• Journal of Energy Engineering
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• 제26권2호
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• pp.1-11
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• 2017

While they are becoming more viable, synthetic natural gas (SNG) plants, with their high temperatures and pressures, are still heavily dependent on advancements in the state-of-the-art technologies. However, most of the current work in the literature is focused on optimizing chemical processes and process variables, with little work being done on relevant mechanical damage and maintenance engineering. In this study, a combination of pipe system stress analysis and detailed local stress analysis was implemented to prioritize the inspection locations for main pipes of SNG plant in accordance to ASME B31.3. A pipe system stress analysis was conducted for pre-selecting critical locations by considering design condition and actual operating conditions such as heat-up and cool-down. Identified critical locations were further analyzed using a finite element method to locate specific high-stress points. Resultant stress values met ASME B31.3 code standards for the gasification reactor and lower transition piece (bend Y in Fig.1); however, it is recommended that the vertical displacement of bend Y be restricted more. The results presented here provide valuable information for future risk based maintenance inspection and further safe operation considerations.

• Korean Journal of Head & Neck Oncology
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• 제17권2호
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• pp.148-154
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• 2001

Objectives: This study was designed to investigate the significance of serum SCC antigen, CA 19-9, CA 125 level and DNA microsatellite alterations (MSA) as prognostic factors and indicators for recurrences in the pre-treatment and post-treatment state, respectively in head and neck cancer patients. Materials and Methods: 120 patients who received curative treatment for head and neck cancer from 1995 to 2000 were followed up successfully, and were analyzed retrospectively. Thirty healthy subjects served as normal controls. Serum SCC Ag levels were measured by microparticle enzyme immunoassay technique via IMX SCC assay, CA 19-9 levels were measured by CA 19-9 RIA test kit, and CA 125 levels were measured by CA 125 IRMA kit. MSA were identified after PCR amplification. Heterozygosity was considered lost if the ratio of one allele was significantly decreased (>50%) in serum DNA compared with normal DNA from lymphocytes. Results: Preoperative tumor markers were higher in cancer patients than control, but not significant. Postoperative SCC Ag levels were lower than preoperative levels. The SCC Ag levels were remained low in no evidence of disease (NED) group, but increased in locoregional recurrence and distant metastasis group. CA 19-9 and CA 125 levels showed no correlation between levels and recurrences and were not decreased significantly after primary tumor removal. MSA were detected in five out of 21 cases, and highly detected in distant metastasis group. Conclusion: SCC Ag seems to be a helpful serum tumor marker for early detection of recurrence and distant metastasis of head and neck cancer after curative treatment. But, CA 19-9 and CA 125 were not reliable markers for head and neck tumors. MSA were not statistically significant because of the small number of study group. However they may be helpful for screening serum molecular markers for early detection of distant metastasis of head and neck cancers.

• Journal of KIISE:Software and Applications
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• 제35권9호
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• pp.554-561
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• 2008

Prediction technique of user's intention can be used as a post-processing method for reducing the search space of an automatic speech recognizer. Prediction technique of system's intention can be used as a pre-processing method for generating a flexible sentence. To satisfy these practical needs, we propose a statistical model to predict speakers' intentions that are generalized into pairs of a speech act and a concept sequence. Contrary to the previous model using simple n-gram statistic of speech acts, the proposed model represents a dialogue history of a current utterance to a feature set with various linguistic levels (i.e. n-grams of speech act and a concept sequence pairs, clue words, and state information of a domain frame). Then, the proposed model predicts the intention of the next utterance by using the feature set as inputs of CRFs (Conditional Random Fields). In the experiment in a schedule management domain, The proposed model showed the precision of 76.25% on prediction of user's speech act and the precision of 64.21% on prediction of user's concept sequence. The proposed model also showed the precision of 88.11% on prediction of system's speech act and the Precision of 87.19% on prediction of system's concept sequence. In addition, the proposed model showed 29.32% higher average precision than the previous model.

