• The KIPS Transactions:PartB
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• v.14B no.1 s.111
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• pp.5-12
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• 2007

This paper gives a novel approach that can be represented an image efficiently with its region and shape information together. To do this, we introduced a region-centralized shape descriptor(RCSD) that the size of region only exists at a center point. RCSD consists of circles with three parameters, the distance and the angle between the tenter points, and the diameter, respectively We verified the RCSD parameters to have an information of shape. We can be proved this by reconstructing the shape from the given parameters and evaluated the difference between the its image and the original one. To get this image, we find the estimated points on the contour from the parameters, and connect them by using an interpolation. According to the evaluation, we obtained 88% performance for real images, and showed that it can be used efficiently for representing the binary images. Also we cu make RCSD parameters to be the normalized patterns to have an invariant of its scale or position, and expand them to improve the quality of the performance.

• The Journal of the Korea Contents Association
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• v.6 no.2
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• pp.17-26
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• 2006

SIP(Session Initiation Protocol)-based centralized conference service model has advantage of easiness in conference management and service as compared to other models. However when media server which is one of the components of conference server is included in the conference server, this model shows disadvantage of high server work load with increasing numbers of conferences and participants. In this paper, to improve this problem, we have suggested and implemented a new conference service model in which an UA(User Agent) who first make the conference acts as a media server instead of conventional conference server and, the conference server with conference event package takes only part of management of the conference and its participants. Therefore, many more conferences can be held and managed compared to the conventional centralized conference service model because load of the conference server decreases in our suggested model md, furthermore the participants needs only make SIP call connections to the UA who first make the conference for establishing media session.

• Journal of the Korean Society for information Management
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• v.20 no.1
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• pp.301-320
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• 2003

The rapidly increasing use of the Internet and advancement of the communication network, the explosive growth of digital contents from personal home pages to professional information service the emerging file exchange service and the development of hacking techniques . these are some of the trends contributing to the spread of illegal reproduction and distribution of digital contents, thus threatening the exclusive copyrights of the creative works that should be legally protected Accordingly, there is urgent need for a digital copyright management system designed to provide centralized management while playing the role of bridge between the copyright owners and users for smooth trading of the rights to digital contents, reliable billing, security measures, and monitoring of illegal use. Therefore, in this study, I examined the requirements of laws and systems for the introduction of the centralized management system to support smooth distribution of digital contents, and also researched on the current status of domestic and international centralized management system for copyrights. Furthermore, 1 tried to provide basic materials for the standardization of digital contents copyright management information through the examination of the essential elements of the centralized digital contents management such as the system for unique identification the standardization for data elements, and the digital rights management (DHM) .

• Journal of the Institute of Convergence Signal Processing
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• v.7 no.1
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• pp.33-37
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• 2006

In this paper, we present a centralized monitoring system for infant incubator using Bluetooth. Conventional monitoring systems for incubators require large space and wire connection, which causes the spatial restrictions. To overcome this disadvantage, centralized monitoring system is proposed for infant incubators using Bluetooth. The implemented system consists mainly of transmission systems and receiver systems. There are temperature sensors, humidity sensors, ECG measurement units and Bluetooth modules in the transmission systems. For temperature, humidity and ECG data, the transmission systems acquire them from the measuring modules in the incubator and transmits the signals using Bluetooth. In the receiver system, users can see the status of the infant by accessing the central monitoring host computer. That is, one can monitor the information on the temperature and the humidity in the incubator and Infant's ECG without dependence to a conventional bulky system. Also, the system manager in the receiver system can maintain centralized monitoring of the situations in all incubators and infant. The developed system will be useful in remote diagnosis of infant incubator In various environments.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.4
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• pp.99-105
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• 2011

This paper presents a method to design a centralized repetitive controller that is robust to variations in the multiple system parameters. The uncertain parameters are specified probabilistically by their probability distribution functions. Instead of working with the distribution functions directly, the centralized repetitive controller is designed from a set of models that are generated from the specified probability functions. With this multiple-model design approach, any number of uncertain parameters that follow any type of distribution functions can be treated. Furthermore, the controller is derived by minimizing a frequency-domain based cost function that produces monotonic convergence of the tracking error as a function of repetition number. Numerical illustrations show how the proposed multiple-model design method produces a repetitive controller that is significantly more robust than an optimal repetitive controller designed from a single nominal model of the multiple system.

• Journal of Communications and Networks
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• v.14 no.2
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• pp.188-194
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• 2012

