• Journal of Labour Economics
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• v.24 no.1
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• pp.97-124
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• 2001

Co-residence is a type of intergenerational private transfers of resources: money, time and space. Adult daughters and their elderly parents decide to co-reside, depending on their utility levels before and after co-residence that mainly depend on the health status of the elderly. Therefore, co-residence implies positive net benefits to both parties in the sense that, when they co-reside, elderly parents share childcare and adult daughter provide elderly care. In other words, formal (paid) care can be substituted with informal (unpaid) one. Both marriage and giving births are considered as the major obstacles to labor market attachment of women who bear burdens of home production and childcare. Co-residence can be a solution for married women to avoid career interruption by sharing burdens with their elderly parents. However, most previous studies using the U.S. data on intergenerational private transfers focused on elderly care and have concluded that they reduce government expenditures associated with public subsidies to the elderly. This study focuses on adult daughters and it examines effects of co-residence on labor supply of married women in Korea, who face limited formal childcare programs in terms of both quantity and quality. It applies the Tobit model of married women's labor supply to the data from the Second Wave of the Korean Labor and Income Panel Survey( 1999), in order to investigate effects of co-residence and the work and health status of the co-residing elderly as well as their own health status. Four specifications of the empirical model are tested that each includes co-residence with elderly parents, their gender, or their work and health status. Estimation results show that co-residence, co-residence with female elderly, and co-residence with not-working female elderly have significant positive effects on labor supply of married women while poor health status of co-residing female elderly does not bring about any negative effects. However, co-residence with male elderly, regardless of their work and health status, has no significant effect The results indicate that co-residence is closely related to sharing of home production among female elderly and adult daughters who are married and, through intergenerational private transfers of resources in terms of time, it helps women avoid career interruption.

• Tunnel and Underground Space
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• v.23 no.1
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• pp.1-12
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• 2013

Enhanced oil recovery (EOR) technology coupled with underground carbon dioxide sequestration is introduced. $CO_2$ can be injected into an oil reservoir in order to enhance oil production rate and $CO_2$ EOR can be turned into CCS in a long term sense. Coupling $CO_2$ EOR with CCS may secure a large scale and consistent $CO_2$ source for EOR, and the $CO_2$ EOR can bring an additional economic benefit for CCS, since the benefit from enhanced oil production by $CO_2$ EOR will compensate costs for CCS implementation. In this paper, we introduced the characteristics of $CO_2$ EOR technology and its market prospect, and reviewed the Weyburn $CO_2$ EOR project which is the first large-scale $CO_2$ EOR case utilizing an anthropogenic $CO_2$ source. We also introduced geotechnical elements for a successful and economical implementation of $CO_2$ EOR with CCS and they were a miscroseismic monitoring during and after injection of $CO_2$, and determination of minimum miscible pressure (MMP) and maximum injection pressure (MIP) of $CO_2$.

• Asia pacific journal of information systems
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• v.18 no.1
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• pp.117-144
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• 2008

