• Journal of Convergence for Information Technology
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• v.7 no.2
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• pp.1-9
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• 2017

Recently, the DDoS attack using the amplifier method makes it difficult to distinguish the normal traffic from the normal server and it is difficult to detect even the attack detection. Since the SSDP protocol is a common protocol widely used in IoT devices, it is used as a DDoS amplification attack. In this paper, we analyze the reflector attack of SSDP which is one of the DDoS and suggest a technical proposal to detect and defend against the attack by managing the Mac address of each device. Also, we propose a control structure to protect the reflection attack of SSDP in Home IoT. The efficiency of the proposed system has been verified by performing an experimental attack on the virtual environment.

• MISULJARYO - National Museum of Korea Art Journal
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• v.98
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• pp.200-225
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• 2020

This paper, based on "Minhwa Chaekgeori" paintings from the collection of the National Museum of Korea, identifies and discusses fourteen similar works in domestic and international collections as products of the Seokdang workshop. First, the relevant paintings are identified as products of the workshop known as Seokdang (石堂, literally "stone hall") by the workshop's seal that is stamped on them. Second, analysis of the iconography indicates that the paintings were likely produced in the 1920s. Third, research on certain geographic names and addresses associated with this group of paintings suggests that they might not have been separately commissioned, but are rather examples of partially "ready-made" paintings. Fourth, the paper discusses how the designs of various cultural products in these paintings reflects contemporaneous changes in Korea's diplomatic and commercial relations, i.e., the decline of relations with China and rise of relations with the United States and Europe. Finally, a comparison of the Seokdang chaekgeori paintings with the popular chaekgeori paintings produced by Yi Hyeongrok and Yi Deokyeong in the early twentieth century provides important implications for the succession of tradition and innovation in visual culture.

• Journal of the Health Care and Life Science
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• v.8 no.2
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• pp.135-142
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• 2020

The purpose of this study was to analyze the frequency of use of hospitalization/outpatient care of patients with addresses in Yeongbuk-gu, Gangwon-do to identify the medical demand and status of medical use in Yeongbuk-do. The National Health Insurance Corporation (www.data.go.kr) conducted an analysis of health insurance and medical benefits (inpatient/outpatient) claims data from 2003 to 2017. The order of the highest frequency of chronic disease was ranked from 1st to 60th according to 'Healing Case and %'. In addition, the use of patients at Sokcho Medical Center, the only hospital in the Yeongbuk region, was analyzed at the same time. According to the analysis, the use of outpatient treatment and In-patients in the Yeongbuk area of Gangwon-do is increasing due to chronic non-infectious diseases from the past acute diseases. In particular, it is necessary to expand the functions of schizophrenia and obstetrics and gynecology and to carry out specific health projects necessary for the health care of the local community. Through this, we should improve the quality of life in Yeongbuk, Gangwon Province.

• Journal of Internet of Things and Convergence
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• v.10 no.2
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• pp.109-114
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• 2024

Enterprise storage systems that require high data reliability are applying RAID (Redundant Array of Independent Disks) systems to recover from data loss and failure. In particular, RAID 5 ensures space efficiency and reliability by distributing parity across multiple storage devices. However, when storage devices have different capacities, RAID is built based on the smallest capacity storage device, resulting in wasted storage space. Therefore, research is needed to solve this resource management problem. In this paper, we propose a method for RAID grouping of each independent NAND flash memory block in a RAID consisting of SSD (Solid State Disk) with external SSDs as well as internal SSDs. This method is divided into a policy for delivering block information inside SSDs to the RAID system and a policy for RAID grouping of physical addresses delivered from the RAID system. This method allows us to maintain a RAID that does not waste resources when SSDs of different capacities are grouped into RAID5. Finally, we demonstrate the effectiveness of the proposed method through experiments.

• Clinical and Experimental Pediatrics
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• v.49 no.6
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• pp.643-647
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• 2006

Purpose : Recently, incidences of chronic cough with allergic disease have been increased. The identification of specific allergens for chronically coughing children is significant for diagnosis, proper treatment and prevention. The aim of this study was to identify significant contributors for sensitization in chronically coughing children. Methods : A total of 106 children, aged 1-6 years, visiting for chronic cough(>3 weeks), were tested for inhalant multiple allergosorbent assay(MAST), eosinophil count and total IgE. Parents completed a questionnaire on past history of atopy(infantile eczema) and bronchiolitis, family history of allergy, breastfeeding, smoking, pets and floor coverings at home. Results : Significant contributors for sensitization were : age(4-6 years), infantile eczema, positive family history of allergy and smoking by family. Conclusion : We were able to identify significant contributors for sensitization in chronically coughing children.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.2
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• pp.16-27
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• 2015

The parcels of land alteration by existing manual work was very inefficient in terms of time and costs. Especially it caused many difficulty in estimating compensation since the work didn't take into account the range of adjoining zone to road. This study selected Gimje City of Jeollabuk-Do as a study site and could analyze the numbers and areas of parcels of land alteration considering the range of adjoining zone to road based on cadastral maps and wide road layers from new address system. Also this study applied a fuzzy membership function according to occupation ratio to road, and analyzed compensation by the range of adjoining zone to road using individual public land price information of the parcels for land alternation. Especially, the change aspect of public and private parcels could be investigated by the range of adjoining zone to road according to the fuzzy membership function. And this study could provide very efficient data in determining the priority of the parcels for land alternation through calculating compensation of the parcels for land alternation by Eup Myeong Dong according to the range of adjoining zone to road.

