• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.119-126
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• 2004

Location management is very important issue in wireless communication system to trace mobile users' exact location. In this study, we propose a dynamic location area management scheme which determines the size of dynamic location area considering each user's characteristic. In determining the optimal location area size, we consider the measurement data as well as the historical data, which contains call arrival rate and average speed of each mobile user. In this mixture of data, the weight of historical data is derived by linear searching method which guarantees the minimal cost of location management. We also introduce the regularity index which can be calculated by using the autocorrelation of historical data itself. Statistical validation shows that the regularity index is the same as the weight of measurement data. As a result, the regularity index is utilized to incorporate the historical data into the measurement data. By applying the proposed scheme, the location management cost is shown to decrease. Numerical examples illustrate such an aspect of the proposed scheme.

• IE interfaces
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• v.18 no.4
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• pp.382-389
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• 2005

Location management is very important issue in wireless communication system to trace mobile users' exact location. In this study, we propose a dynamic location area management scheme which determines the size of dynamic location area considering each user's characteristics. In determining the optimal location area size, we consider the measurement data as well as the historical data, which contains call arrival rate and average speed of each mobile user. In this mixture of data, the weight of historical data is derived by linear searching method which guarantees the minimal cost of location management. We also introduce the regularity index which can be calculated by using the autocorrelation of historical data itself. Statistical validation shows that the regularity index is the same as the weight of measurement data. As a result, the regularity index is utilized to incorporate the historical data into the measurement data. By applying the proposed scheme, the location management cost is shown to decrease. Numerical examples illustrate such an aspect of the proposed scheme.

• The KIPS Transactions:PartD
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• v.18D no.4
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• pp.225-236
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• 2011

Various applications of LBS (Location Based Services) are being developed to provide the customized service depending on user's location with progress of wireless communication technology and miniaturization of personalized device. To effectively process an amount of vehicles' location data, LBS requires the techniques such as vehicle observation, data communication, data insertion and search, and user query processing. In this paper, we propose the historical location index, GIP-FB (Group Insertion tree with Flexible Buffer Node) and the flexible buffer node technique to adjust the cost of data insertion and search. the designed GIP+ based index employs the buffer node and the projection storage to cut the cost of insertion and search. Besides, it adjusts the cost of insertion and search by changing the number of line segments of the buffer node with user defined time interval. In the experiment, the buffer node size influences the performance of GIP-FB by changing the number of non-leaf node of the index. the proposed flexible buffer node is used to adjust the performance of the historical location index depending on the applications of LBS.

• Journal of Information Processing Systems
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• v.12 no.2
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• pp.263-274
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• 2016

The exceptional development of electronic device technology, the miniaturization of mobile devices, and the development of telecommunication technology has made it possible to monitor human biometric data anywhere and anytime by using different types of wearable or embedded sensors. In daily life, mobile devices can collect wireless body area network (WBAN) data, and the co-collected location data is also important for disease analysis. In order to efficiently analyze WBAN data, including location information and support medical analysis services, we propose a geohash-based spatial index method for a location-aware WBAN data monitoring system on the NoSQL database system, which uses an R-tree-based global tree to organize the real-time location data of a patient and a B-tree-based local tree to manage historical data. This type of spatial index method is a support cloud-based location-aware WBAN data monitoring system. In order to evaluate the proposed method, we built a system that can support a JavaScript Object Notation (JSON) and Binary JSON (BSON) document data on mobile gateway devices. The proposed spatial index method can efficiently process location-based queries for medical signal monitoring. In order to evaluate our index method, we simulated a small system on MongoDB with our proposed index method, which is a document-based NoSQL database system, and evaluated its performance.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.2
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• pp.75-83
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• 2019

