• Journal of the Korea Society of Computer and Information
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• v.18 no.3
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• pp.47-57
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• 2013

Location privacy has been a serious concern for mobile users who use location-based services to acquire geographical location continuously. Spatial cloaking technique is a well-known privacy preserving method, which blurs an exact user location into a cloaked area to meet privacy requirements. However, cloaking for continuous moving object suffers from cloaked area size problem as it is unlikely for all objects travel in the same direction. In this paper, we propose a grid-based privacy preservation method with an improved Earth Mover's Distance(EMD) metric weight update scheme for semantic cloaking. We also define a representative cloaking area which protects continuous location privacy for moving users. Experimental implementation and evaluation exhibit that our proposed method renders good efficiency and scalability in cloaking processing time and area size control. We also show that our proposed method outperforms the existing method by successfully protects location privacy of continuous moving objects against various adversaries.

• Korean Journal of Remote Sensing
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• v.23 no.5
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• pp.465-471
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• 2007

Many hospitals have been considering new technology such as wireless sensor network(WSN). The technology can be used to track the location of medical devices needed for inspections or repairs, and it can also be used to detect of a theft of an asset. In an asset-tracking system using WSN, acquiring the location of moving sensor nodes inherently introduces uncertainty in location determination. In fact, the sensor nodes attached to an asset are prone to failure from lack of energy or from physical destruction. Therefore, even if the asset is located within the predetermined area, the asset-tracking application could "misunderstand" that an asset has escaped from the area. This paper classifies the causes of such unexpected situations into the following five cases: 1) an asset has actually escaped from a predetermined area; 2) a sensor node was broken; 3) the battery for the sensor node was totally discharged; 4) an asset went into a shadow area; 5) a sensor node was stolen. We implemented and installed our asset-tracking system in a hospital and continuously monitored the status of assets such as ventilators, syringe pumps, wheel chairs and IV poles. Based on this real experience, we suggest how to differentiate each case of location uncertainty and propose possible solutions to prevent them.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.685-693
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• 2020

This study was performed to compare the differences between total fat area, subcutaneous fat area and visceral fat area according to L1-S1 inter vertebral disc level in asymptomatic Korean patients with non-contrast abdominal CT scan. The location of the maximum fat ratio of the total fat area is the total fat area measured in male L2-3, L3-4, L4-5, female L4-5, and L5-S1. The location showing the maximum fat ratio of the subcutaneous fat area is the subcutaneous fat area measured in male L4-5, and the woman is the subcutaneous fat area measured in L4-5 and L5-S1. The location of the maximum fat ratio of visceral fat area was the visceral fat area measured in L1-2 and L2-3 males, and there was no difference in visceral fat area according to the measured position in females. Although abdominal fat measurement is common at the L4-5 inter vertebral disc level, fat distribution varies widely depending on nationality, race, and gender. Therefore, it is necessary to analyze through the research data which location to choose according to the research purpose, and to mention why the location is appropriate.

• Journal of the Korean Regional Science Association
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• v.40 no.1
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• pp.89-110
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• 2024

REITs are very closely related to real estate management, but there have been no prior studies analyzing the location of REITs assets. Therefore, this study analyzed the location characteristics of REITs assets in two aspects to clarify the location characteristics by using spatial information of REITs assets. First, the characteristics of the type of city where REITs assets are distributed were analyzed, and second, the characteristics of the zoning where REITs assets are distributed were analyzed. As a result of analyzing the characteristics of the city where REITs assets are distributed by type, it was analyzed that in the case of the capital area, both the ratio of cities with REITs assets location and the intensity of REITs assets location (number of REITs assets per city) have location characteristics by city hierarchy in the order of metropolitan city > big city > small and medium-sized city. In the case of non-capital area's metropolitan and large cities, the ratio of REITs assets location cities is similar to that of the capital area, but the location intensity of REITs assets was analyzed to be significantly lower than that of the capital area. As a result of the analysis of REITs assets by type, housing REITs assets tend to be located in the old downtown commercial zoning and the new downtown residential zoning, office REITs assets are characterized by concentration of location in specific commercial zoning of Seoul, and retail REITs assets are located mainly in the old downtown station area. In addition, it was found that logistics REITs assets tend to be located in management zoning, centering on key logistics hub cities in the region.

• The Journal of Information Technology
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• v.5 no.4
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• pp.165-171
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• 2002

We propose Dynamic Circle Location Register (DCLR) scheme where each visiting location register (VLR) has a given fixed circle registration area around itself and has IDs of other VLRs in this circle area. Whenever a terminal moves to another registration area (RA), system computes whether the terminal is located in the current DCLR area and sends the recent location information of terminal to the old or new DCLR according to computing results. Also, according to change DCLR circle dynamically, we can track terminal location by querying DCLR of the current terminal when a call originates. The our scheme solves the HLR bottleneck due to the terminals frequent RA crossings and distributes the registration traffic to each of the local signaling transfer point (LSTP) area in wireless communications (WC)

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.10-15
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• 2005

In the area of mobile communication, Location Based Services (LBS) using the location of mobile terminal to provide their services are rapidly spreading as communication network and terminal evolves. Despite the LBS are highly demanded in high speed internet area, the services are very rare due to the difficulty locating terminals. In this paper, we propose the method to locate terminals in real time and describe its implementation system. The proposed system is designed to collect the information in real time for more than a terminal connecting internet. And, the system shows high performancecollecting and generating location information through simulation tests.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.2
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• pp.135-143
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• 2012

