• Korean Journal of Radiology
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• v.21 no.7
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• pp.812-828
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• 2020

Objective: To provide an evidence-based guide for the MRI interpretation of complete tumor response after neoadjuvant chemoradiation therapy (CRT) for rectal cancer using visual assessment on T2-weighted imaging (T2) and diffusion-weighted imaging (DWI). Materials and Methods: PubMed MEDLINE, EMBASE, and Cochrane Library were searched on November 28, 2019 to identify articles on the following issues: 1) sensitivity and specificity of T2 or DWI for diagnosing pathologic complete response (pCR) and the criteria for MRI diagnosis; 2) MRI alone vs. MRI combined with other test(s) in sensitivity and specificity for pCR; and 3) tests to select patients for the watch-and-wait management. Eligible articles were selected according to meticulous criteria and were synthesized. Results: Of 1615 article candidates, 55 eligible articles (for all three issues combined) were identified. Combined T2 and DWI performed better than T2 alone, with a meta-analytic summary sensitivity of 0.62 (95% confidence interval [CI], 0.43-0.77; I² = 80.60) and summary specificity of 0.89 (95% CI, 0.80-0.94; I² = 92.61) for diagnosing pCR. The criteria for the complete response on T2 in most studies had the commonality of remarkable tumor decrease to the absence of mass-like or nodular intermediate signal, although somewhat varied, as follows: (near) normalization of the wall; regular, thin, hypointense scar in the luminal side with (near) normal-appearance or homogeneous intermediate signal in the underlying wall; and hypointense thickening of the wall. The criteria on DWI were the absence of a hyperintense signal at high b-value (≥ 800 sec/mm²) in most studies. The specific algorithm to combine T2 and DWI was obscure in half of the studies. MRI combined with endoscopy was the most utilized means to select patients for the watch-and-wait management despite a lack of strong evidence to guide and support a multi-test approach. Conclusion: This systematic review and meta-analysis provide an evidence-based practical guide for MRI assessment of complete tumor response after CRT for rectal cancer.

• Journal of the Korean Society for information Management
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• v.35 no.3
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• pp.41-75
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• 2018

The purpose of this study is to analyze the characteristics of Korean media on the topic of archives & records management based on time-series analysis. In this study, from January, 1999 to June, 2018, 4,680 news articles on archives & records management topics were extracted from BigKinds. In order to examine the characteristics of the media coverage on the archives & records management topic, this study was analyzed to the difference of the press coverage by period, subject, and type of the media. In addition, this study was conducted word-frequency based content analysis and semantic network analysis to investigate the content characteristics of media on the subject. Based on these results, this study was analyzed to the differences of media coverage by period, subject, and type of media. As a result, the news in the field of records management showed that there was a difference in the amount of news coverage and news contents by period, subject, and type of media. The amount of news coverage began to increase after the Presidential Records Management Act was enacted in 2007, and the largest amount of news was reported in 2013. Daily newspapers and financial newspapers reported the largest amount of news. As a result of analyzing news reports, during the first 10 years after 1999, news topics were formed around the issues arising from the application and diffusion process of the concept of archives & records management. However, since the enactment of the Presidential Records Management Act, archives & records management has become a major factor in political and social issues, and a large amount of political and social news has been reported.

• Information Systems Review
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• v.13 no.3
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• pp.141-163
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• 2011

The advancement of information technologies including the Internet has affected the way of social information processing as well as brought about the paradigm shift to the information society. Accordingly, it is very important to study the process of social information processing over the digital media through which social information is generated, distributed, and led to social consensus. In this study, we analyze the mechanism of social information processing, identify a process model of social consensus and institutionalization of the results, and finally propose a set of information processing characteristics on the internet media. We deploy the ethnographic approach to analyze the meaning of group behavior in the context of society to analyze two major events which happened in Korean society. The formation process of social consensus is found to consist of 5 steps: suggestion of social issues, selective reflection on public opinion, acceptance of the issues and diffusion, social consensus, and institutionalization and feedback. The key characteristics of information processing in the Internet is grouped into proactive response to an event, the changes in the role of opinion leader, the flexibility of proposal and analysis, greater scalability, relevance to consensus making, institutionalization and interaction. This study contributes to the literature by proposing a process model of social information processing which can be used as the basis for analyzing the social consensus making process from the social network perspective. In addition, this study suggests a new perspective where the utility of the Internet media can be understood from the social information processing so that other disciplines including politics, communications, and management can improve the decision making performance in utilizing the Internet media.

