• Proceedings of the Korea Database Society Conference
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• 1999.06a
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• pp.175-186
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• 1999

Detecting the features of significant patterns from their own historical data is so much crucial to good performance specially in time-series forecasting. Recently, a new data filtering method (or multi-scale decomposition) such as wavelet analysis is considered more useful for handling the time-series that contain strong quasi-cyclical components than other methods. The reason is that wavelet analysis theoretically makes much better local information according to different time intervals from the filtered data. Wavelets can process information effectively at different scales. This implies inherent support fer multiresolution analysis, which correlates with time series that exhibit self-similar behavior across different time scales. The specific local properties of wavelets can for example be particularly useful to describe signals with sharp spiky, discontinuous or fractal structure in financial markets based on chaos theory and also allows the removal of noise-dependent high frequencies, while conserving the signal bearing high frequency terms of the signal. To date, the existing studies related to wavelet analysis are increasingly being applied to many different fields. In this study, we focus on several wavelet thresholding criteria or techniques to support multi-signal decomposition methods for financial time series forecasting and apply to forecast Korean Won / U.S. Dollar currency market as a case study. One of the most important problems that has to be solved with the application of the filtering is the correct choice of the filter types and the filter parameters. If the threshold is too small or too large then the wavelet shrinkage estimator will tend to overfit or underfit the data. It is often selected arbitrarily or by adopting a certain theoretical or statistical criteria. Recently, new and versatile techniques have been introduced related to that problem. Our study is to analyze thresholding or filtering methods based on wavelet analysis that use multi-signal decomposition algorithms within the neural network architectures specially in complex financial markets. Secondly, through the comparison with different filtering techniques' results we introduce the present different filtering criteria of wavelet analysis to support the neural network learning optimization and analyze the critical issues related to the optimal filter design problems in wavelet analysis. That is, those issues include finding the optimal filter parameter to extract significant input features for the forecasting model. Finally, from existing theory or experimental viewpoint concerning the criteria of wavelets thresholding parameters we propose the design of the optimal wavelet for representing a given signal useful in forecasting models, specially a well known neural network models.

• Journal of the Korean Geographical Society
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• v.40 no.5 s.110
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• pp.473-490
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• 2005

The term hybridity has recently emerged as one of the most popularized leitmotivs in contemporary diasporic and transnational problematics on migrants' nomadic experiences. Especially, in postcolonial politics, hybridity is argued to provide a critical 'third space' on which to challenge discursive boundaries and redescribe power-embedded history However, this paper suggests that the hybrid subject position can be easily articulated in producing new cultural discourse and empowering hegemonic subjects in certain spates. Based on distinguishing the intentional, conscious hybridity from the organic, lived hybridity, this research Intends to investigate the Janus-faced, double-edged nature of the postcolonial politics of hybridity in the case of Los Angeles Koreatown. First, I discuss how a place of organic hybridity in Koreatown can lead to challenging invented and depoliticized ethnicity. At the second half of this paper, 1 focus on understanding the ways in which new Korean American professionals and elites employ the discourse of '1.5 generation' as an intentional hybridity for empowering their own political position at a local scale. I conclusively suggest that hybridity should be a deconstructive strategy to unlearn dominant socio-spatial boundaries rather than bring about the third space as a reterritorialized political position.

• Journal of the Korean earth science society
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• v.36 no.3
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• pp.280-299
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• 2015

The purpose of this study was to investigate the effects of an instruction using geologic planar figures on high school students' ability of spatial visualization and geologic spatial ability and also to explore its applicability as an instructional strategy through the investigation of students' perception about the instruction using mixed methodology. For this purpose, we developed 10 planar figures of geologic structures (2 horizontal layers, 2 vertical layers, 4 angular layers, 1 fault, and 1 fold), and tested students' spatial visualization ability and geologic spatial ability before and after the implementation in class. In addition, in order to investigate students' perception on the instruction, we conducted quantitative research using questionnaires comprised of the cognitive and the affective domain, and followed by focus group interview that was conducted to obtain deeper understanding of their perception. Findings revealed that the instruction using geologic planar figures was effective to enhance spatial visualization ability and geologic spatial ability. It was also helpful for students to enhance their ability to perceive the spatial configuration of the geologic structures as well as the ability to penetrate visually into the images of the structures. The results of the students' perception on the instruction showed that the students recognized the instruction using geologic planar figures as a strongly positive teaching method both in the cognitive and affective domain. We concluded that geologic planar figures could be used as an effective tool for the lesson of 'mapping and interpreting of geological map', and be highly applicable for the advanced class in high schools.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.577-586
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• 2014

