology
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• v.8 no.2
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• pp.209-215
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• 2022

In this study, detailed factors of public sentiment toward the 'post-corona new normal' were examined through social media big data sentiment analysis. Thus, it is to provide basic data to preemptively cope with the post-COVID-19 era. For data collection and analysis, the emotional analysis program of 'Textom', a big data analysis program, was used. The data collection period is one year from October 5, 2020 to October 5, 2021, and the collection channels are set as blogs, cafes, Twitter, and Facebook on Daum and Naver. The original data edited and refined a total of 3,770 collected texts from this channel were used for this study. The conclusion is as follows. First, there is a high level of interest and liking for the 'post-corona new normal'. In other words, it can be seen that optimism such as daily recovery, technological growth, and expectations for a new future took the lead at 77.62%. Second, negative emotions such as sadness and rejection are 22.38% of the total, but the intensity of emotions is 23.91%, which is higher than the ratio, suggesting that these negative emotions are intense. This study has a contribution to the detailed factor analysis of the public's positive and negative emotions through big data analysis on the 'post-corona new normal'.

• Journal of Korean Elementary Science Education
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• v.35 no.2
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• pp.216-228
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• 2016

The purpose of this study was to analyze pre-school teachers' observation experience and their pre and post degrees of preferences in observing underground and water living things, fungus, insects, flowerless plants and sea lives. Based on the analysis, their pre-observation experience in living things were insects, ocean creatures, underground living things, flowerless plants, fungus and water living things in order. The degree of preferences in flowerless plans based on their gender, the female pre-service teachers showed higher scores than the average in both pre and post test. The male, however, responded higher scores in underground living things in both tests. Their background such as liberal arts or science or arts and physical major affected their preferences scores in water living things, insects and flowerless plans in the post test, and the science major pre-service teachers showed the highest degree of preferences in insects among the liberal arts, science or arts and physical major pre-teachers in the post test. In conclusion, there were different degree of their preferences affected by the pre observation experience, gender difference, their present majors such as the liberal arts, science or arts and physical major, the categories of living things but not in their high school background such as liberal arts or science.

• Journal of Korean Academy of Rural Health Nursing
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• v.10 no.2
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• pp.75-92
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• 2015

Purpose: The purpose of this study was to examine the effects of an integrated health promotion program provided by one community health post by comparing this program with more traditional health promotion programs provided by other institutions. Methods: The participants in this study were 110 selected local residents from I city. Of them, 55 residents participated in the integrated health promotion program in the community health post, and the other 55 participated in a program at another institution. SPSS 21.0 was used for descriptive analysis. Result: Scores for program effects, satisfaction level, quality of life related to health and depression were higher for the integrated health promotion program offered by the community health post compared to health promotion programs of the other institution. The differences were statistically significant. Conclusion: The findings of the study indicate that the integrated health promotion program can be helpful for community health posts in being successful in future plans to meet the needs of residents. Use of this program will also contribute to the development of community health posts but sustained research efforts need to be channeled into these programs.