• Journal of Korean Library and Information Science Society
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• v.40 no.2
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• pp.139-159
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• 2009

This study is to develop knowledge base system for query extension to the user oriented information retrieval. This study has survey the theories of the concept-based information retrieval method and statistic based information retrieval method. In the construction method of knowledge base, the common hypothesis is that the emergence of related term is the frequency of simultaneous emergence of a set of documents. Using the subject index file algorithms and the 'and' operator of boolean logic based on this hypothesis, this study builds the knowledge base. In this research experiment, a subject of knowledge base is education. Using the book of the Introduction to Education, two experimental knowledge base systems is constructed by the different indexing method. One system has constructed by controlled language indexing method, and another system has constructed by natural language indexing method. The performance of two knowledge base system is evaluated.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.2
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• pp.107-118
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• 2010

This paper proposes a digital forensic method to a file creation transaction using a journal file($LogFile) on NTFS File System. The journal file contains lots of information which can help recovering the file system when system failure happens, so knowledge of the structure is very helpful for a forensic analysis. The structure of the journal file, however, is not officially opened. We find out the journal file structure with analyzing the structure of log records by using reverse engineering. We show the digital forensic procedure extracting information from the log records of a sample file created on a NTFS volume. The related log records are as follows: bitmap and segment allocation information of MFT entry, index entry allocation information, resident value update information($FILE_NAME, $STANDARD_INFORMATION, and INDEX_ALLOCATION attribute etc.).

• The KIPS Transactions:PartB
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• v.15B no.6
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• pp.543-552
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• 2008

ATIS(Advanced Traveler Information System) is the system to offer a real-time traffic information or traffic situation for the benefit of the client. One of traffic information collection methods for ATIS research is the method of image analysis. The method is divided into two : one is the method to set two loop detectors at the area and the other is the method detecting the vehicle through an image analysis. In this paper, we propose a real-time traffic information collection system to mix two methods. The system installs multiple virtual detection lines and traces the location of the vehicle. Use of multiple virtual detection lines supplements the defect of the method of loop detectors. And we drew a representative pixels in the detecting area and used it for image analysis. This is to solve the problem of time delay which increases as the image size increases. We gathered traffic images and experimented using the system and got 92.32% of detection accuracy.

• Proceedings of the Korea Association of Information Systems Conference
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• 2005.12a
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• pp.307-313
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• 2005

According to the Policy for ' e-Korea construction ' of Korean government, investment of information system during the Past decay are dramatically increasing. More than a half of this investment is cost of hardware infrastructure. So, accurate hardware sizing are essential for higher efficiency of investment. Accurate hardware sizing benefits are generally viewed in toms of the avoidance of excess equipment and lost opportunity costs by not being able to support business needs. Unfortunately, however, little research effort to make the hardware sizing methodology are doing. We propose a sizing method for information system in public sector. This method is determinated empirical study that are gathering and analyzing cases, making method and reviewing expert. Finally we are proposed calculating method for hardware components that is CPU, memory, internal and external disk according to the application system type which is OLTP, Web, WAS. Our study certainly will act as a catalyst for higher investment-efficiency of the future information programs in public sector.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2435-2439
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• 2005

In case of visual sensing systems with multiple mirrors, systematic errors need to be reduced by the system calibration and the mirror position adjustment in order to enhance system measurement accuracy. In this paper, a self calibration method is presented for a visual sensing system designed to measure the three-dimensional information in deformable peg-in-hole tasks. It is composed of a CCD camera and a series of mirrors including two pyramidal mirrors. By using an image of the inner pyramidal mirror taken by the system, the error parameters of the inner pyramidal mirror could be calibrated or adjusted. Also the influence of the plane mirrors is investigated.

• Journal of information and communication convergence engineering
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• v.3 no.4
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• pp.172-175
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• 2005

In this paper, a new method to get the optimum channel capacity of a Multiple-Input Multiple­Output (MIMO) system is presented. The proposed method exploits the diagonal structure of channel matrix to maximize the channel capacity. The diagonal format of the channel matrix is formed by multiplying the transmitted signal with the pre-compensated channel PCC) matrix. Numerical simulations show that the proposed method exploiting the diagonal structure of channel matrix could significantly increase the system capacity compared with the system without applying the diagonal structure of channel matrix.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.3B
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• pp.158-164
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• 2012

Heterogeneous Network and CSG cell are hot issues in the 3GPP LTE/LTE-Advanced system. In this paper, we analyze the system information measurement methods which are essential for handover to CSG cell. Since there have been no sufficient discussion about this problem, we present and analyze five possible solutions. Moreover, we propose a novel solution to reduce system information measurement delay. In the proposed Autonomous Measurement with Parallel Small Gap(AMPSG) method, the UE measures system information of neighbor cells in a parallel manner. As a result, the proposed method shows better delay performance. Therefore, the proposed AMPSG method can reduce handover delay since the UE have to measure the system information of neighbor cells before CSG handover decision.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.11
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• pp.1095-1101
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• 2006

The clean tube system was developed as a means of transferring air-floated wafers inside a closed tube filled with super clean air. This paper presents a wafer position sensing method in the clean tube system, where the photo proximity sensors are used. The first presented method uses the two positions sensed lately in order to compute the wafer center position. The next method uses the latest sensed position and the next latest position compensated with the information of the wafer velocity. The third method uses the kalman filter, which enable us to use all the previous sensing information. The simulation results are compared to show results of the presented method. In addition, the paper presents a control method to stop the wafer at the center of the unit in the clean tube system. The experimental clean tube system worked successfully with the applying the both presented methods of sensing and control.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.1
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• pp.68-86
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• 2015

Future wireless network aims to integrate different radio access networks (RANs) to provide a seamless access and service continuity. In this paper, a new resource denotation method is proposed in the WLAN and LTE heterogeneous networks based on a concept of spectral bandwidth mapping. This method simplifies the denotation of system resources and makes it possible to calculate system residual capacity, upon which an economic model-based network selection algorithm is designed in both under-loaded and over-loaded scenarios in the heterogeneous networks. The simulation results show that this algorithm achieves better performance than the utility function-based access selection (UFAS) method proposed in [12] in increasing system capacity and system revenue, achieving load balancing and reducing the new call blocking probability in the heterogeneous networks.

• Journal of the Korean Society for information Management
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• v.16 no.4
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• pp.75-94
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• 1999

Indexing is a prerequisite function for the information retrieval system in order to retrieve the information of the documents effectively which are saved in database. As a digital data increases in accordance with the development of a computer, the numbers of literatures to be saved in database have also been increased in a large volume. To retrieve such documents of large volume, a lot of system resources and processing time will be required. In this paper, we suggest a advanced indexing method using text partition. This method can retrieve the documents of large volume in short processing time. We applied this suggested indexing method to real information retrieval system, and proved its excellent functions through the demonstration.