As SNS has increased its influence on the society as a whole, companies also have started to consider how to take advantage of the new service paying specific attention to its characteristics of immediacy, sharability and interactivity. This study aims to circumstantiate the relationship between a task support tool of SNS and task-media fit, user characteristics and performance by focusing on its usage in work field. To address this issue, a Task-Technology Fit model is used to propose a research model considering the characteristics of SNS as a social element, information technology as well as its user characteristics. The outcome shows that job characteristics, virtual competence and media characteristics have a significant influence on task-media fit, whereas virtual competence and SNS characteristics variables have a significant influence on SNS usage. Besides, task-media fit has a significant influence on SNS usage and work performance while SNS usage has a significant influence on work performance. The study suggests that strategic use of SNS helps improve work performance and these individual characteristics should be considered in planning of SNS utilizing strategy.

• Journal of Korean Society of Forest Science
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• v.109 no.2
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• pp.223-230
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• 2020

Central Asia has great growth potential for cooperation as the Korean Official Development Assistance (ODA) program expands and diversifies. In the case of the forest sector, Korea's successful greening experience has attracted interest from countries in Central Asia. In particular, the depletion of the Aral Sea and a widespread environmental degradation should motivate regional cooperation as well as highlights the need to establish a multilateral cooperative system. The limitation of existing bilateral cooperation, which is the limitation of South-South cooperation, is underscored by the engagement of new donors or the multilateral cooperation and triangular cooperation of organizations is receiving new attention. In addition, Central Asia is suitable for implementing the basic concepts of triangular cooperation. Korea is able to make complementary regional agreements using friendly partnerships with Kazakhstan (the Emerging Donor) and Uzbekistan (the second South Korean Focus Country of ODA). To reinterpret the basic concept of triangular cooperation, three regional cooperation strategies for Central Asia are proposed in this study: windbreak forest development to guarantee resident settlement, resident income increase, and protection of the Aral Sea from further degradation.

• Asia pacific journal of information systems
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• v.17 no.4
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• pp.1-29
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• 2007

The brand-based online community recently plays an important roles for consumers to facilitates searching and sharing information among them. Firms often find such a brand community as a critical channel to gain collective intelligence for developing new ideas and products. As a new web platform such as web 2.0 has been introduced, consumers could more easily participate in the new social networks created by sharing mutual value and belief among themselves. Accordingly firms began to recognize potentials of online brand assets and pay attention to the importance of online brand community loyalty. Previous research related to online community tends to focus on identifying the antecedents of community loyalty and their subsequent impacts on brand. They, however, tend to neglect the importance of individual characteristics of online community users. As integrating the fragmented variables with an individual characteristics, therefore, this study reexamined the impacts of interactivity, information, reward, and personalization services provided by an online brand community on the sense of community, community loyalty, and brand attitude. Also, this study investigated how users' individual characteristics(need for cognition: NFC) can play moderating roles among the variables identified in the previous research. A field survey was administrated and 671 valid samples were collected. In order to test the hypothesis we conducted the multi-sample structural equation modeling(MSEM) between two groups(a group with high vs. a group with low level of NFC). Results show that previously identified variables such as interactivity, information, reward, and personalization services have significant effects on the sense of community as previous research demonstrated. Subsequently, the sense of community positively influences the community loyalty and brand attitude. However, when considering the NFC as a moderating variable, we found that the effect of interactivity and reward service on the sense of community was stronger for a group with a lower level of NFC compared to a group with a higher level, while the effect of information providing service on the sense of community was stronger for a group with a higher level of NFC compared to a group with a lower level. This research revealed that NFC can affect the degree of individual perception on the sense of community which has been considered as an important indicator for the community loyalty and brand attitude. Hence, when firms developing customer relation strategy through building an online brand community, they need to reflect customers' NFC and accordingly provide varying degree of interactivity, information, reward, and personalization services.

