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The 30th International Conference on Plasma Science (ICOPS) which was held on Jeju Island, Korea, in June 2003, was the first effort by the IEEE Plasma Science and Applications Committee in its internalization to expand and strengthen the worldwide community. The February 2004 special issue of the journal "IEEE Transactions on Plasma Science" has published plenary and invited papers from ICOPS meetings. The topics of these articles ranged from basic plasma processes, microwave generation, and beam sources to newer research in fusion devices

The article offers information on 2011 International Symposium on Antennas and Propagation that is to be held at the Lotte Hotel Jeju, Korea from October 25-28, 2011 and also seeks submission of articles to be presented at the symposium.

The article presents several award recipients who were honored during the International Geoscience and Remote Sensing Symposium held on July 25, 2006 is Seoul, Korea. Richard Bamler was honored for his contributions to pattern recognition and data fusion in remote sensing. Gary G. Gimmestad of Georgia Institute of Technology for his contributions to atmospheric remote sensing technology. Furthermore, Kamal Sarabandi also received an award for his outstanding research related to remote sensing.

A 22.9 kV/50 MVA class high-temperature superconducting (HTS) power cable system was developed in Korea. For the optimization of electrical insulation design for HTS cable, it is necessary to investigate the ac and impulse breakdown and partial discharge inception stress of the liquid nitrogen (LN2)/laminated polypropylene paper (LPP) composite insulation system. These results were used to insulation design of the model cable for a 22.9 kV class HTS power cable and the model cable was manufactured. The insulation test of the manufactured model cable was evaluated in various conditions and was satisfied standard technical specification in Korea. Based on these experimental data, the single-phase and three-phase HTS cable of a prototype were manufactured and verified. [ABSTRACT FROM AUTHOR]

The article reports that the eleventh biennial IEEE Conference on Electromagnetic Field Computation was held in Seoul, Korea, from June 6-9, 2004. This conference attracted a larger number of papers than any previous conference, and the many high quality papers have proved that the conference remains one of the important forums for the scientific community working in computational electromagnetics.

The article offers information on the 8th Institute of Electrical and Electronics Engineers Inc.'s (IEEE's) Conference on Automation Science and Engineering (CASE) held in Seoul, Korea on August 20-24, 2012. It states that the 2012 conference recorded the highest number of paper submission and registrations in the history. Moreover, among the participants include the conference's organizer H. R. Choi, doctor Wonpil Yu, and Raj Madhavan.

The papers in this special section are extended versions of three selected papers from the IEEE Pacific Visualization Symposium 2012 (PacificVis) which took place in Songdo, Korea from 28 February to 2 March 2012. [ABSTRACT FROM AUTHOR]

The national standard of digital cable broadcasting in Korea as well as in North America has its root from the OpenCable and OpenCable Application Platform (OCAP). However, OCAP may have interoperability problems when an OpenCable-certified host is moved to a different service area where extended Application Programming Interfaces (API) not defined in the standard are used or code version management is not properly done between System Operators (SOs). Such abnormal cases can be easily found in practical business environments such as in merge and acquisition of SOs. Hosts used in two different SOs may use two incompatible OCAPs. In this paper, a new method is proposed to allow hosts to navigate in different SOs by modifying the Code Version Table (CVT) defined in the Common Download (CD) specification in OpenCable. Also, in this paper, actual validation of the idea using the modified CVT is included through several field tests. [ABSTRACT FROM AUTHOR]

Information about several papers discussed at the 2007 Asian Solid-State Circuits Conference (A-SSCC'07) at the Ramada PLaza Hotel in Korea on November 12-14 , 2007 is presented. It is said that the conference was sponsored by the IEEE Solid-State Circuits Society (SSCS), featuring achievements in the circuits design industry and technology application. A-SSCC'07 has a theme "The Blossoming of IC Design and Business in Asia."

A novel and fully automatic rigid fish cage system has recently been developed for deployment in the waters of Korea. The cage structure has 12 sides, incorporating a steel framework with a diameter and depth of 5.92 and 2.91 m, respectively. Attached to the steel framework is a housing for motor valves controlling variable ballast tanks, eight housings for two air compressors, a main control system, four batteries, a reserve air tank, four high air pressure tanks, 12 variable ballast tanks, and a seawater pump housing. The net of the fish cage is tightened across the frame to minimize volume reduction due to currents. The cage is outfitted with a control station located above the valve housing. With the control system, the buoyancy can be adjusted by utilizing compressed air stored in the four high air pressure tanks. The mechanical components of the ballast systems are operated by automated software that incorporates control and monitoring algorithms. The software initiates control of the ballasting components so the fish cage system can submerge if a preselected sea state occurs. The automatic control station incorporates a wind gauge, wireless communication printed circuit boards (PCBs), and a transmitting antenna. During operation, it monitors the wind speed, so the cage can be submerged before extreme sea states and then surfaced after the weather has passed and the conditions are considered safe. The control station also regulates the flow of air and seawater to and from the variable ballast tanks in response to the surface environmental conditions. Control can also be done remotely by a facility operator. In the development process, in situ tests were conducted to assess the performance of the submersion mechanism and the reliability of the automatic control system with a 1/4 size fish cage of similar construction. During the tests, the vertical position and inclination of the fish cage in the water column were measured. During the tests, the close/open states of the motor valves that control the 12 variable ballast tanks were also assessed during descent and ascent operations. The successful performance of the 1/4 size fish cage during the tests showed promise that such a system could possibly be used on a much larger scale to avoid the rigors of the environment in support of commercial level offshore aquaculture. [ABSTRACT FROM PUBLISHER]