Lots of virtual communities and online businesses presently derive their primary sources of revenues through advertising, but nevertheless are plagued with marginal profitability though they might possess a significant user base. In the light of the need for an efficacious business model, there have been recent insights of an online community in particular reaping profits through an innovative and lucrative revenue generation method that earns by selling digital items. There have been some obvious evidences (e.g., Cyworld, SecondLife, Habo Hotel, etc.) that online communities can be profitable through their unique business model of selling digital items. However, there is lack of understanding about the motivation of purchasing digital items. This study tries to identify the main motivators of digital item purchases based on social/individual identity theory and self-presentation theory. "Digital items", otherwise known as "virtual assets", may include online avatars, accessories for the avatars, decorative ornaments like furniture, digital wallpapers, skins, background music and virtual weapons used for Internet games. These digital items are employed by users for representation and articulation in the online space, especially to create and enhance their online profiles in web pages and games. Prices for digital items typically range from a few cents to a few dollars each. Based on the theoretical framework like social identity theory and self-presentation theory, we developed the research model and proposed seven hypotheses. An analysis of 225 members of Cyworld found that digital item purchase intention in virtual world is affected by both members' need for self-presentation and need for affiliation. We also found that the need for self-presentation is significantly increased by innovativeness of members, community group norm, and community involvement. We concluded that the need for self-presentation could be a key variable for profitable business model in online community service industry. However, neither individual self-efficacy nor the need for affiliation significantly influenced the need for self-presentation which triggers purchase intention of digital items. In term of the theoretical and practical contribution, this study can be a pioneering empirical research that investigates the purchase intention of digital items based on social identity theory and self-presentation theory in the online context. Also, the findings of our study are valuable and practical for practitioners in the market who wish to adopt or improve the business model of selling digital items in an online community. From the findings, it can be seen that innovativeness of users, community group norm, and community involvement are three significant factors that influence need for self-presentation of users which ultimately leads to their intentions to buy digital items. These findings put forth that virtual community providers and online businesses selling digital items should prioritize their efforts and focus on these three factors if they want to increase the sales of these digital items and generate greater revenues. This study provides important implications for academic researchers and practitioners to understand why the community members pay money for their digital items in virtual world and how the practitioners can increase the sales of digital items in an online community. A couple of limitations of the study and future research directions are also discussed.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.390-397
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• 2010

Residual solvents in foods are defined as organic volatile chemicals used or produced in manufacturing of extracts or additives, or functional foods. The solvents are not completely eliminated by practical manufacturing techniques and they also may become contaminated by solvents from packing, transportation or storage in warehouses. Because residual solvents have no nutritional value but may be hazardous to human health, there is a need to remove them from the final products or reduce their amounts to below acceptable levels. The purpose of this study was to develop and evaluate an analytical method for the screening of residual solvents in health functional foods. Furthermore, the aim of this study was to constitute a reasonable management system based on the current state of the market and case studies of foreign countries. Eleven volatile solvents such as MeOH, EtOH, trichloroethylene and hexane were separated depending on their column properties, temp. and time using Gas Chromatography (GC). After determining the GC conditions, a sample preparation method using HSS (Head Space Sampling) was developed. From the results, a method for analyzing residual solvents in health functional foods was developed considering matrix effect and interference from the sample obtained from the solution of solvents-free health functional foods spiked with 11 standards solutions. Validation test using the developed GC/HSS/MS (Mass Spectrometry) method was followed by tests for precision, accuracy, recovery, linearity and adequate sensitivity. Finally, examination of 104 samples grouped in suits was performed by the developed HSS/GC/MS for screening the solvents. The 11 solvents were isolated from health functional foods based on vapor pressure difference, and followed by separation within 15 minutes in a single run. The limt of detection (LOD), limit of quantification (LOQ), recovery and coefficient of variation (C.V.) of these compounds determined by the HSS/GC/MS were found to be 0.1 pg/mL, 0.1-125 pg/g, 51.0-104.6%, and less than 15%, respectively. Using the developed HSS/GC/MS method, residual solvent from 16 out of 104 health functional products were detected as a EtOH. This method therefore seems t o be a valuable extension ofanalytical method for the identification of residual solvents in health functional food.

• Journal of Korean Society of Transportation
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• v.23 no.3 s.81
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• pp.35-47
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• 2005

This paper is to review a literature concerning Bus Transit Route Network Design(BTRNDP), to describe a future study direction for a systematic application for the BTRNDP. Since a bus transit uses a fixed route, schedule, stop, therefore an approach methodology is different from that of auto network design problem. An approach methodology for BTRNDP is classified by 8 categories: manual & guideline, market analysis, system analytic model. heuristic model. hybrid model. experienced-based model. simulation-based model. mathematical optimization model. In most previous BTRNDP, objective function is to minimize user and operator costs, and constraints on the total operator cost, fleet size and service frequency are common to several previous approach. Transit trip assignment mostly use multi-path trip assignment. Since the search for optimal solution from a large search space of BTRNDP made up by all possible solutions, the mixed combinatorial problem are usually NP-hard. Therefore, previous researches for the BTRNDP use a sequential design process, which is composed of several design steps as follows: the generation of a candidate route set, the route analysis and evaluation process, the selection process of a optimal route set Future study will focus on a development of detailed OD trip table based on bus stop, systematic transit route network evaluation model. updated transit trip assignment technique and advanced solution search algorithm for BTRNDP.

