• Journal of Institute of Control, Robotics and Systems
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• v.16 no.2
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• pp.188-193
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• 2010

With GPS being the primary navigation system, Loran use is in steep decline. However, according to the final report of vulnerability assessment of the transportation infrastructure relying on the global positioning system prepared by the John A. Volpe National Transportation Systems Center, there are current attempts to enhance and re-popularize Loran as a GPS backup system through the characteristic of the ground based low frequency navigation system. To advance the Loran system such as Loran-C modernization and eLoran development, research is definitely needed in the field of Loran-C receiver signal processing as well as Loran-C signal design and the technology of a receiver. We have developed a set of Matlab tools, which implement a software Loran-C receiver that performs the receiver's position determination through the following procedure. The procedure consists of receiving the Loran-C signal, cycle selection, calculation of the TDOA and range, and receiver's position determination through the Least Square Method. We experiences the effect of an incorrect cycle selection and various error factors (ECD, ASF, sky wave, CRI, etc.) from the result of the Loran-C signal processing. It is apparent that researches which focus on the elimination and mitigation of various error factors need to be investigated on a software Loran-C receiver. These aspects will be explored in further work through the method such as PLL and Kalman filtering.

• Journal of Arbitration Studies
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• v.23 no.4
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• pp.139-167
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• 2013

Mediation, which is part of ADR, is a method used to settle disputes amicably by employing a third party who is in a neutral position. Utilization and attention on meditation are increasing in place of litigation and arbitration owing to its effectiveness in terms of time, cost, and effectiveness in achieving an amicable settlement. As to Korea, mediation at the civil level was employed by the KCAB in July 2012 but its utilization was in ABC stage compared to mediation at the governmental and judicial levels. Based on this situation, this study reviewed the guideline and system of the KCAB through a comparison of the management system between the KCAB and AAA where mediation was in good use. This study further suggests solutions as to the development of an international commercial mediation system First, the KCAB rule is needed to create a mediation language, mediation place, mediator internationalization, and so on. Second, a system backup is necessary to ensure the enforceability and effectiveness of mediation. Third, a unified mediation law in Korea is desirable for the harmonization of mediations at civil, governmental, and judicial levels. The unified mediation law, if it is made, may lead to an international base where this requirement exists. Fourth, advertising the merits of mediation to the public is necessary. Fifth, securing specialized mediators and relevant training are essential. If the above requirements are implemented, Korea would advance in international commercial disputes.

• Management & Information Systems Review
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• v.7
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• pp.317-340
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• 2001

The Busan shoe industry has been the accelerating overseas transfer of production facilities due to loss of competitiveness in the wake of drastic revaluation of the won, an increase in personnel expenses and the rise of backup developing countries since the late 1980s. On account of changes in the general system of supply and demand caused by a decrease in exports and production, the Industrial structure has been subjected to a transition from export to domestic demand. As a result, the Busan shoe industry, which used to rank second in the world in terms of its shoe export and to account for 16.5% in terms of its market share, started to be regarded as a fast-fading industry. As a domestic companies have a tendency to almost all the tasks on bloc, it is true that their competitiveness is on the rapid decline for they prefer self-reliance on the premise that all the production should be dealt with for themselves. It is outsourcing that is taken into account as a strategic vehicle for converting such self-reliance into the system of low expenditure and high efficiency.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.221.1-221.1
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• 2012

The Korea Astronomy and Space Science Institute (KASI) is developing three 1.6m optical telescopes with $18k{\times}18k$ mosaic CCD cameras. These telescopes will be installed and operated at Chile, South Africa, and Australia for Korea Micro-lensing Telescope Network (KMTNet) project. The main scientific goal of the project is to discover earth-like extra-solar planets using the gravitational micro-lensing technique. To achieve the goal, each telescope at three sites will continuously monitor the specific region of Galactic bulge with 2.5 minute cadence for five years. Assuming 12 hour observation in maximum for a night, the amount of 200 GB file storage is required for one night observation at one observatory. If we consider the whole project period and the data processing procedure, a few PB class data storage, high-speed network, and high performance computers are essential. In this presentation, we introduce the KMTNet data management plan that handles gigantic data; raw image collecting, image processing, photometry pipeline, database archiving, and backup.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.3
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• pp.279-286
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• 2006

The present study concerns the annual performance evaluation of a hybrid-renewable energy system with geothermal and solar heat sources for hot water, heating and cooling of the residential buildings. The hybrid energy system consists of ground source heat pump of 2 RT for cooling, solar collectors of $4.8m^2$, storage tank of 250 liters and gas fired backup boiler of 11.6 kW. The averaged coefficients of performance of geothermal heat pump system during cooling and heating seasons are measured as 4.1 and 3.5, respectively. Also solar fraction for hot water is measured as 35 percent. Overall, the results shows that the hybrid-renewable energy system satisfactorily operated under all climatic conditions.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.12
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• pp.799-804
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• 2011