This paper proposes automatic power changeover switch system applied superconducting fault current limiter (SFCL) of the Korea electric railway using 25 kV-AC Scott transformer. The electric railway needs neutral section to separate two different electrical power phase to m phase and t phase. While the train passes through the neutral section, the electrical power supply phase is changed over to other phase. And that time, the train must turn off the circuit breaker to avoid transient as ‘inrush-current’ and ‘arc’. These cause negative problems as speed decline of the train, a shorter life of the train circuit breaker. To improve the problems, the inrush current limitation method is proposed. In addition, we analysed the effect of proposed method using time-domain transient simulation software (PSCAD/ EMTDC). [ABSTRACT FROM PUBLISHER]

The subassembly procedure and relevant tools for the complete 40^\circ sector assembly as a foundation of the ITER machine have been developed to meet technical and functional requirements for years. Based on the concept of subassembly procedure and tools provided by ITER Organization, detailed procedure and relevant purpose-built assembly tools are developed by Korea Domestic Agency. The tools described in this paper contain an upending tool, a lifting tool, a sector subassembly tool, and a radial beam and vacuum vessel supports with alignment units. To verify the 6-degree-of-freedom system for fine alignment of components in the sector subassembly tool, scale-down mock-up has been manufactured and tested. This paper presents the overall 40^\circ sector subassembly procedure, the fundamental specifications of the relevant assembly tools, and the current status of the mock-up developments. [ABSTRACT FROM PUBLISHER]

In Korea, the KEPCO (Korea Electric Power Corporation) HTS power cable system has been successfully operated for evaluating the technical and economic feasibility as well as accumulating the operation experience since 2006. A cooling system composed of a liquid nitrogen decompression cooling unit and a closed-circulation system of subcooled liquid nitrogen at the KEPCO's Gochang power testing center. As the next step, we adjusted the cooling system for the purpose of testing a different cooling system using a cryocooler unit with cooling capacity of 4 kW at 77 K in the existing cooling system. It was designed to be used as a hybrid cooling system. In other words, it has as an each system of cryocooler unit or decompression pump unit. In this paper, the performance test results are summarized and the outline of the hybrid cooling system is introduced. [ABSTRACT FROM AUTHOR]

In Korea, the superconducting power cable has been developed since 2001, with the basic specifications of 22.9 kV/50 MVA. The superconducting power cable can carry more than 2 to 5 times higher electric power compared with conventional ones. It is important to test the DC critical current related with its power capacity before applying to the real power grid. In 1995, several international standards organizations including IEC, decided to unify the use of statistical terms related with "accuracy" or "precision" in their standards. It was decided to use the word "uncertainty" for all quantitative (associated with a number) statistical expressions. In this paper, we measured DC critical current of 22.9 kV/50 MVA superconducting power cable with several voltage tap and analyzed the uncertainty with these results. These analyzed results can be applied the standardization of the superconducting power cable [ABSTRACT FROM AUTHOR]

A 600 kJ HTS SMES system has been developed for power system stabilization as a national project in Korea. Successful operating tests of the 600 kJ were recently completed. In this paper, a 2.5 MJ class SMES with HTS magnets of single solenoid, multiple solenoid and modular toroid type were optimized using a recently developed multi-modal optimization technique named multi-grouped particle swarm optimization (MGPSO). The objective of the optimization was to minimize the total length of HTS superconductor wires satisfying some equality and inequality constraints. The stored energy and constraints were calculated using 3-D magnetic field analysis techniques and an automatic tetrahedral mesh generator. Optimized results were verified by 3D finite element method (FEM). [ABSTRACT FROM AUTHOR]

