• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.676-678
• /
• 2003

Recently, in according as rapid improvement of telecommunication markets and wireless internet technology, Location- Based Services (LBS) have been discussed as new 'Killer' application. The purpose of LBS is to determine location of user through mobile handset and to offer location information service to end-user. This paper has suggested an efficient transmission scheme of maps data as one of the important content services relating to data transmission of LBS in mobile environment. The basic system consists of three parts : (1) GIS (Geographic Information System) Server for storing, processing and handling map data, (2) Middleware Server for transmitting of map data by request of client, and (3) Client for requesting map data to Server and displaying them on handset. Also, in order to transmit map data, we are to expand WKB (Well Known Binary) in conformance to Simple Feature Specification of OGC (Open GIS Consortium), and increase efficiency of data transmission by developing trans mission data format to be able to transmit lightweight data and considering data compression technology.

• Journal of Korea Multimedia Society
• /
• v.18 no.7
• /
• pp.818-826
• /
• 2015

With the rapid interest in Geographic Information System (GIS) contents, a large volume of valuable GIS dataset has been distributed illegally by pirates, hackers, or unauthorized users. Therefore the problem focus on how to protect the copyright of GIS vector map data for storage and transmission. But GIS vector map data is very large and current data encryption techniques often encrypt all components of data. That means we have encrypted large amount of data lead to the long encrypting time and high complexity computation. This paper presents the selective encryption scheme using hybrid transform for GIS vector map data protection to store, transmit or distribute to authorized users. In proposed scheme, polylines and polygons in vector map are targets of selective encryption. We select the significant objects in polyline/polygon layer, and then they are encrypted by the key sets generated by using Chaotic map before changing them in DWT, DFT domain. Experimental results verified the proposed algorithm effectively and error in decryption is approximately zero.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.9 no.2
• /
• pp.109-115
• /
• 2014

Analyzing large scale data has become an important activity for many organizations. Since MapReduce is a promising tool for processing the massive data sets, there are increasing studies to evaluate the performance of various algorithms related to MapReduce. In this paper, we first develop a simulation framework that includes MapReduce workload model, data center model, and the model of data access pattern. Then we propose two algorithms that can reduce the energy consumption of MapReduce systems. Using the simulation framework, we evaluate the performance of the proposed algorithms under different application characteristics and configurations of data centers.

• Journal of Cadastre & Land InformatiX
• /
• v.47 no.2
• /
• pp.49-60
• /
• 2017

Recently, the use of mashup that integrates real-time data with spatial data such as tiled map and satellite imagery has been increased significantly. As the use of mashup has been extended to various fields of O2O, LBS, Smart City, and Autonomous Driving, the performance of mashup has become more important. Therefore, this study aims to compare and analyze the performance of various map platforms, when large amounts of real-time data are integrated with spatial data. Specifically, we compare the performance of most popular map platforms available in Korea, such as Google Maps, OpenStreetMap, Daum Map, Naver Map, olleh Map, and VWorld. We also compare the performance using most common web browsers of Chrome, Firefox and Internet Explorer. In the performance analysis, we measured and compared the initialization time of basic map and the mashup time of real-time data for the above map platforms. From analysis results, we could find that Google Maps, OpenStreetMap, VWorld, and olleh Map platforms showed a better performance than the others.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.9
• /
• pp.1865-1872
• /
• 2009

This study suggests a method for extending XMDR to integrate and search legacy system. This extension blends MSO(Meta Semantic Ontology) for the management of metadata, ML(Meta Location) for the management of location information, and Topic Map which is the standard language used to represent semantic web. This study refers to it as TMDR(Topic Map MetaData Registry). As an intelligent layer, Topic Map functions like an index. However, if the data frequently changes, the efficiency of Topic Map may drop. To solve this problem, the proposed system represents the relation among metadata, the relation among real data, and the relation between metadata and real data as Topic Map. The represented Topic Map proposes a method to reduce the changing relation among real data caused by the relation among metadata.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.19 no.10
• /
• pp.1075-1082
• /
• 2009

