• Journal of Information Technology Application
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• v.3 no.4
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• pp.63-92
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• 2001

This paper makes an attempt to look at the process of automatically generating an application software system based on the Entity-Relationship (E-R) model. Basically, the process consists of five steps as follows: First, the designer develops an E-R model of an real-world system. Second, the software generator automatically generates a stereo-type application system. Third, the generator produces database schema and link information between application programs. Fourth, the designer designs the user interface including menu, screen design and so on. Finally, the generator completes the process integrating all the elements of an application system. Five basic program generation rules, three extended rules and a database generation rule have been suggested. By following each rule with the generator, the designer can build an application with an extremely efficient manner compared with traditional approaches. A case study has been included in order to show the applicability of the automated software generation process suggested in this paper. It has been demonstrated from the case study that the idea of applying an automated generator in systems development based upon the E-R model worked well.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.2
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• pp.95-103
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• 2007

An analytical closed-form solution for wave propagation velocity and damping in saturated porous media is presented in this paper The fully coupled field model with compressible solid Brains and pore water were used to derive this solution. An engineering approach for the analysis of fully saturated porous media was adopted and closed-form solutions for one dimensional wave propagation in a homogeneous domain were derived. The solution is highly versatile in that it considers compression of the solid grains, compression of the pore water, deformation of the porous skeleton, and spatial damping and can be used to compute wavespeeds of first and second kind and damping coefficients in various geologic materials. This solution provides a means of analyzing the influence of material property variations on wavespeed and attenuation. In Part 2 of this work the theoretical solution is incorporated into the numerical code and the code is used in a parametric study on wave propagation velocity and damping.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.5
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• pp.185-192
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• 2011

In this paper, we simulate and analyze performance of iterative coding scheme, double binary turbo code, for high speed power line communication (PLC) systems. PLC system has hostile environment for high speed data transmission, so error correction method is necessary to compensate effects of PLC channel. We employ the PLC model proposed by M. Zimmerman and Middleton Class A interference model, and system performance is evaluated in terms of bit error rate (BER). From the simulation results, we confirm double binary turbo code provides considerable coding gains to PLC system and BER performance is significantly improved as the number of iteration increase. It is also confirmed that BER performance increases as code rate is lager, while it decreases as the code rate is smaller.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.5
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• pp.27-33
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• 2014

As UCI (Universal Content Identifier) identification system becomes a national standard for content distribution, many digital contents are distributed through UCI identification system. However, problems associated with copyright infringement and copyright contracts occur due to lack of copyright information. ICN (Integrated Copyright Number), a code system developed for copyright management, includes copyright-related information for the purposes of usage settlement and accounting, illegal usage monitoring, and content filtering. ICN, however, has no information about distribution and content properties. Therefore, the linkage and integration between UCI and ICN can be a basis for the transparent and effective distribution of digital contents. In this paper, we propose a model for linking and integrating UCI and ICN, developing the efficiency in the value chain of each identified system by analyzing political factors and key technical elements between the two identification systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.14-19
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• 2020

This paper proposes a precise drone-positioning technique using a differential global positioning system (DGPS). The proposed system consists of a reference station for error correction data production, and a mobile station (a drone), which is the target for real-time positioning. The precise coordinates of the reference station were acquired by post-processing of received satellite data together with the reference station location data provided by government infrastructure. For the system's implementation, low-cost commercial GPS receivers were used. Furthermore, a Zigbee transmitter/receiver pair was used to wirelessly send control signals and error correction data, making the whole system affordable for personal use. To validate the system, a drone-tracking experiment was conducted. The results show that the average real-time position error is less than 0.8 m.

