• Korea Multimedia Society
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• v.12 no.4
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• pp.28-40
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• 2008

Vehicular ad hoc networks (VANETs) are a practical application class of wireless ad hoc networks, which consist of moving vehicles equipped with radio communication capabilities that collaborate to form a temporary network. This paper addresses issues and protocols of multihop routing in such emerging networks in the context of safety and infotainment applications. Due to the highly dynamic mobility of vehicles, frequent link breakage and short connection time are inevitable and, thus, the routing is a challenging task and interest for many researchers and industrial community. The frequent and dynamic change of topology makes the topology-based routing unreliable but the position-based routing more effective. The position-based routing consists of the location service which maps a node id to a geo-graphical position and the forwarding scheme which selects the next hop based on geo-graphical information of the node, its neighbors and the destination. The routing techniques are further categorized into geographical forwarding, trajectory forwarding and opportunistic forwarding based on the forwarding scheme. In this paper, we first present the distinguished properties of VANETs and the challenges and intractable issues posed in designing the routing protocols, followed by the comprehensive survey of existing routing protocols. Then, the different routing protocols designed for VANETs are compared in terms of characteristics, performance and application domains.

• Environmental Engineering Research
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• v.21 no.2
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• pp.140-144
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• 2016

Owing to the kinetic differences in ammonia oxidation among ammonia-oxidizing microorganisms (AOM), there is no standard set of kinetic values that can be used as a representative set for nitrifying wastewater treatment plant (WWTP) design. As a result, this study clarified a link between the half-saturation constants for ammonia oxidation (Ks) and the dominant ammonia-oxidizing bacterial (AOB) groups in sludge from full-scale WWTPs and laboratory-scale nitrifying reactors. Quantitative polymerase chain reaction analyses revealed that AOB affiliated with the Nitrosomonas oligotropha cluster were the dominant AOM groups in the sludge taken from the low-ammonia-level WWTPs, while AOB associate with the Nitrosomonas europaea cluster comprised the majority of AOM groups in the sludge taken from the high-ammonia-level WWTPs and nitrifying reactors. A respirometric assay demonstrated that the ammonia Ks values for the high-ammonia-level WWTPs and nitrifying reactors were higher than those of the low-ammonia-level plants. Using the Ks values of available AOM cultures as a reference, the Ks values of the analyzed sludge were mainly influenced by the dominant AOB species. These findings implied that.different sets of kinetic values may be required for WWTPs with different dominant AOM species for more accurate WWTP design and operations.

• Korean Journal of Adult Nursing
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• v.17 no.3
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• pp.411-424
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• 2005

Purpose: The purpose of this study was to develop and evaluate e-EBPP(Evidence-based Practice Protocol) system for nursing care for patients with dementia to facilitate the best evidence-based decision in their dementia care settings. Method: The system was developed based on system development life cycle and software prototyping using the following 5 processes: Analysis, Planning, Developing, Program Operation, and Final Evaluation. Result: The system consisted of modules for evidence-based nursing and protocol, guide for developing protocol, tool for saving, revising, and deleting the protocol, interface tool among users, and tool for evaluating users' satisfaction of the system. On the main page, there were 7 menu bars that consisted of Introduction of site, EBN info, Dementia info, Evidence Based Practice Protocol, Protocol Bank, Community, and Site Link. In the operation of the system, HTML, JavaScript, and Flash were utilized and the content consisted of text content, interactive content, animation, and quiz. Conclusion: This system can support nurses' best and cost-effective clinical decision using sharable standardized protocols consisting of the best evidence in dementia care. In addition, it can be utilized as an e-learning program for nurses and nursing students to learn use of evidence based information.

• Journal of Technology Innovation
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• v.16 no.2
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• pp.17-40
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• 2008

The collaboration among academia, industry, and public research sector gains importance in these days. This is essential for implement competent regional and national innovation systems. There have been many governmental programs for activating collaboration among innovation actors. Most policy programs for collaboration have aimed at increasing S&T and innovation potential and constructing S&T infrastructure. However, Korea has not produced a sufficient level of collaboration, especially on regional level. Most policy programs could not reach regions and many regions have no enough innovation actors. In order to activate R&D collaboration, therefore, we suggest that Korean S&T community should build and implement "collaborative research centers" all over the regions. This concept is very new approach, especially because it focuses on collaboration among regional innovation actors. In this paper, we discuss a concept, type, and execution strategy of collaboration research centers. We expect that these centers will play an important role in implementing successful regional innovation systems, as they will link regional innovation actors very closely.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.5
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• pp.2144-2165
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• 2016

In a vehicular ad hoc network, the communication links are unsteady due to the rapidly changing topology, high mobility and traffic density in the urban environment. Most of the existing geographical routing protocols rely on the continuous transmission of beacon messages to update the neighbors' presence, leading to network congestion. Source-based approaches have been proven to be inefficient in the inherently unstable network. To this end, we propose an opportunistic beaconless packet forwarding approach based on a modified handshake mechanism for the urban vehicular environment. The protocol acts differently between intersections and at the intersection to find the next forwarder node toward the destination. The modified handshake mechanism contains link quality, forward progress and directional greedy metrics to determine the best relay node in the network. After designing the protocol, we compared its performance with existing routing protocols. The simulation results show the superior performance of the proposed protocol in terms of packet delay and data delivery ratio in realistic wireless channel conditions.