Using geographical indication, a type of source identification, can effectively promote local specialty agricultural products of superior quality, by identifying the specific geographic location or origin of the produce. Agricultural products can be registered using the geographical indication by describing the product's relation to its geographical origin including the reputation and quality. However, this indication has no objective standards to qualify goods as agricultural specialty products. The purpose of this study is to suggest basic criteria to define the characteristics and criteria of agricultural specialties based on a quantitative evaluation method. To propose this basic standard, we used the proportion of arable land to denote the major production areas and the location quotient (LQ) index to grasp the extent of the specialty of a product. The results show that the average LQ values of registered agricultural products, particularly apples, pears, and garlic, are 3.26, 8.01, and 2.82, respectively. This indicates that they are more specialized than produce from other areas that have not registered for a geographical indication. Low LQ values were found in some areas with registered rice geographical indications, which are also more focused on their historical reputation as the main rice producing areas. Considering the agricultural specialty of products, the recommendation is that the producing proportion should be over 1% of the national scale and over 10% of the province scale, and the LQ value should be over 2.0. This recommendation is not a requirement, but the criteria can prove to be useful in identifying a higher range of specialized agricultural products.

• Korean Journal of Remote Sensing
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• v.38 no.2
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• pp.179-188
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• 2022

Global warming causes climate change and increases extreme weather events worldwide, and the occurrence of heatwaves and droughts is also increasing in Korea. For the monitoring of extreme weather, various satellite data such as LST (Land Surface Temperature), TCI (Temperature Condition Index), NDVI (Normalized Difference Vegetation Index), VCI (Vegetation Condition Index), and VHI (Vegetation Health Index) have been used. VHI, the combination of TCI and VCI, represents the vegetation stress affected by meteorological factors like precipitation and temperature and is frequently used to assess droughts under climate change. TCI and VCI require historical reference values for the LST and NDVI for each date and location. So, it is complicated to produce the VHI from the recent satellite GK2A (Geostationary Korea Multi-Purpose Satellite-2A). This study examined the retrieval of VHI using GK2A AMI (Advanced Meteorological Imager) by referencing the historical data from VIIRS (Visible Infrared Imaging Radiometer Suite) NDVI and LST as a proxy data. We found a close relationship between GK2A and VIIRS data needed for the retrieval of VHI. We produced the TCI, VCI, and VHI for GK2A during 2020-2021 at intervals of 8 days and carried out the interpretations of recent extreme weather events in Korea. GK2A VHI could express the changes in vegetation stress in 2020 due to various extreme weather events such as heatwaves (in March and June) and low temperatures (in April and July), and heavy rainfall (in August), while NOAA (National Oceanic and Atmospheric Administration) VHI could not well represent such characteristics. The GK2A VHI presented in this study can be utilized to monitor the vegetation stress due to heatwaves and droughts if the historical reference values of LST and NDVI can be adjusted in a more statistically significant way in the future work.

• Journal of the Korean Institute of Rural Architecture
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• v.13 no.1
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• pp.9-20
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• 2011

This study is designed to examine characteristics and types of basic landscape design established by 7 local governments in Jeollanam-do and its availability as the index of landscape administration and present a guideline with view landscape plan of local governments. The results of this study are described below. In case of view landscape, while Korean cities have not many historical assets like landmark, they have locational characteristics with mountain or coast in the center or surroundings of downtown. Therefore, since view landscape has many cases of restricting individual property rights as well as having a value as public property of city which makes recognition of sharing city, it is very sensitive problem and establishing guideline of it is needed. But, it was found that view landscape plan of local governments established location of view spot with the nature of relief viewing downtown or coast from high spot. Selection of viewing objects in view plan require deciding an object as the public property of city and big cities require selection from the zone and small cities must select 1~2 spots from the viewpoint of whole downtown. 3~4 view spots of middle and distant views which makes city community centering around the subject of view must be selected through enough discussion and in case of natural landscape, View shaft or visible rays require setting of range that 30% of viewing objects is seen. View spot or viewing objects should be selected over twice as extra spots through public hearing and civil participation as the process.