• Journal of Korea Port Economic Association
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• v.24 no.2
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• pp.43-69
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• 2008

The labor contract Law has been prepared as an important solution for social stability. After long disputes around the orientations of the law, On June 29, 2007, the new Chinese labor contract law is passed. This law reflects the changing labor relations because of economic reforms like restructuring of the state-owned enterprises and so on. This law contains more market-oriented clauses that are supplemented by corporatist scheme supported by trade unions than the first draft. This law emphasize labor's rights and interests to remove prior labor contract problem. So Chines government see this law as standard law to restructure social relationship and also require firms to corporate social responsibility. Therefore, implementation of the new Chinese labor contract law bring about increasing labor cost, infringement of autonomy for human resource management, rigidity of industrial relations. Under these situation, Korean shipping and port logistics companies need to introduce management system of minimized employment, prepare human resource management in response to long-term employment, maintain favor relationship with trade union, and set up counteiplan about risk of a labor dispute.

• The KIPS Transactions:PartD
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• v.8D no.4
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• pp.313-326
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• 2001

The XML that was proposed as a next-generation standard for describing Web documents is widely used in various Web-based applications. In addition, XML documents on the Web link each other by hyperlinks. The current works on XML focus on the XML storage system that can efficiently store, manage, and retrieve XML documents. However, the research on the query language that supports the XML links and on the XML retrieval systems to process the XML links, is little conducted until now. In this paper, we propose an extension of an XML query language for expressing the XML link query and its processing scheme. A link query is to retrieve contents from an XML document (a query document) and from the XML documents (referenced documents) that are referred to by the links in the query document. As far as retrieving from the referenced documents is concerned, the current practice is to manually generate queries to get the partial results, and to repeat such a procedure. The purpose of link query processing in this paper is to eliminate the manual work altogether in getting the complete query result. The performance analysis shows that our link query processing strategy outperforms the conventional approach including the manual tasks. The more links to the referenced documents and the more referenced documents there are in the site storing the query document, the more query processing time decreases.

• Atmosphere
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• v.15 no.4
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• pp.213-227
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• 2005

The global mean surface temperature has already increased by $0.6{\pm}0.2^{\circ}C$ over the last century, and warming in Korea is approximately twice as large as the global average. The Intergovernmental Panel on Climate Change (IPCC) has concluded that the majority of warming over the past 50 years could be attributed to human activities (IPCC, 2001a). In addition, the global surface temperature is expected to increase by 1.4 to $5.8^{\circ}C$ depending on the greenhouse gas emission scenarios during the $21^{st}$ century.Climate change resulting from increased greenhouse gas concentrations has the potential to harm societies and ecosystems. Reductions in emissions of greenhouse gases and their concentration in the atmosphere will reduce the degree and likelihood of significant adverse conditions due to the anticipated climate change. Mitigation policy has generally been the primary focus of public attention and policy efforts on climate change. However, some degree of climate change is inevitable due to the combination of continued increases in emissions and the inertia of the global climate system. Adaptation actions and strategies are needed for a complementary approach to mitigation. The United Nations Framework Convention on Climate Change (UNFCCC) currently addresses vulnerability and adaptation in the context of climate change negotiations and in future adaptation may be an important element of work under the Kyoto Protocol. There are several on-going programs to develop effective adaptation strategies and their implementation. But in general, many other countries are still on an initiating stage. The climate change science programs of the United States, Japan, England, and Germany are initiated to understand the current status of climate change science and adaptation researches in the developed countries. In this study, we propose the improvement on systems in policy and research aspects to effectively perform the necessary functions for development of nation-wide adaptation measures and their implementation. In policy aspect, the Korean Panel on Climate Change (KPCC) is introduced as a coordinating mechanism between government organizations related with climate change science, impact assessment and adaptation. Also in research aspect, there is a strong consensus on the need for construction of a national network on climate change research as trans-disciplinary research network.

• Information Systems Review
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• v.10 no.2
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• pp.1-19
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• 2008

The purpose of this research is to schematize and suggest the new trends of study and changing aspects of science and technology hidden in a bibliographical phenomenon of documentation to researchers and policy-makers all through the Knowledge Map. The field of study to be analyzed in this research is the Access Network field. The reason why this field has been selected as the main target of study is that the Access Network field is economically important and characterized by its wide sphere where a variety of fields are interconnected. In addition, it is important to measure the applied as well as fundamental aspects of technology by using bibliographical method and technique. Knowledge Map successfully visualizes the inter-relations of the keywords and sub-fields of Access Network. The importance of visualizing methods in the convincing presentation of results has not been sufficiently understood in the past. Knowledge Map opens a new opportunity for cartography of science and information visualization. The Knowledge Map results have produced a great deal more than statistical artifact. We aimed to exploit the visualization effect of the Knowledge Maps to the aid of searchers in Access Network domain, and the results are quite encourging.