• Journal of the Korean association of regional geographers
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• v.19 no.3
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• pp.454-475
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• 2013

In 2011, Daegu hosted the International Association of Athletics Federation Championships and attempted to use this event strengthen its global profile. Organizers hoped Daegu 2011 would strengthen knowledge about Daegu internationally and help the city overcome recent economic stagnation by bolstering tourism and investment on the global scale. Written from the perspective of a foreigner living in Korea, this interpretive article uses mixed-method cultural geographic analysis to evaluate the momentum Daegu 2011 produced in these directions. The article draws on a tripartite "territorialisation" approach to mega-event tourism's production of space, focusing on representational efforts during the approach to the championships and the event itself. Promotional materials receive particular attention. Interviews with international tourists during 2011 strengthen conclusions drawn from analysis of promotional materials. After reviewing relevant conceptual literature, Daegu's history, and the background of Daegu 2011, the article devotes three subsections to analysis. The first uses critical discourse analysis of a key promotional video to argue that Daegu's self-promotions betrayed insecurity about the city's place within the global tourism market. A second analysis subbsection finds that additional promotional materials did not fully overcome that problem. These materials also produced an overload of Daegu images and aspirations. The third subsection further develops these arguments, pointing to a partial mismatch between images emphasized by promotions and experiences available in the tourism landscape. This subsection also argues that while Daegu 2011 undoubtedly produced positive effects for the city, key challenges remain if Daegu will be placed on the map of globally acknowledged cities.

• Informatization Policy
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• v.27 no.1
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• pp.92-114
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• 2020

The purpose of this study is to analyze people's motivations to use the National Petition service of CheongWaDae, the Presidential Office of Korea. The online space has been used as a testbed of deliberative democracy. In fact, a wide variety of public opinions are being formed and gaining sympathy through the E-Petitions and Daum's Agora. In this regard, President Moon's government launched a petition site to gather public opinions. For any petition agreed on by more than 20,000 people within 30 days, the relevant ministry or the President's office must provide answers or feedback. This study wants to figure out how this National Petition is different from previous platforms like Agora or E-Petitions and why it is so well-received by people. This study uses a mix of both qualitative and quantitative methods. First, we conducted a focus group interview to factorize experiences of using the National Petition into measurable constructs. Second, we did a survey o 156 Koreans who had experienced the National Petition. Results show that symbolism, usefulness, gratification, and trust have positive impact on continuous usage intention. This study argues that symbolism, usefulness, gratification, and trust factors should be in place rather than technical aspects in order to increase the actual participation of users on the online platform of deliberative democracy. In addition, this study is meaningful in that it examined how different the CheongWaDae's National Petition is from the existing platforms for collecting public opinions and analyzed factors that encourage continuous use.

• Journal of Distribution Science
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• v.14 no.9
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• pp.85-94
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• 2016