• Journal of Korea Multimedia Society
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• v.12 no.3
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• pp.427-435
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• 2009

Users are able to search and read interesting items and hence click hyperlink linked to the item which is detailed content unit such as menu, login, news, video, etc. Small screen like mobile device is very difficult to viewing all web contents at once. Browsing and searching for interesting items by scrolling to left and right or up and down is discomfort to users in small screen. Searching and displaying directly the item preferred by users can reduces difficulty of interface manipulation of mobile device. To archive it, web contents based on desktop will be segmented on a per-item basis which component unit of web contents. Most segment algorithms are based on segment method through analysis of HTML code or mobile size. However, it is difficult to extract item blocks. Because present web content is getting more complicated and diversified in structure and content like web portal services. A web content segment algorithm suggested in this paper is based on extracting item blocks is component units of web contents.

• Journal of Navigation and Port Research
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• v.28 no.1
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• pp.23-29
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• 2004

This paper deals with Reed-Solomon Coding for EUROFIX system EUROFIX is an integrated navigation and communication system, which combines Differential GNSS and Loran-C EUROFIX transmits DGNSS(Differential Global Navigation Satellite Systems) (data by pulse position modulation of Loran-C pulses. Loran-C system is regarded as a satellite backup system in recent. And now, it is important to detect and correct much errors in communication systems. Error corrections or correction algorithm is actively studied nowadays because of this. In this paper, we study and design encoder and decoder of Reed Solomon Code using Finite Galois Field Fourier Transformation for error corrections in EUROFIX data transmission. Through extensive simulation, the designed Reed Solomon code is shown to be effective for error correction in EUROFIX data transmission.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.6
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• pp.1058-1064
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• 2009

According to development of Information Technology and generalization of internet, practical use field of geography information became various. Therefor various Geographic Information System (GIS) constructed to manage geography information efficiently. However, geography information data of various form is depending on graphic authorizing tool of various form being not normalized each other. So, OGC(Open Geospatial Consortium) proposed GML(Geography Markup Language) that describe normalized geography information data that can apply mutually and W3C proposed SVG(Scalable Vector Graphics) of vector base. In this paper creates GML data of XML base for geography information data processing to vector graphic object, and design and implementation of GML document editing and translation system that define code converter that create GML document through created graphic objects and change vector graphic to logic structure of XML base.

• The Transactions of the Korea Information Processing Society
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• v.6 no.8
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• pp.2188-2195
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• 1999

This paper proposes a new call admission control scheme utilizing an inverse fuzzy vector quantizer(IFVQ) and neuralnet, which combines benefits of IFVQ and flexibilities of FCM(Fuzzy-C-Means) arithmetics, to decide whether a requested call not to be trained in learning phase to be connected or not. The system generates the estimated traffic pattern for the cell stream of a new call, using feasible/infeasible patterns in codebook, fuzzy membership values that represent the degree to which each pattern of codebook matches input pattern, and FCM arithmetics. The input to the NN is the vector consisted of traffic parameters which are the means and variances of the number of cells arriving in decision as to whether to accept or reject a new call depends on whether the NN is used for decision threshold(+0.5). This method is a new technique for call admission control using the membership values as traffic parameter which declared to CAC at the call set up stage, and this is valid for a very general traffic model in which the calls of a stream can belong to an unlimited number of traffic classes. Through the simulations, it is founded the performance of the suggested method outperforms compared to the conventional NN method.

• The KIPS Transactions:PartC
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• v.12C no.6 s.102
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• pp.855-864
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• 2005

In this paper, we propose an intrusion detection system(IDS) architecture which can detect and respond against the generation of abnormal traffic such as malicious code and Internet worms. We model the system, design and implement a simulator using OPNET Modeller, for the performance analysis on the response capacity of alert information in the proposed system. At first, we model the arrival process of alert information resulted from abnormal traffic. In order to model the situation in which alert information is intensively produced, we apply the IBP(Interrupted Bernoulli Process) which may represent well the burstiness of traffic. Then we perform the simulation in order to gain some quantitative understanding of the system for our performance parameters. Based on the results of the performance analysis, we analyze factors which may hinder in accelerating the speed of security node, and would like to present some methods to enhance performance.