• The Korean Journal of Rehabilitation Nursing
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• v.19 no.2
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• pp.100-107
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• 2016

Purpose: The goal of this study was to examine the association between perceived racial discrimination and substance use and the potential moderating effect of perceived parental affection between the two variables. Methods: A total of 101 Korean American adolescents participated in this cross-sectional study utilized an online survey. Descriptive statistics were used to describe for means and frequencies and the patterns of substance use. Logistic regression analysis was also used to examine the association between perceived discrimination and substance use. Results: Ninety percent of the participants reported perceiving racial discrimination, and 21% had used at least one kind of substance in the month prior to taking the survey. The most frequently used substance was alcohol, followed by marijuana and tobacco products. Logistic regression analysis revealed a link between perceived racial discrimination and substance use (OR = 1.74, 95% CI = 1.01, 3.00). However, parental affection did not moderate between racial discrimination and substance use. Conclusion: These findings suggest that perceived racial discrimination is positively associated with substance use among Korean American adolescents, and health care providers, counselors, and school nurses should screen for discrimination-related stress and substance use in this population.

• Journal of the Korean Institute of Educational Facilities
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• v.18 no.3
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• pp.43-51
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• 2011

The purpose of this study is to analyze the characteristic of common space of public schools in New York City and how the common space can perform a decisive role in enriching public space not as simply connecting between programs but as common space for a wide range of uses for communities as well as students. This study illustrates with a general design guideline of SCA(School of Construction Authority) and how the rules help the common space as an interactive link between community and site/site and school building/building and outdoor space/outdoor space and lobby in the urban context. Since its founding in New York City, 1958, Mitchell/Giurgola Architects office has dedicated itself to working with institutions and public and private schools for 50 years and has been working with SCA for 10 public schools since 1990. Through five school examples by Mitchell Giurgola architects, the study describes how the office suggests public "place" interweaving inner public space and outer public space through lobbies. A result of this research can be proposed what improvements should be made on common space in domestic schools by analyzing of positive aspects of SCA schools.

• Journal of Information Technology Services
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• v.18 no.4
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• pp.97-113
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• 2019

With the development of sensor, communication and intelligent software technology, expectation of IoT-based service which can receive desired service automatically and anytime, anywhere is getting higher. In addition, IoT-based services have begun to anticipate the development of a hyper-connected society. Despite these expectations and anticipations, few studies have empirically identified ways to improve the intentions of prospective customers to use IoT-based services. Therefore, the purpose of this paper is to propose a theoretical model that can explain the factors that determine the intention of using IoT-based services. In addition, this study investigates what factors affect the intention to use IoT-based services focusing on the connectedness. Especially, perceived connectivity with the (virtual) community, unlike the connectivity with the machines, is newly proposed, to understand the IoT technology adoption behavior. The empirical results suggest that social relationship is one of the critical factors to affect the use of services running on interconnected technology such as IoT. When IoT-based service is recognized as a link to other communities, it has been found to have a positive effect on intention to use via perceived belongingness.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.12
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• pp.767-775
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• 2014

New material design has obtained tremendous attention in material science community as the performance of new materials, especially in nano length scale, could be greatly improved to applied in modern industry. In certain conditions limiting experimental synthesis of these new materials, new approach by computer simulation has been proposed to be applied, being able to save time and cost. Recent development of computer systems with high speed, large memory, and parallel algorithms enables to analyze individual atoms using first principle calculation to predict quantum phenomena. Beyond the quantum level calculations, mesoscopic scale and continuum limit can be addressed either individually or together as a multi-scale approach. In this article, we introduced current endeavors on material design using analytical theory and computer simulations in multi-length scales and on multi-physical properties. Some of the physical phenomena was shown to be interconnected via a cross-link rule called 'cross-property relation'. It is suggested that the computer simulation approach by multi-physics analysis can be efficiently applied to design new materials for multi-functional characteristics.

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.289-294
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• 2019

In order to prevent recidivism of ex-offenders, this paper needs to provide various ways of helping out-of-pocket-survivors adapt to the local community. One of solutions is the employment link through appropriate vocational training. A recent study from the US Department of Justice found that about 60% of ex-offenders unemployed for one year after their release. In such a situation, the employment possibility of ex-offenders with disabilities may even lower, so called "Dual Barriers". The purpose of this study is to present strategies to reduce the recidivism rate and increase the employment possibility of ex-offenders with disabilities presenting the cases in in the United States through literature reviews related.