• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.12A
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• pp.964-974
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• 2003

With increasing use of a personal mobile computer. the Mobile IPv6 is one of the main protocols that support mobility and complies with IPv6 specification. Similar to the mobile IPv6, the mobile IPv6 also has limitations on fast moving condition. The Hierarchical Mobile IPv6 is a solution that overcomes these limitations. The Hierarchical Mobile IPv6 is a micro mobility protocol that supports fast mobile IP handover and reduces signaling overhead with Mobility Anchor Point(MAP). But until now no paging method is applied to the Hierarchical Mobile IPv6 to reduce unnecessary signaling overhead and power consumption of mobile nodes. So, the paging mechanism for the Hierarchical Mobile IPv6 is proposed in this paper. the mechanism is implemented by making use of the destination option header and extension function and the last location algorithm. The results show that the Hierarchical Mobile IPv6 with the paging ability reduces the traffic of mobile networks by removing unnecessary binding update packet generated whenever handover takes place. Also, the larger the paging size is. the less the number of BU(Binding Update) massage generated.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.5
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• pp.95-103
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• 2008

The Network Mobility (NEMO) basic support protocol extends the operation of Mobile IPv6 to provide uninterrupted Internet connectivity to the communicating nodes of mobile networks. The protocol is not efficient to offer delays in data delivery and higher overheads in the case of nested mobile networks because it uses fairly sub-optimal routing and multiple encapsulation of data packets. In this paper, our scheme combining Hierarchical Mobile IPv6 (HMIPv6) functionality and Hierarchical Prefix Delegation (HPD) protocol for IPv6, which provide more effective route optimization and reduce packet header overhead and the burden of location registration for handoff. The scheme also uses hierarchical mobile network prefix (HMNP) assignment and tree-based routing mechanism to allocate the location address of mobile network nodes (MNNs) and support micro-mobility and intra-domain data communication. The performance is evaluated using NS-2.

• Journal of the Korea Society of Computer and Information
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• v.11 no.5 s.43
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• pp.165-173
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• 2006

Network Mobility Basic Support protocol enables mobile network to change their point of attachment to the Internet, but causes some problems such as suboptimal muting and multiple encapsulations. The proposed scheme, combining Prefix Delegation protocol with HMIPv6 concept can provide more effective route optimization and reduce the amount of packet losses and the burden of location registration for handoff. It also uses hierarchical mobile network prefix (HMNP) assignment and provides tree-based routing mechanism to allocate the location address of mobile network nodes (MNNs) and support micro-mobility. In this scheme, Mobility Management Router (MMR) not only maintains the binding informations for all MNNs in nested mobile networks, but also supports binding procedures to reduce the volume of handoff signals oyer the mobile network. The performance is evaluated using NS-2.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.3
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• pp.318-325
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• 2010

In this study, the wrapper database description language and model is suggested to collect product reviews from Korean shopping malls with multi-layer structures and are built in a variety of web languages. Above all, the wrapper based web crawlers have the website structure information to bring the exact desired data. The previously suggested wrapper based web crawler can collect HTML documents and the hierarchical structure of the target documents were only 2-3 layers. However, the Korean shopping malls in the study consist of not only HTML documents but also of various web language (JavaScript, Flash, and AJAX), and have a 5-layer hierarchical structure. A web crawler should have information about the review pages in order to visit the pages without visiting any non-review pages. The proposed wrapper contains the location information of review pages. We also propose a language grammar used in describing the location information.

• International Area Studies Review
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• v.21 no.4
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• pp.173-194
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• 2017

The research study conducted logistics regression analysis through HLM (Hierarchical Linear Modeling) and presented the value of the outcome in order to investigate characteristic factors of demanders which influence the intention to move into public rental housing. (1) The results of the regression analysis of characteristic factors of household and housing were analyzed as having the significant effect on the intention to move in public rental housing, according to residents moving in monthly rent housing, residents' occupations, rental housing, the number of household, the location of surrounding public rental housing, monthly average income, children's educational level, the number of children, the types of housing and one's own house, in order, out of the types of housing tenure. (2) The results of the regression analysis of characteristic factors of the conditions of location were analyzed that out of the conditions of location of the top five areas in public rental rates, what influences significant effects on the intention to move in public rental housing is the location of surrounding rental housing, income, the number of household and children, children's educational level, job state, housing types, ones' own house, rent housing, monthly rent housing, in order. (3) In case of Seoul, Expanding public rental housing is inevitable in order to stabilize ordinary people's housing stability, owing to the high and rental prices of private housing. Nevertheless, an accurate analysis of the intention to move in public rental housing has not been conducted. Eventually, the research was, thus, conducted, based on the fact that the preference on public housing is low. According to the analytic results of the study, it is required for the government institutions and agencies should consider individual and local characteristics and provide an alternative that meets the real situation, in order to help ordinary citizens with low incomes stabilize housing.