• Journal of Labour Economics
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• 제25권1호
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• pp.47-74
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• 2002

Since the Economic Crisis at the end of 1997, unemployment rate soared up to the record-high 8.6% (February 1999) and, for youth aged 15~29, it was 14.6% (27.8% for aged 15~19). In spite of economic recovery after the crisis, new participants in labor market at the school-to-work transition have faced with difficulties in finding their first jobs and, even further, the ratio of youth at out-of the labor force but not in school has remained at a higher level. It is important to calibrate the negative effects of nonemployment in the short-run as well as in the long-run, but there has been few study on the school-to-work transition in Korea. This study focus on the nonemployment duration to first job after formal education and comparison of its pattern before and after the crisis. A proportional hazard model, considering job prenaration before graduation (21.4% of the sample), with the semi-parametric baseline hazard is applied to the sample from the Korean Labor and Income Panel Survey(1998~2000) and its Youth Supplemental survey(2000). Interview of the Survey is conducted, by the Korea Labor Institute, to the same 5,000 household and 13,738 individual sample, guaranteeing nationwide representativeness. The Supplemental Survey consists of 3,302 young individuals aged 15 to 29 at the time of survey and 1,615 of them who are not in school and provide appropriate information is used for the analysis. The empirical results show that there exists negative duration dependence at the first three or for months at the transition period and no duration dependence since a turning point of the baseline hazard rate and that unemployment rate reflecting labor demand conditions has a positive effect on exiting the nonemployment state, which is inconsistent with a theoretical conclusion. Estimation with samples separated by the date of graduation before and after the crisis shows that the effect of unemployment rate on the hazard was negative for the pre-crisis sample but positive for the post-crisis sample.

• The Journal of the Korea Contents Association
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• 제16권2호
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• pp.633-642
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• 2016

This study looked into Japan's recognition of Korea in early modern era with particular focuses on discourse on Korea and contents in textbooks in those days. In doing so, the topics of nationality, historical recognition, and social aspects in Korea were established and discourse on these topics in educational journals and the contents of textbooks and teaching manuals projected with such discourse were investigated. As for nationality, a strong propensity to negative recognition was clearly observed, represented by the words lazy, enervate, and uncivilized. They defined Korea's history of passive, other-directed nature and described such incompetent national management resulted in negative nationality. Their recognition of Korean history went further away, stating Korea was incapable of maintaining its independence and was a threat to peace of Japan and Asia, hence the forced merger by Japan. The criteria for Japan to assess Korean society were Western civilization and they defined Korean society as a pre-modern society with lower levels of civilization and culture. Discourse in Japan over Korea in early modern era were strongly influenced by Japan's pride as a modern state and its dominating ideology of imperialism and such discussions were spread among students through textbooks and teaching manuals.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제18권7호
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• pp.644-654
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• 2017

Due to globalization and the increasing number of international marriages, Korea has become a multicultural society. In 2012, the Korean Ministry of Education established guidelines for education on multicultural understanding for all K-12 students. The purpose of this study is to understand how education on multicultural understanding is conducted and to provide suggestions for improvements. Based on the six goals of multicultural curriculum in Bennett's conceptual model, this study explores how multicultural education specialists conduct their instructions and how they convey the value of multicultural understanding in public schools. Four multicultural education specialists were recruited, and various qualitative data were collected from pre- and post-interviews and classroom observations. The data were analyzed through thematic analysis. The study findings show that the participants educated elementary students by introducing their own (or spouse's) culture through their traditional clothes, food, and customs. This indicated that they focused mainly on developing multiple historical perspectives and strengthening intercultural competence. However, their current education on multicultural understanding may not help students to increase an awareness of the state of the planet and global dynamics, and to build social action skills. Finally, we suggest that multicultural education should be integrated and infused into national (regular) curricula so that all students can enhance their multicultural understanding.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제19권2호
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• pp.192-201
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• 2018

This study intends to find efficient support methods for small and medium-sized businesses (SMBs) especially in the increasingly important mobile sector. We investigated regarding perceptions of mobile sector-specific support programs and their current state of usage, and perceptions of the new mobile market and the present conditions of each stage of production based on analysis of a survey that included 204 respondents in each SMB to achieve this goal. Concretely, detections through this research were the reasons for non-selection of support businesses, the future prospective mobile business area, the company's own first-preference item and the reason for the preference, plus new mobile areas of willingness to apply the company's own product and its own first-preference item, and the reason for the preference. In addition, we found out covering costs and revenue size of the maximum-revenue product for each stage (from the first to the fourth stage), the kind of a product's execution method connected to the product (e.g. self-production, outsourcing to another company to produce a product), and the execution method for pre-products. We can suggest a policy regarding efficient support alternatives for SMBs related to the mobile sector thanks to these findings.