This paper suggests the optimal blood distribution center algorithm that satisfies the minimum total transportation cost and within the allowable distribution time $T^*$. Zhang and Yang proposes shifting the location of each point that has less than the average distance of two maximum distance points from each point. But they cannot decide the correct facility location because they miscompute the shortest distance. This algorithm computes the shortest distance $l_{ij}$ from one area to another areas. Then we select the $v_i$ area to thecandidate distribution center location such that $_{max}l_{ij}{\leq}L^*$ and the $v_i$ such that $l_{ij}-L^*$ area that locates in ($v_i,v_k$) and ($v_j,v_l$) from $P_{ij}=v_i,v_k,{\cdots},v_l,v_j$ path and satisfies the $_{max}l_{ij}{\leq}L^*$ condition. Finally, we decide the candidate distribution area that has minimum transportation cost to optimal distribution area.

• Journal of the Korean Institute of Rural Architecture
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• v.25 no.3
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• pp.17-25
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• 2023

The purpose of this study is to analyze the location and space composition of small elderly care facilities in gyeongsangnam-do and to present a desirable direction for planning small elderly care facilities. As a research method, the location and spatial composition of 82 facilities for elderly care facilities with a capacity of 10 to 29 installed in Gyeongsangnam-do were investigated. In particular, the location, site area, total floor area, and composition of major rooms of small elderly care facilities were analyzed. The results of the survey and analysis are as follows. First, as for location characteristics, 56.1% of the suburban and rural types, 28.1% of the urban area type, and 12.2% of the mountain type were found in order. Second, in the connection between location and spatial composition, stand-alone facilities accounted for 53.7%, and complex types accounted for 46.3%. Third, the average number of admissions was 23.1, and facilities corresponding to the size of 26-29 admissions were the largest at 41.0%. The total floor area per person was 28.3m². Fourth, in terms of the spatial composition of facilities, stand-alone facilities accounted for 53.7%, and complex types accounted for 46.3%. Fifth, by the number of people in the bedroom, 49.4% were installed in the order of a four-person room, 25.0% in a three-person room, 18.7% in a two-person room, and 3.5% in a one-person room. In addition, in the bedroom lifestyle, 84.1% of the bed type and 15.9% of the bed + sitting type were found.

• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.155-162
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• 2019

To reduce the secondary damage caused by leakage accidents in plant piping systems, a constant surveillance system is necessary. To ensure leaks are promptly addressed, the surveillance system should be able to detect not only the leak itself, but also the location of the leak. Recently, research to develop new methods has been conducted using cameras to detect leakage and to estimate the location of leakage. However, existing methods solely estimate whether a leak exists or not, or only provide two-dimensional coordinates of the leakage location. In this paper, a method using multiple cameras to detect leakage and estimate the three-dimensional coordinates of the leakage location is presented. Leakage is detected by each camera using MADI(Moving Average Differential Image) and histogram analysis. The two-dimensional leakage location is estimated using the detected leakage area. The three-dimensional leakage location is subsequently estimated based on the two-dimensional leakage location. To achieve this, the coordinates (x, z) for the leakage are calculated for a horizontal section (XZ plane) in the monitoring area. Then, the y-coordinate of leakage is calculated using a vertical section from each camera. The method proposed in this paper could accurately estimate the three-dimensional location of a leak using multiple cameras.

• Journal of the Economic Geographical Society of Korea
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• v.14 no.3
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• pp.286-306
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• 2011

Based on the announcement by the National Competitiveness Council in 2008, this study analyzed the direction of the changing policy in Seoul Metropolitan Area promoted by the current government and to inquire into such the effect, research was done to study the changes in space demand by companies which respond sensitively to changes in regulation in Seoul Metropolitan Area. In addition, the effect of Seoul Metropolitan Area policy on company location is explored while company location changes and changes in direction of space demand due to easing of regulation in Seoul Metropolitan Area by the current government are examined. Research methods utilized empirical analysis and survey analysis. Empirical analysis utilized statistical data since 1980's. For survey analysis, the effect of changing policy in Seoul Metropolitan Area, which is an exogenous shock, on decision making of the enterprise is considered to derive the direction of demand for company manufacturing lots. The results of the study showed that decision for company location or factory size has been affected greatly by Seoul Metropolitan Area policy and domain regulation and institution to restrict permission area of a manufacturing building from the law of improvement plan of the Metropolitan area were the biggest regulatory policies. Due to easing of regulation in Seoul Metropolitan Area by the current government, the demand for manufacturing lot is expected to increase. In particular, the demand for manufacturing lot is expected to increase centered around Seoul Metropolitan Area and Chungcheong province while demand is expected to decrease in Gangwon province. The reason is because company preference is high for the Seoul Metropolitan Area which has the best transportation/logistics and market conditions in Korea. But in the case of Southeast region and Daegyung region that form exclusive economic zones, changing policy in Seoul Metropolitan Area has little impact. In the case of Seoul Metropolitan Area, demand increase does not occur in the entire area but instead, demand is expected to increase in growth management zones.