• Journal of KIISE:Databases
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• v.33 no.3
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• pp.299-309
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• 2006

Due to the rapid development in mobile communication technologies, the usage of mobile devices such as cell phone or PDA becomes increasingly popular. As different devices require different applications, various new services are being developed to satisfy the needs. One of the popular services under heavy demand is the Location-based Service (LBS) that exploits the spatial information of moving objects per temporal changes. In order to support LBS efficiently, it is necessary to be able to index and query well a large amount of spatio-temporal information of moving objects. Therefore, in this paper, we investigate how such location information of moving objects can be efficiently stored and indexed. In particular, we propose a novel location encoding method based on hierarchical administrative district information. Our proposal is different from conventional approaches where moving objects are often expressed as geometric points in two dimensional space, (x,y). Instead, in ours, moving objects are encoded as one dimensional points by both administrative district as well as road information. Our method is especially useful for monitoring traffic situation or tracing location of moving objects through approximate spatial queries.

• International Journal of Advanced Culture Technology
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• v.6 no.2
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• pp.72-79
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• 2018

The purpose of this study was to analyze general characteristics and empathy factors of nursing student's major satisfaction. Participants in this study were 235 students from both located in J do and C do Universities. The research method was a cross-sectional survey and the survey period was from September 1 to 10, 2017. The questionnaire was used to investigate general characteristics, empathy, and major satisfaction. The analysis was based on frequency analysis, p value of t or F value, Pearson correlation, regression analysis, and hierarchical regression analysis using SPSS 18.0. The result of this study were as follows: (1) The C University showed higher satisfaction than J University(3.44), (2) the factors affecting major satisfaction were school location, grade, religion, cognitive empathy, and emotional empathy correlated, Regression analysis was used to examine factors that correlated with major satisfaction, followed by hierarchical regression analysis to identify the most influential factors. (3) The result of the analysis showed that the greatest influence factors on major satisfaction were the University location(${\beta}=.325$, p<.01), the cognitive empathy (${\beta}=.287$, p<.01), and the next order was negative grade(${\beta}=-.230$, p<.01). Based on the results of this stud, the following conclusions can be drawn. The most influential factor in the major satisfaction was the school location, but this was an irreversible factor. Therefore, if the cognitive empathy factor and grades are corrected, it can be said that it can increase the satisfaction of major in nursing University students. In this study, it was emphasized that cognitive empathy contained in the course of nursing education program and suggested guidance on major satisfaction in lower grades.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.735-744
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• 2016

This study attempted quantitative analysis by space syntax on the plan of a non-hierarchical arrangement, which selected SANAA's work after Almere Stadt Theater, and analyzed the difference in the quantitative value of the non-hierarchical arrangement in plan that appears externally. The analysis results were as follows. First, SANAA's spaces with a non-hierarchical arrangement plan that appears externally showed a definite quantitative value difference, and had a hierarchical space difference in the plan that does not appear externally. Second, the spaces with a high integration value also had a high connectivity value, which is indicated by increasing the number of space openings using the method of giving hierarchy to the non-hierarchical arrangement plan or adjusting the size of the room or location to grant hidden hierarchy. Third, SANAA used exterior corridor rather than interior corridor in grid-type plan to solve the accessibility problem, and the open coat spaces between rooms provide natural lighting and ventilation and are used as equipment that controls the hidden hierarchy of space at the same time.

• Journal of Internet Computing and Services
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• v.8 no.6
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• pp.21-28
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• 2007

Hierarchical Mobile IPv6 improves performance of Mobile IPv6 by managing Binding Update in terms of location, With improved handover delay, realization of delay-sensitive services (e,g, VoIP or video streaming) has become more persuadable, Comparing with Mobile IPv6, however, Hierarchical Mobile IPv6 brings security threats related to Local Binding Update to mobile network, In the RFC 4140, specific methods to authenticate Local Binding Update message are not explicitly presented. It is essential that design secure architecture to address problems related to authenticating Local Binding Update, Many secure suggestions for Local Binding Update, however, concentrate on infrastructure-based solutions such as AAA PKI. These approaches may cause scalability problem when the suggested solutions are applied to real network. Therefore we suggest authentication method that doesn't require infrastructure, In addition to authentication of Local Binding Update, our method also provides mobile node with power saving ability.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.198-204
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• 2018

Background: The effective use of habitats is essential for the successful adaptation of a species to the local environment. Although habitats exhibit a hierarchical structure, including macro-, meso-, and microhabitats, the relationships among habitats of differing hierarchy have not been well studied. In this study, we studied the quantitative measures of microhabitat use of Gekko japonicus from three field populations in Japan: one at Tsushima Island, one at Nishi Park, Fukuoka, and one at Ohori Park, Fukuoka. We investigated whether land cover type, a higher hierarchical habitat component, was associated with quantitative microhabitat use, a lower hierarchical component, in these populations. Results: The substrate temperature where we located geckos (SubT) and the distance from the ground to the gecko (Height) were significantly different among the three populations. In particular, SubT on Tsushima Island was lower than it was in the other two populations. Irradiance at gecko location and Height were significantly different among the land cover types. In particular, Height in evergreen needleleaf forest was significantly lower than that in deciduous broadleaf forest. Furthermore, significant interactions between population and land cover type were observed for the SubT and Height variables. Conclusions: The quantitative measures of microhabitat use of G. japonicus varied with population and land cover type, which exhibited significant interaction effects on microhabitat use variables. These results suggest that higher hierarchical habitat components can affect the quantitative measures of lower hierarchical microhabitat use in nocturnal geckos.