• Journal of Korean Orthopaedic Sports Medicine
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• 제2권1호
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• pp.37-43
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• 2003

Purpose: This study is to analyse the injury patterns of knee ligament and the factors influencing ligament injuries of knee, and to evaluate the changes of knee function and activity after ski injury. Materials and Methods: Thirty cases of ligament injuries of knee were studied with a questionaire, stress radiographs, magnetic resolution imaging, and physical examination. Mean age was 28.6 years old and mean follow up was 29.6 months. Clinical evaluation of Lysholm knee scoring scale was used for knee function and Tegner activity score was used for activity change after ski injury. Results: The anterior cruciate ligament (ACL) injury accompanied with medial collateral ligament(MCL) injury was most in 11 cases and isolated MCL injury was the next in 9 cases. The common types of injury mechanism were Phantom foot phenomenon (13 cases, 43$\%$) and valgus external rotation injury (12 cases, 40$\%$), which constitute 83$\%$ of all case. At the last follow up, the mean Lysholm score was 93.4 and mean Tegner activity score was 4.2. The reduced Tegner activity score after injury was 1.9. Among several injury groups, the evaluation of knee function and activity was best in the isolated MCL injury group and worst in the ACL injury accompanied with MCL injury group. The factors to influence ski injury were participation to ski class, release of binding, and skiing long time more than 2 hours. Conclusions: Lysholm score at last follow up revealed good grading, but sports activity after ski injury was reduced when compared with pre-injury state. It seems to need a active, systemic sports rehabilitation program after sports injury.

• Journal of the Korean Institute of Landscape Architecture
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• 제34권3호
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• pp.104-119
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• 2006

The eastern rear business complex of the Gwangyang Harbor (second stage) has undergone the 'alternative bid' process by which a construction company is selected based on their suggestions for an alternative plan and the bid for the construction expenses is based on the previously completed original plan, thereby implicitly accepting the arrangement and scale of the park which was presented in the original plan. It is possible, however, that the concept and plan of each park needs to be approached in a new way within the extent of given design guidelines. This study focuses on the alternative plan process and the Symbol Park (the second neighborhood park) and Waterfront Park (the third neighborhood park) among the five neighborhood parks in the eastern rear business complex (second stage). These two parks provide scale and function for the structure of the park and greenways system at the eastern rear complex. The neighboring waterway is a significant resource for emphasizing the pre-development features of the site. The alternative plan process focuses on determining the resources for the park's plan based on the environmental analyses of the site and utilizing the results. That is, through an analysis of the current state, all available resources are determined and the facilities and activities are derived based on these results. By this, Symbol Park and Waterfront Park reflect the regional features of the eastern rear complex, and these parks will feasibly perform the role of the region's key parte. The limit of this study is the fact that there is no chance for landscape architecture to actively play a role in the creation of the master plan, land utilization plan, and plan for the complex. Therefore there is a problem that the function scale and location of the park are not distributed appropriately in the rear complex. Also the plan for protecting the waterway's shore, a significant resource, only considers the structural stability of the engineering works, degrading the visual and ecological quality. These experiences will be used as a case for further designing the industrial complex and for the resulting park plan.

• Polymer(Korea)
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• 제34권1호
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• pp.25-31
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• 2010

Polymer core and metal shell composite particles have been prepared by the electroless nickel plating on the surface of monodisperse polystyrene microspheres. Various sizes of polystyrene particles with highly monodisperse state could be synthesized by controlling the dispersion medium in dispersion polymerization. Electroless nickel plating was performed on the polystyrene particle with diameter of $3.4\;{\mu}m$. The morphology of polystyrene/nickel composite particles was investigated to see the effect of the plating conditions, such as the $PdCl_2$ and glycine concentrations and the dropping rate of nickel plating solution, on nickel deposition. With $PdCl_2$ and glycine concentrations at more than 0.4 g/L and 1 M, respectively, more uniform nickel layer and less precipitated nickel aggregates were formed. At the given plating time of 2 h, the same amount of plating solution was introduced by varying the dropping rate. Though the effect of dropping rate on particle morphology was not noticeable, the dropping rate of 0.15 mL/min for 60 min showed rather uniform plating.