• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.871-874
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• 2010

Needs for Smart Grid development are increasing all over the world as a solution to its problem according to depletion of energy resources, climatic and environmental rapidly change and growing demand for electrical power. Especially decentralized power is attracting world's attention. In this mood a new era for a unit scale of decentralized power environment is on its way in building. However there is a problem to have to be solved in the uniformity of power quality because the amount of power generated from renewable energy resources such as wind power and solar light is very sensitive to climate fluctuation. And thus this paper tries to suggest an energy management method on basis of real time monitoring for meteorological data. In the current situation of lacking in USN-based killer application in Smart Grid field, this paper proposes the USN-based DER management system which collects the meteorological data and control power system througout utilizing wireless sensor network technique this business. This communication technique is regarded to be efficient in aspects of installation cost and tits maintenance cost. The proposed EMS model embodies the method for predicting the power generation by monitoring and analyzing the climatic data and controling the efficient power distribution between the renewable energy and the existing power. The ultimate goal of this paper is to provide the technological basis for achieving zero-energy house.

• Korean Security Journal
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• no.29
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• pp.301-336
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• 2011

This exploratory study aims to review the risks and threats of social network services(SNSs), particularly focusing upon the policing perspective. This paper seeks to acknowledge the present risk/danger of SNSs and the very significance of establishing a strategic framework to effectively prevent and/or control criminal misuse of SNSs. This research thus advocates that proactive study on security issues and criminal aspects of SNSs and preventive countermeasures can play a significant role in policing the networked society in the time of digital/internet age. Social network sites have been increasingly attracting the attention of entrepreneurs, and academic researchers as well. In this exploratory article, the researcher tried to define concepts and features of SNSs and describe a variety of issues and threats posed by SNSs. After summarizing existing security risks, the researcher also investigated both the potential threats to privacy associated with SNSs, such as ID theft and fraud, and the very danger of SNSs in case of being utilized by terrorists and/or criminals, including cyber-criminals. In this study, the researcher primarily used literature reviews and empirical methods. The researcher thus conducted extensive case studies and literature reviews on SNSs. The literature reviews herein cover theoretical discussions on characteristics, usefulness, and/or potential danger/harm of SNSs. Through the literature review, the researcher also concentrated upon being able to identify a strategic framework for law enforcement to effectively prevent criminal misuse of SNSs The limitation of this study can be lack of statistical data and attempts to examine previously un-researched area in the field of SNS and its security risks and potential criminal misuse. Thus, to supplement this exploratory study, more objective theoretical models and/or statistical approaches would be needed to provide law enforcement with sustainable policing framework and contribute to suggesting policy implications.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.35-40
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• 2019

It is important to constantly provide service in real-time multimedia applications using multicast. Transmission path reconstruction occurs in hybrid multicast using Internet Protocol (IP) multicast and ALM in order to adapt the network status to things like congestion. So, there is a problem in which real-time QoS is reduced, caused by an increase in end-to-end delay. In this paper, we want to solve this problem through multi-layer transmission path construction. In the proposed method, we deploy the control server and application layer overlay host (ALOH) in each multicast domain (MD) for hybrid multicast construction. After the control server receives the control information from an ALOH that joins the MD, it makes a group based on the hop count and sends it to the ALOH in each MD. The ALOH in the MD performs the role of sending the packet to another ALOH and constructs the multi-layered transmission path in order of priority by using control information that is received from the control server and based on the delay between neighboring ALOHs. When congestion occurs in, or is absent from, the ALOH in the upper MD, the ALOH selects the path with the highest priority in order to reduce end-to-end delay. Simulation results show that the proposed method could reduce the end-to-end delay to less than 289 ms, on average, under congestion status.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.3
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• pp.27-46
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• 2022