Cognitive networks (CNs) are capable of enabling dynamic spectrum allocation, and thus constitute a promising technology for future wireless communication. Whereas, the implementation of CN will lead to the requirement of an increased energy-arrival rate, which is a significant parameter in energy harvesting design of a cognitive user (CU) device. A well-designed spectrum-sensing scheme will lower the energy-arrival rate that is required and enable CNs to self-sustain, which will also help alleviate global warming. In this paper, spectrum sensing in a multi-user cognitive ad hoc network with a wide-band spectrum is considered. Based on the prospective spectrum sensing, we classify CN operation into two modes: Distributed and centralized. In a distributed network, each CU conducts spectrum sensing for its own data transmission, while in a centralized network, there is only one cognitive cluster header which performs spectrum sensing and broadcasts its sensing results to other CUs. Thus, a wide-band spectrum that is divided into multiple sub-channels can be sensed simultaneously in a distributed manner or sequentially in a centralized manner. We consider the energy consumption for spectrum sensing only of an analog-to-digital convertor (ADC). By formulating energy consumption for spectrum sensing in terms of the sub-channel sampling rate and whole-band sensing time, the sampling rate and whole-band sensing time that are optimal for minimizing the total energy consumption within sensing reliability constraints are obtained. A power dissipation model of an ADC, which plays an important role in formulating the energy efficiency problem, is presented. Using AD9051 as an ADC example, our numerical results show that the optimal sensing parameters will achieve a reduction in the energy-arrival rate of up to 97.7% and 50% in a distributed and a centralized network, respectively, when comparing the optimal and worst-case energy consumption for given system settings.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.171-174
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• 2006

A large number of service providers in countries all over the world have established GNSS reference station networks in the last years and are using network software today to provide a correction stream to the user as a routine service. In current GNSS network processing, all the geometric related information such as ionospheric free carrier phase ambiguities from all stations and satellites, tropospheric effects, orbit errors, receiver and satellite clock errors are estimated in one centralized Kalman filter. Although this approach provides an optimal solution to the estimation problem, however, the processing time increases cubically with the number of reference stations in the network. Until now one single Personal Computer with Pentium 3.06 GHz CPU can only process data from a network consisting of no more than 50 stations in real time. In order to process data for larger networks in real time and to lower the computational load, a federated filter approach can be considered. The main benefit of this approach is that each local filter runs with reduced number of states and the computation time for the whole system increases only linearly with the number of local sensors, thus significantly reduces the computational load compared to the centralized filter approach. This paper presents the technical aspect and performance analysis of the federated filter approach. Test results show that for a network of 100 reference stations, with the centralized approach, the network processing including ionospheric modeling and network ambiguity fixing needs approximately 60 hours to process 24 hours network data in a 3.06 GHz computer, which means it is impossible to run this network in real time. With the federated filter approach, only less than 1 hour is needed, 66 times faster than the centralized filter approach. The availability and reliability of network processing remain at the same high level.

• Nuclear Engineering and Technology
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• v.45 no.4
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• pp.427-438
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• 2013

In this paper we discuss spent fuel management options in the Republic of Korea (ROK) from two interrelated perspectives: Centralized dry cask storage and spent fuel pyroprocessing and burning in sodium fast reactors (SFRs). We argue that the ROK will run out of space for at-reactors spent fuel storage by about the year 2030 and will thus need to transition centralized dry cask storage. Pyroprocessing plant capacity, even if approved and successfully licensed and constructed by that time, will not suffice to handle all the spent fuel discharged annually. Hence centralized dry cask storage will be required even if the pyroprocessing option is successfully developed by 2030. Pyroprocessing is but an enabling technology on the path leading to fissile material recycling and burning in future SFRs. In this regard we discuss two SFR options under development in the U.S.: the Super Prism and the Travelling Wave Reactor (TWR). We note that the U.S. is further along in reactor development than the ROK. The ROK though has acquired more experience, recently in investigating fuel recycling options for SFRs. We thus call for two complementary joint R&D project to be conducted by U.S. and ROK scientists. One leading to the development of a demonstration centralized away-fromreactors spent fuel storage facility. The other involve further R&D on a combined SFR-fuel cycle complex based on the reactor and fuel cycle options discussed in the paper.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06d
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• pp.124-126
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• 2006

Mobile Ad hoc networking is an emerging technology and in these days many applications are being developed to run on these networks. In these networks lookup services are very important because all nodes do not have same resources in term of memory and computing power. Nodes need to use different services offered by different servers. Reliable and efficient scheme should be available for lookup services due to limited bandwidth and low computing power of devices in mobile ad hoc networks. Due to mobility and rapid change in network topology, lookup mechanism used in wired network is not appropriate. Service discovery mechanism can be divided into two main categories Centralized and Distributed. Centralized mechanism is not reliable as there is no central node in these networks. Secondly centralized mechanism leads toward single point failure. We can handle the service discovery mechanism by distributing server's information to each node. But this approach is also not appropriate due to limited bandwidth and rapid change in network. In this paper, we present reliable lookup service scheme which is based on distributed mechanism. We are not using replication approach as well due to low bandwidth of wireless networks. In this scheme service discovery mechanism will be handled through different lookup servers. Reliability is the key feature of our proposed scheme.

• Journal of the Korean Society for Library and Information Science
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• v.40 no.3
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• pp.11-34
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• 2006

A national library is a library specifically established and administrated by the government of a nation to serve as the repository of knowledge and information for that country. National libraries are generally a county's designated national repository, collecting literature Published in the country, in the language of the country, or about the country they represent. In case of advanced countries, national libraries have more than one branches at many different locations. Its system is called the distributed national library system. But the National Library of Korea maintains a centralized library system located in Seoul. This research which it tries to pay attention in this problem Point extracted a logical ground and suggested the mid-long term basic plan(S-shaved Branch Library Project) for a National Library of Korea to convert and reconstruct from centralized system to centralized-distributed system.