Using GIS data of C-si as basic data when making noise map of road traffic, we estimated exactly the noise excess areas and consequently suggested the population and the area exposed to road traffic noise accurately. We made 3D noise map to assess regional distribution of noise quantitatively. The noise map consists of noise prediction model based on data base such as traffic volume and speed changes for estimating quantitatively the noise and 3D urban space model which includes locations of noise sources, 3D buildings, topography and roads. We made noise standard map according to land use conditions and compared this map to road traffic noise map, and consequently made excess noise map. Using excess noise map, we assessed areas which exceed environmental noise level standards and noise guidelines quantitatively and effectively through GIS spatial analysis, and consequently more accurate noise exposed area and noise exposed population could be estimated. To show buildings' outer walls noise exposure, we analyzed 3D urban noise distributions using 3D-analysis of GIS.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.1056-1059
• /
• 2003

Self-Oranizing Map(SOM) is an unsupervised neural network providing cluster analysis of high dimensional input data. The output from the SOM is represented in map that help us to explore data. The weak point of conventional SOM is when the map is large, it take a long time to train the data. The computing time is known to be O(MN) for trainning to find the winning node (M,N are the number of nodes in width and height of the map). This paper presents a new method to reduce the computing time by creating new map. Each node in a new map is the centroid of nodes' group that are in the original map. After create a new map, we find the winning node of this map, then find the winning node in original map only in nodes that are represented by the winning node from the new map. This new method is called "High Speed Self-Oranizing Map"(HS-SOM). Our experiment use HS-SOM to cluster documents and compare with SOM. The results from the experiment shows that HS-SOM can reduce computing time by 30%-50% over conventional SOM.

• Journal of Digital Contents Society
• /
• v.14 no.3
• /
• pp.313-321
• /
• 2013

In recent, proliferation of mobile smart devices have led to big-data era, the importance of location-based services is increasing due to the exponential growth of trajectory related data. In order to process trajectory data, parallel processing platforms such as cloud computing and MapReduce are necessary. Currently, the researches based on MapReduce are on progress, but due to the MapReduce's properties in using batch processing and simple key-value structure, applying MapReduce framework for real time LBS is difficult. Therefore, in this research we propose a suitable system design on efficient indexing and search techniques for real time service based on detailed analysis on the properties of MapReduce.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.27 no.2
• /
• pp.235-247
• /
• 2009

Map is information media for human life. Recently, innovative map making technology has been developed and most updated various data are provided to map users. In consequence, use of maps is rapidly increasing in various applications. One of the examples is car navigation map because navigation maps provide reliable and necessary information with convenient way. Therefore, maps are to be changed to user-oriented from map making-oriented design. The main goal of spatial data infrastructure is to allow various users to access the real world information easily for decision making. However, most of the digital maps are focused on map making aspect such as providing up-to-date data, acquisition of accurate data with state-of-the-art technology, and addition of layers (For example, ortho-images and DEMs). If map data processing tools are to be provided with the digital maps, users could utilize maps for decision making without professional software or knowledge. Therefore, objective of this paper is to propose scheme of the digital map data processing service with application examples.

• Economic and Environmental Geology
• /
• v.32 no.5
• /
• pp.503-517
• /
• 1999

The purpose of this study is to verfify a more effecive techique for calculating geothermal gradient. this study examines 370 data of temperature-logging having been collected since 1985. The daya are divided into three different grades grades according to the type of temperature-depth plots: 204 data show typical linear gradient (Grade A); 126 data do not explicitily show the gradient becase of various external effects such as water flow (Grade B); and the rest 40 data do not show the gradient at all (Grade D). The new technique for calculating geothermal gradient is to be required to use Greade-B data more effctiviely. This new technique includes (1) calculating the independer depth of atmospheric temperature in the earth; (2) drawing a distribution map of subsurface tempurature by using the distribution map of subsurface temperature by using Grade-A data at the independent depth; and (3) recalculating geothermal gradient of Grade-B data by using the distrbution map of subsurface temperature, borehole depth, and bottom temperature of Grade-B data by using the distribution map of subsurface temperature, borehole depth, and bottom temperature of Grade-B data. As a result, 330 data-both Grade-A and Grade-B data--can be used to draw a distribution map of hot spradient. The map clearly distinguishes anomaly areas, and helps interpret their relations to the distribution of hot springs, geology, geological structures, and geophysical anomaly areas. These new results reveal that the average of geothermal in south Korea is 25.6$^{\circ}C$/km, when calculated to the Kriging method.