Today, public libraries are contributing deeply to our society by strengthening their ability and services to identify and respond to users' needs through various programs. However, it is difficult to find a study that analyzed the research status of public library programs or changes over time. Therefore, for the purpose of systematically grasping research trends in the field of overseas public library programs, an intellectual structure analysis based on keyword profiling was performed. Specifically, subject terms analysis, network analysis and cluster analysis, and analysis by period/year were performed based on the controlled keywords (subject terms) of journal articles papers searched in the LISTA database. As a result, first, it was found that 9 subjects corresponding to all global/hot/local topics are leading the research in the field of overseas public library programs. Second, five research areas in the field of overseas public library programs(cultural programs, outreach programs, activity programs, public services, community) could be visualized and clearly identified. Third, research in the field of overseas public library programs began in earnest in the late 1990s and was active from the mid-2000s to the early 2010s, and after that, it was found to be somewhat stagnant until recently. This study is the result of specifically identifying research trends on programs that recently emerged as a major task of public libraries, and can be used as basic data and prior knowledge to explore the development direction of public library programs in the future.

• Information Systems Review
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• v.22 no.2
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• pp.25-41
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• 2020

Along with the expectation about 5G network commercialization, interests in realistic and immersive media industries such as virtual reality (VR) are increasing. However, most of studies on VR still focus on video technologies instead of factors for popularity and consumption. Thus, the main objective of this research is to identify meaningful factors, which affect the view counts of VR videos and to provide business implications of the content strategies for VR video creators and service providers. Using a regression analysis with 700 VR videos, this study tries to find major factors that affect the view counts of VR videos. As a result, user assessment factors such as number of likes and sicknesses have a strong influence on the view counts. In addition, the result shows that both general information factors (video length and age) and content characteristic factors (series, one source multi use (OSMU), and category) are all influential factors. The findings suggest that it is necessary to support recommendation and curation based on user assessments for increasing popularity and diffusion of VR video streaming.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.1
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• pp.59-70
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• 2024

As urbanization progresses, the demand for parks and green space is increasing. Park green spaces in the city are important spaces in the city because they are recognized as spaces where people can freely engage in outdoor activities. The park service area is a measure that shows the extent to which services are provided based on distance. In this process, the concept of accessibility plays an important role, and walking, in particular, as the most basic means of transportation for people and has a great influence on the use of parks. However, the current park service area analysis focuses on discovering underprivileged areas, so detailed evaluation of beneficiary areas is insufficient. This study seeks to evaluate park service areas based on the pedestrian accessibility and the pedestrian network. Park services are services that occur when users directly visit the park, and accessibility is expected to be reflected in terms of usability. To quantify the pedestrian network, this study used space syntax to analyze pedestrian accessibility based on integration values. The integration values are an indicators that quantify the level of accessibility of the pedestrian network, and in this study, the higher the integration value, the higher the possibility of park use. The results of the study are as follows. First, Bundang-gu's park service area accounts for 43%, and includes most sections with high pedestrian accessibility, but some sections with good pedestrian accessibility are excluded. This can be seen as a phenomenon that occurs when residential areas and commercial and business areas are given priority during the urban planning process, and then park and green areas are selected. Second, based on Bundang-gu, the park service area and pedestrian accessibility within the park service area were classified by neighborhood unit. Differences appear for each individual neighborhood unit, and it is expected that the availability of the park will vary accordingly. In addition, even in areas created during the same urban planning process, there were differences in the evaluation of park service areas according to pedestrian accessibility. Using this, it is possible to evaluate individual neighborhood units that can be reflected in living area plans, and it can be used as a useful indicator in park and green space policies that reflect this in the future.

• Journal of the Society of Disaster Information
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• v.11 no.4
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• pp.556-569
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• 2015