• Journal of Korea Technology Innovation Society
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• v.22 no.2
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• pp.242-264
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• 2019

This study focuses on considering the factors affecting the user intention to adopt an intelligent service - A.I. speaker services. Currently there can be a considerable difference between the expectation and the realized diffusion of IT-based intelligent services. This study aims to find out this gap based on the idea of diver previous researches including TAM and UTAUT studies and to identify the direct and indirect effects of diverse factors such as security issues, perceived time pressure, service innovativeness, and the experience of these IT-based intelligent services. And this study considers the expected impact of perceived time pressure factor on the user acceptance of A.I. speaker services. In analysis results, not only the traditional factors such as the perceived usefulness and the hedonic/utilitarian motives but also the perceived time pressure, the perceived security issues, and the experience of the services should be considered as meaningful factors to affect the users adopting A.I. speaker services.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.28-37
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• 2020

This study was conducted to propose measures to improve crisis response to environmental issues by analyzing the news big data on the 'tap water larvae' situation and identifying related major keywords and topics. To accomplish this, 1,975 cases of 'tap water larvae' reported between July 13 to August 31, 2020 were divided into three periods and analyzed using topical modeling techniques. The analysis output 15 topics for each period. According to the result, the 'tap water larvae' incident, as reported in the media, is divided into the occurrence, diffusion, and rectification stages. The government's response and civilian risk consciousness and reaction could also be seen. Based on the result, the following measures to respond to environment risk is proposed. First, it is necessary to explore the various intertwined context with the 'tap water larvae' incident at its core and develop responsiveness to environmental problems through education which forms integrated views. Second, a role to monitor the environment must be implemented and civilian-participated environmental information must be shared through the application of internet communities. Third, the cultivation and deployment of environmental communicators who provide and communicate fast and accurate environment information is required. This study, as the first in Korea to use the topic modeling analysis method based on big data related to 'tap water larvae', has academic significance in that it has empirically and systematically analyzed environmental issues which appear as unstructured data. It also political significance as it suggests ways to improve environmental education and communication.

• Journal of Environmental Health Sciences
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• v.39 no.4
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• pp.360-368
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• 2013

Objectives: Phthalates are used in a large variety of products including as coatings of pharmaceutical tablets, film formers, stabilizers, dispersants, emulsifying agents, and suspending agents. They have been the subject of great public concern in recent years. The extensive uses of this material have attracted attention and issues regarding its safety have been raised. Methods: In this study, three types of phthalate skin permeation were studied using matrixes such as ointments, creams and lotions in vitro. The absorption of phthalate diesters [Dimethyl phthalate (DMP), Di-n-propyl phthalate (DPP) and Di-n-pentyl phthalate (DNPP)] using film former has been measured in vitro through rat skin. Epidermal membranes were set up in Franz diffusion cells and their permeability to PBS measured in order to establish the integrity of the skin before the phthalates were applied to the epidermal surface. Results: Absorption rates for each phthalate ester were determined and permeability assessment made to quantify any irreversible alterations in barrier function due to contact with the esters. Types of phthalate in vitro experimental results quickly appeared in the following order DMP > DPP ${\geq}$ DNPP. Conclusions: In the experimental results, lotion> cream> ointment, and the permeation rate of lotion with a great amount of moisture was the fastest. Skin permeation rate is generally influenced by the chemical characteristics of a given chemical, such as molecular weight and lipophilicity. As the esters became more lipophilic and less hydrophilic, the rate of absorption decreased.