• Journal of Korea Spatial Information System Society
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• v.11 no.2
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• pp.143-150
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• 2009

Spatial data warehouses are a system managing manufactured data through ETL step with extracted spatial data from spatial DBMS or various data sources. In load period, duplicated spatial data in the same subject are not useful in extracted spatial data dislike aspatial data and waste the storage space by the feature of spatial data. Also, in case of extracting source data on heterogeneous system, as those have different spatial type and schema, the spatial extract method is required for them. Processing a step matching address about extracted spatial data using a standard Geocoding DB, the exiting methods load formal data set. However, the methods cause the comparison operation of extracted data with Geocoding DB, and according to integrate spatial data by subject it has problems which do not consider duplicated data among heterogeneous spatial DBMS. This paper proposes efficient extracting method to integrate update query extracted from heterogeneous source systems in data warehouse constructer. The method eliminates unnecessary extracting operation cost to choose related update queries like insertion or deletion on queries generated from loading to current point. Also, we eliminate and integrate extracted spatial data using update query in source spatial DBMS. The proposed method can reduce wasting storage space caused by duplicate storage and support rapidly analyzing spatial data by loading integrated data per loading point.

• The KIPS Transactions:PartD
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• v.11D no.1
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• pp.11-22
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• 2004

As random access memory chip gets cheaper, it becomes affordable to realize main memory-based database systems. Consequently, reducing cache misses emerges as the most important issue in current main memory databases, in which CPU speeds have been increasing at 60% per year, compared to the memory speeds at 10% per you. In this paper, we design and implement a main-memory database system for real-time mobile GIS. Our system is composed of 5 modules： the interface manager provides the interface for PDA users； the memory data manager controls spatial and non-spatial data in main-memory using virtual memory techniques； the query manager processes spatial and non-spatial query : the index manager manages the MR-tree index for spatial data and the T-tree index for non-spatial index : the GIS server interface provides the interface with disk-based GIS. The MR-tree proposed propagates node splits upward only if one of the internal nodes on the insertion path has empty space. Thus, the internal nodes of the MR-tree are almost 100% full. Our experimental study shows that the two-dimensional MR-tree performs search up to 2.4 times faster than the ordinary R-tree. To use virtual memory techniques, the memory data manager uses page tables for spatial data, non- spatial data, T-tree and MR-tree. And, it uses indirect addressing techniques for fast reloading from disk.

• The Transactions of the Korea Information Processing Society
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• v.5 no.10
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• pp.2627-2640
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• 1998

In this paper, we analyze the performance of the virtual cell system[1] for the transmission of IP datagrams in mobile computer communications. A virtual cell consistsof a group of physical cells shose base stationsl are implemented b recote bridges and interconnected via high speed datagram packet switched networks. Host mobility is supported at the data link layer using the distributed hierachical location information of mobile hosts. Given mobility and communication ptems among physical cells, the problem of deploying virtual cells is equivalent to the optimization cost for the entire system where interclster communication is more expesive than intracluster communication[2]. Once an iptimal partitionof disjoint clusters is obtained, we deploy the virtual cell system according to the topology of the optimal partition such that each virtual cell correspods to a cluser. To analyze the performance of the virtual cell system, we adopt a BCMP open multipel class queueing network model. In addition to mobility and communication patterns, among physical cells, the topology of the virtual cell system is used to determine service transition probabilities of the queueing network model. With various system parameters, we conduct interesting sensitivity analyses to determine network design tradeoffs. The first application of the proposed model is to determine an adequate network bandwidth for base station networking such that the networks would not become an bottleneck. We also evaluate the network vlilization and system response time due to various types of messages. For instance, when the mobile hosts begin moving fast, the migration rate will be increased. This results of the performance analysis provide a good evidence in demonsratc the sysem effciency under different assumptions of mobility and communication patterns.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.192-199
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• 2016

This article examines the location strategies of coffee franchises in Gyeonggi province. Due to its large population, broad area, and diverse industrial structure, Gyeonggi province is an ideal dataset for empirical testing of the location strategies. We collect the addresses of five major coffee franchises stores, convert them into geographic coordinates using Google Maps Geocoding API, and compute Haversine distances both between stores of the same franchise and between stores of different franchises. This novel approach leads to three discoveries. First, coffee-consuming age population is positively related to the number of stores and more strongly for commercial areas with a large floating population. Second, one third of Starbucks stores have another Starbucks store within a radius of 300m, which empirically confirms the 'Focused Destroy Strategy' of Starbucks that has multiple stores in central business districts. Third, for 80% of Starbucks stores, we can find Ediya stores within 500m, which supports Ediya's 'Next-to-Starbucks Strategy'. Our research methods can be efficiently applied to the analyses of other retail businesses such as convenience stores, fast food restaurants, and mobile phone shops.