With about 75% of the population of Korea criticizing the government's disaster policy and a failure to respond to large-scale emergency like the Sewol ferry sinking means that there is a deep distrust in the government. In order to prevent dreadful disasters such as the Sewol ferry sinking, it is important to secure a prime time with respect to disaster safety. Improving crisis management skills and managerial role of police officers who are in close proximity to the people is necessary for the success of disaster management. With disaster management as one of the most essential missions of the police, as a part of a national crisis management, a step by step strengthening of the disaster safety management system of the police is necessary, as below. First, at the prevention phase, law enforcement officers were not injected into for profit large-scale assemblies or events, but in the future the involvement, injection should be based on the level of potential risk, rather than profitability. In the past and now, the priortiy was the priority was on traffic flow, traffic communication, however, the paradigm of traffic policy should be changed to a safety-centered policy. To prevent large-scale accidents, police investigators should root out improper routines and illegal construction subcontracting. The police (intelligence) should strengthen efforts to collect intelligence under the subject of "safety". Second, with respect to the preparatory phase, on a survey of police officers, the result showed that 72% of police officers responded that safety management was not related to the job descriptions of the police. This, along with other results, shows that the awareness of disaster safety must be adopted by, or rather changed in the police urgently. The training in disaster safety education should be strengthened. A network of experts (private, administrative, and police) in safety management should be established to take advantage of private resources with regard to crisis situtions. Third, with respect to the response phase, for rapid first responses to occur, a unified communication network should be established, and a real-time video information network should be adopted by the police and installed in the police situation room. Fourth, during the recovery phase, recovery teams should be injected, added and operated to minimize secondary damage.

• Journal of Korean Society for Geospatial Information Science
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• v.8 no.1 s.15
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• pp.51-63
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• 2000

Dynamic traffic assignment(DTA) has been a topic of substantial research during the past decade. While DTA is gradually maturing, many aspects of DTA still need improvement, especially regarding its formulation and solution algerian Recently, with its promise for In(Intelligent Transportation System) and GIS(Geographic Information System) applications, DTA have received increasing attention. This potential also implies higher requirement for DTA modeling, especially regarding its solution efficiency for real-time implementation. But DTA have many mathematical difficulties in searching process due to the complexity of spatial and temporal variables. Although many solution algorithms have been studied, conventional methods cannot iud the solution in case that objective function or constraints is not convex. In this paper, the genetic algorithm to find the solution of DTA is applied and the Merchant-Nemhauser model is used as DTA model because it has a nonconvex constraint set. To handle the nonconvex constraint set the GENOCOP III system which is a kind of the genetic algorithm is used in this study. Results for the sample network have been compared with the results of conventional method.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.4
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• pp.31-40
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• 2016

In vehicular ad-hoc networks (VANETs), vehicles sense information on emergency incidents (e.g., accidents, unexpected road conditions, etc.) and propagate this information to following vehicles and a server to share the information. However, this process of emergency message propagation is based on multiple broadcast messages and can lead to broadcast storms. To address this issue, in this work, we use a novel approach to detect the vehicles that are farthest away but within communication range of the transmitting vehicle. Specifically, we discuss a signal-to-noise ratio (SNR)-based linear back-off (SLB) scheme where vehicles implicitly detect their relative locations to the transmitter with respect to the SNR of the received packets. Once the relative locations are detected, nodes that are farther away will set a relatively shorter back-off to prioritize its forwarding process so that other vehicles can suppress their transmissions based on packet overhearing. We evaluate SLB using a realistic simulation environment which consists of a NS-3 VANET simulation environment, a software-based WiFi-IP gateway, and an ITS server operating on a separate machine. Comparisons with other broadcasting-based schemes indicate that SLB successfully propagates emergency messages with latencies and hop counts that is close to the experimental optimal while reducing the number of transmissions by as much as 1/20.

• The KIPS Transactions:PartB
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• v.12B no.6 s.102
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• pp.679-684
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• 2005

There are a few representative wireless network access technologies used widely. WWAN is celluar based telecommunication networks supporting high mobility, WLAN ensures high data rate within hotspot coverage, and WDMB support both data and broadcasting services correspondingly. However, these technologies include some limitations especially on the mobility, data rate, transmission direction, and so on. In order to overvome these limitations, there are various studies have been proposed in terms of 'Vortical Handoff' that offers seamless connectivity by switching active connection to the appropriate interface which installed in the mobile devices. In this paper, we propose the interface selection algorithm and network architecture to maximize the life time of entire system by minimizing the unnecessary energy consumption of another interfaces such as WLAN, WDMB that are taken in the user equipment. In addition, by using the results of analyzing multiple types of traffic and managing user buffer as a metric for vertical handoff, we show that the energy efficiency of our scheme is $75\%$ and $34\%$ than typical WLAN for WDMB and WLAN preferred schemes, correspondingly.