Purpose - Recently, Mobile technologies and devices including smart phones and tablets have increased the possibility of communicating with other people and sharing personal information without time and space restriction. In order to realize the market potential related to mobile technologies, a large number of internet services have been incorporated into mobile platforms. Especially, The number of MIM(Mobile Instant Messenger) users has been increasing dramatically and services using MIM platform also have diversified. In spite of drastic growth in markets related to MIM, there is little empirical research on MIM and users' behaviors. This study designed to examine the structural relationships among belongingness, loneliness, self-disclosure intention, system quality, and self-disclosure behavior in context of MIM. Research design, data, and methodology - Three hypotheses were about the relationship among belongingness, loneliness and self-disclosure intention. The other two hypotheses were about the moderating effect of system quality in the causal relationship between self-disclosure intention and self-disclosure behavior. The data was analyzed by structural equation modeling. Research data were obtained from 330 undergraduate students who were KakaoTalk users and total 314 valid questionnaires were used in the final analysis. Results - The results from this study are as follow. First, the belongingness and the loneliness had a significant impact on self-disclosure intention in MIM. Second, the self-disclosure intention in MIM also had a positive impact on the self-disclosure behavior. Lastly, there is a moderating effect of the system quality in the relationship between the self-disclosure intention and self-disclosure behavior in MIM. Specifically, the higher system quality level was perceived, the positive effect of the self-disclosure intention in MIM on the self-disclosure behavior was greater. Conclusions - Based on the results from this study, academic and practical implications can be drawn. First, the study extends the scope of research about SNS through focusing on MIM to be classified by closed type SNS and identifies the relationship between emotion, behavioral intention and behaviors in MIM. Second, this study provides strategic guidelines to increase the efficiency for promotion activity. Limitations for the study also should be discussed.

• Journal of the Ergonomics Society of Korea
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• v.33 no.6
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• pp.487-497
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• 2014

Objective: This study aims to develop and evaluate a multi-purpose rollator, which may be used as a seat, as a traditional walker, or as a storage basket for elderly farmers. Background: The rollators on the market are not user-friendly designed and seen inconvenient for elderly farmers to use, although they are sold at considerably high price. Since they lack enough space to load stuffs and are not durable or stable enough, they do not seem to be suitable for elderly farmers to use in rural areas. Method: Two types of methods were used in this study. First, the survey consisted of 19 questions was conducted among elderly farmers in rural areas, after using the developed rollator, to evaluate the usability of the rollator developed in this study. Second, EMG experiment was conducted to compare the existing rollator and developed rollator quantitatively. Through this experiment, we tried to verify the differences of muscle responses, when using the traditional and the developed ones, which have their own brake system, in the ramp. Results: The developed rollator was highly evaluated in most of the questions in the usability survey, except for the 'Weight' category in which the opinions were divided into three different types (Worse: 31%, Similar: 30%, Better: 36%). The result of EMG experiment showed that the existing rollator (7.4%MVC) demands more muscle strength than the developed rollator (5.5%MVC) does. By statistically analyzing the results of upper limb and lower limb respectively, we found out that all the muscles except deltoid in upper limb showed statistically significant differences in muscle activity when using the existing and the developed rollator. However, there was no statistical difference in lower limb muscles. Conclusion: The developed rollator in this study has maximized the functionality of the brake system, the storage and the chair, which were pointed out as the weaknesses of existing rollators. Furthermore, the developed rollator is designed to be more user-friendly, safe, durable, and effective for elderly farmers to use in rural areas, where roads are rough and bumpy. Application: We expect that the emergency brake system developed in this study would be utilized for other convenience equipment, such as strollers and carts, and that it would be able to develop and produce more secure and reliable equipment in the future.

• Spatial Information Research
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• v.22 no.5
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• pp.43-52
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• 2014

Recently, Big Data is a buzzword in the creative economy generation. The organizations related to spatial information society focus on building the spatial big data systems. As spatial big data is a combination of spatial information and big data, the data visualization is essential in order to utilize them efficiently. One of the great methodologies for data visualization is infographics. Nationally, Chousn.com initiated the infographics news in 2010. Korean Administration Branches also recognized the importance of infographic and they adopted infographics for their briefings from 2013. Internationally, Visual.ly is leading company in the infographics market and they produced noticeable interactive infographics for Egypt Parliamentary Elections results. In the defense part, Guardian's datajournalism of Afghanistan war log was a good example of utilizing infographics. Throughout the research, five requirements are extracted. First source data should have precision and accuracy in terms of time and space manner. Second, infographics images have a compressibility. Third, the infographics is properly processed for military commanders. Fourth, sharing, openness and communication are essential for high quality infographic. Lastly, infographics should be an analytic tool for predicting future event based on the past data. Infographics is not a direct representation of data but an analytic tool for helping user's choice and decision in critical moments.