Radioactivity of high concentrations have existed in the handling nuclear materials in hot cell of PIEF(Post Irradiation Examination Facility). The exhaust filtration system was enabled to process cylindrical filters by using a manipulator in the hot cell. By establishing a double filtration system with two filters, backup protection against leakage or failure of the first is provided by the second filter. Additionally, this a arrangement is arrange intended to increase the total filtration efficiency. The result of the pressure drop changing in the air flow of the cylindrical and HEPA filters is observed by a curved line. A filtering efficiency of more than 99.99% to $0.3{\mu}m$ particle appears in the upstream and downstream during the efficiency test on the HEPA filters. The V-pleats type had a lower pressure drop than the separator type. There was no damage during usage and was found to be suitable with high capacity of air volume. Therefore, by carrying out performance tests of the exhaust filtration system, efficiency and safety can be achieved.

• Journal of the military operations research society of Korea
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• v.28 no.1
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• pp.115-135
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• 2002

The limits of current DN(Defense networks), private and closed network, become to reality; for Example, high expense of construction and maintenance of networks, restriction of new subscribers on DN. Therefore, a network using web environment that reflect fast development of If and IS(Information Security) technology is demanded for MND. Meeting the requirement of reliable IS system and extension and improvement of DN using common network, we can reduce the expense to extend, maintain, repair DN, form the environment that makes military business cooperate better with civil company and government agency, advance implementing Defense computing and networking service for field small size units that was a exception of Defense digitalization. But it is essential to construct DN based on common network that there are security requisites; confidentiality, integrity, availability, efficiency, log, backup, restoration, that have to be realized at demanding level for IS. This thesis suggested four measurements; replacement DN with common network to resolve the requirements of building new network and improvement of performance for private DN, linkage with common network for new requirement, distribution of traffic using common network, configuration of DN using Internet and Proposed a refinement of IS management organization to treat security threat of common network flexibly, and LAN IS standard model of DN based on the web environment.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.682-684
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• 2003

With the explosive rapid expansion of computer using during the past few years, security has become a crucial issue for modem computer systems. Today, there are many intrusion detection systems (IDS) on the Internet. A variety of intrusion detection techniques and tools exist in the computer security community such as enterprise security management system (ESM) and system integrity checking tools. However, there is a potential problem involved with intrusion detection systems that are installed locally on the machines to be monitored. If the system being monitored is compromised, it is quite likely that the intruder will after the system logs and the intrusion logs while the intrusion remains undetected. In this project KIT-I, we adopt remote logging server (RLS) mechanism, which is used to backup the log files to the server. Taking into account security, we make use of the function of SSL of Java and certificate authority (CA) based key management. Furthermore, Support Vector Machine (SVM) is applied in our project to detect the intrusion activities.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.883-886
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• 1996

Instead of point-to-point hard wiring between substation yard equipments and SCADA RTU(Remote Terminal Unit), fibre optic cable will be used in the portion between Local Units and Central Unit in the future KEPCO 765kV substation. The connections between substation yard equipments and nearby Local Unit remain the same hard wiring. The new fibre optic system will provide security especially during ground faults and is immune to electrical noise. A prototype system will be manufactured and installed in the existing 154kV Yeosan Substation by the end of July this year and operated for one year. By incorporating the operation experiences acquired in the system, an improved system will be commercially applied to 765kV Shin-An-Seong Substation where 345kV GIS will be installed initially and act as the switching station in the year 1998. The system is composed of one Central Unit and several Local Units. The Central Unit is composed of two workstation level computers, one is in operation and the other backup, and a Communication Control Unit. The Local Unit uses the existing SCADA RTU technology and takes the form of a distributed one. Between the Communication Control Unit and Local Units, the fibre optic system with star-coupler is used.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.12
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• pp.1666-1672
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• 2015

Small islands are quite adequate places where microgrid system with renewable sources can replace diesel engines as operation costs of diesel engine in most small islands are very high. To get the large amount of renewable energy, the microgrid system has very large capacity of renewable sources. The system with large capacity of renewable sources can meet the case when supplied energy is greater than the load and the fluctuation of source output is very large. The battery energy storage system can be a solution to stabilize the system with large capacity of renewable sources. In this case, BESS can be utilized as a master source for the synchronous operation of all sources including diesel engine, wind turbine and PV. The diesel generators can be used as a backup in case the BESS SOC goes below a certain level. In this paper, we suggest a novel unit commitment of diesel generators and operation schedule of pump for water supply service with the information of wind forecast, PV forecast, and load forecast. The proposed methods has been implemented and tested at the test bed in Gasa-Island.