• Journal of Information Technology Services
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• v.12 no.2
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• pp.387-410
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• 2013

Due to the development of information technology, Convergence and Creative Economy became hot issues. For example, products become more intelligent and services are likely to be connected and integrated around core services or provided as bundle solution. Meanwhile products and services are integrated in the context of mutual supplementation, which leads to Servitization of Products and Productization of Services in many industries. Previous studies have addressed Convergence with different terms and definitions such as Convergent, Multicategory Multifunctional Product, Clouding Service, Bundle and so on from one perspective such as consumers, suppliers or technology according to a wide range of academic approaches. Thus, this study attempted to suggest the most typical convergence products released in the convergence environment and categorize those products. Furthermore, this study has pointed out the problems in the New Product Development Framework discussed in the studies on marketing by taking the situation of the public sector into account and then suggested "New Service Development Framework in the Public Sector" that are different from traditional e-Gov. approach basically and will enable the government to create public information service and provide them to enterprises or citizens. It also emphasized the importance of Business Conceptualization Stage in the framework; argued that there is a necessity of an integrative study from the perspective of technology on the basis of the approach from the perspective of marketing and Policy such as a study of consumer behaviors, design and marketing channel and Policy Integration for the development and dissipation; and furthermore suggested the cases-the development/Diffusion of Transportation Card Service in Seoul and CFC (Call for Collaboration) in Singapore-in order to verify the framework. There is a need to supplement New Service Development Framework so it is able to reflect the distinct characteristics of the public sector from the academic perspective and be used as practical guidelines for SI (System Integration) business to shift into IT Service business. Last but not the least, this study has suggested the limitations and the directions for the future studies.

• Corrosion Science and Technology
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• v.20 no.4
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• pp.204-209
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• 2021

Corrosion failure analysis of the flow plate, which is one of the accessories of the plate heat exchanger in a district heating system, was performed. The flow plate is made of 316 stainless steel, and water at different temperatures in the flow plate exchanges heat in a non-contact manner. The flow plate samples in which water mixing issues occurred were collected. Corrosion-induced pits, oxides, and contaminants were observed at locations where two plates are regularly in contact. The EDS analysis of the surface oxides and contaminants revealed that they were composed of carbon, silicon, and magnesium, which came from chemical adhesives. The IC/ICP analyses showed that the concentration of chloride ions was 30 ~ 40 ppm, which was not sufficient to cause corrosion of stainless steel. In the crevice, a local decrease in dissolved oxygen occurs along with an increase in chloride ions, thus forming an acidic environment. These environments destroyed the passive film of stainless steel, resulting in pits. Moreover, contaminants formed a narrower gap between the two metal plates and inhibited the diffusion of ions, thereby accelerating crevice corrosion.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.163-171
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• 2021

This study aimed to investigate the main characteristics of the COVID-19 vaccine-related videos spread on YouTube and differences in user responses in the infodemic situation caused by COVID-19. As a result of content analysis of 579 videos related to the COVID-19 vaccine, it was found that all of the false information was written by individual channels. Institutions, organizations, media companies, and government channels reported spread of false information as well as fact-oriented reporting. The progressive channel had a high percentage of positive sentiment in favor of vaccination, and the conservative channel had a high percentage of negative emotion against vaccination. After the vaccination started, the number of videos on government channels increased, and it was found that the number of videos with positive emotions increased. Results of regression analysis of video characteristics that affect the number of likes indicated that personal expert videos and videos from progressive channels received more likes. Combining the research results, we propose a plan to promote government policies regarding the COVID-19 vaccine using social media.

• Journal of the Korean Ceramic Society
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• v.55 no.3
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• pp.244-260
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• 2018

Issues in the electrical characterization of semiconducting photoanodes in a photoelectrochemical (PEC) cell, such as the cell geometry dependence, scan rate dependence in DC measurements, and the frequency dependence in AC measurements, are addressed, using the example of a $TiO_2$ photoanode. Contrary to conventional constant phase element (CPE) modeling, the capacitive behavior associated with Mott-Schottky (MS) response was successfully modeled by a Havriliak-Negami (HN) capacitance function-which allowed the determination of frequency-independent Schottky capacitance parameters to be explained by a trapping mechanism. Additional polarization can be successfully described by the parallel connection of a Bisquert transmission line (TL) model for the diffusion-recombination process in the nanostructured $TiO_2$ electrode. Instead of shunt CPEs generally employed for the non-ideal TL feature, TL models with ideal shunt capacitors can describe the experimental data in the presence of an infinite-length Warburg element as internal interfacial impedance - a characteristic suggested to be a generic feature of many electrochemical cells. Fully parametrized impedance spectra finally allow in-depth physicochemical interpretations.