Research on resistive superconducting fault current limiters (SFCLs) using coated conductor(CC) has now been advanced from development to commercialization stage. It is necessary to investigate the recovery characteristics of SFCL for effective application to power system. In Korea, if the SFCL is directly inserted to distribution power grid, it must be recovered in 0.5 s after fault. Since temperature sensor is not accurate in liquid. nitrogen bathe and temperature of CC, after falling down below 92 K, is impossible to be measured by electrical method, it is difficult to measure the temperature of SFCL during the recovery of YBCO CC. In this paper, an experimental method was proposed to determine the recovery of resistive SFCLs. Under over-current for 0.1 s, maximum temperature of high temperature superconductor (HTS) wire increased to 300 K; after a few seconds, recovery time was measured by increasing DC current. With these experiments, thermal relaxation time required for the temperature of CC to decrease to 77 K was analyzed. [ABSTRACT FROM AUTHOR]

This paper deals with the preliminary study on the HTSC persistent current switch (PCS) for MAGLEV in Korea. The onboard HTSC levitation magnet system for high-speed maglev has advantage in power consumption because it can be operated in persistent current mode (PCM). The high speed superconducting maglev operated in PCM does not need the additional electrical energy to provide levitation force. To develop the PCS having good characteristics, it is important to develop a technology to minimize the joint resistance between two superconducting wires. The HTSC levitation magnet system consists of one HTSC magnet wound with Bi-2223 wire and a persistent current switch (PCS). The inductance of the magnet was 18.5 mH and total joint resistance of the magnet was 5.74 × 10-7 Ω. The PCS was experimented with respect to various ramping-up rates and magnitudes of charging current. The experimental results were compared with simulation results using finite different method. Based on these results, the current decay of 1 H class PCS using HTSC wire was calculated. [ABSTRACT FROM AUTHOR]

HTS transformers which have been developed until now had only fundamental structures. Among the auxiliary functions of conventional transformers, voltage regulating is the most important one. For the voltage regulation, conventional transformers are equipped with on load tap changers (OLTCs). In this paper, we investigate the possibility of the HTS transformer with OLTC. For the case study, we designed a single phase 33 MVA HTS transformer with OLTC. It is one of three individual HTS transformers which composes a 3 phase, 100 MVA transformer. It is expected to substitute for a 3 phase, 60 MVA conventional transformer in Korea. The parameters of an HTS transformer are varied due to the gap length between primary and secondary windings. The length was decided for the transformer to have the impedance of 12%. Its size was limited to the one of the conventional transformer. The characteristics of the HTS transformer were analysed in both case of having OLTC and not. [ABSTRACT FROM AUTHOR]

A superconducting fault current limiter (SFCL) using high temperature superconducting (HTS) wire has been developed in Korea. While the first-generation wire has difficulty in adopting various matrices because it is made by PIT process, the second-generation wire has flexibility in the design of its stabilizer. In general, coated conductor (CC) tape is clad with a thick metal layer as a stabilizer on the superconducting layer such as YBCO. In addition, the metal layer has good electrical conductivity. However, resistive SFCL, when a fault occurs, limits fault current using high resistance of the stabilizer. Therefore, the design of stabilizer is one of the most important parts in the design of SFCL. In this paper, over-current characteristics of CC tapes clad with stabilizers having various specifications were experimentally investigated. It was possible to design the stabilizer of CC based on calculation. An SFCL rated on 13.2 kV/630 A was designed using the optimal design of the stabilizer. [ABSTRACT FROM AUTHOR]

During the operation of a HTS power cable in a real grid, large fault current can be introduced to the HTS power cable by several accidents. Large heat is generated until the circuit breaker operates and severe performance degradation or even burn-out can occur within the HTS power cable. Especially, the temperature rise of the HTS power cable should be limited to suppress the bubble generation, which induces partial discharge and it reduces the life time of the HTS power cable. Stabilizer is applied to the cable core to limit the temperature rise when the fault current is introduced. This paper describes the fault current experiment with a sample cable and the results are used to verify the simplified analysis model. Through the analysis results, the amount of the stability is determined for the successful operation of Korean HTS power cable. [ABSTRACT FROM AUTHOR]

Current KEPCO's distribution automation system (DAS) provides a very effective restoration solution for the single fault case but cannot handle multiple faults. This paper proposes a two-step restoration scheme—sequential and simultaneous restoration--for multiple fault cases. Efficiency has been achieved by introduction of restoration performance index (RPI) and load-balancing algorithm. Test results to show effectiveness of the proposed scheme are presented, and field experience of DAS in Korea is described as well. [ABSTRACT FROM AUTHOR]

More than three HTS cable development and installation projects are proceeded over the world. A 22.9 kV/50 MVA class HTS cable system has been developed in Korea during last 3 years. And the HTS cable system for commercialization will be developed and installed on the real or test power grid within 2 years. Every HTS cable system has to satisfy the fault-current specifications of the power grid in order to protect the cable itself from the fault current. HTS cable composed of HTS tapes has some capacity of enduring the fault current by bypassing the fault-current through its Ag-sheath. But it may not be enough. So, some Cu stabilizer is generally introduced inside the conductor layers and outside the shield layers of HTS cable core for some higher fault current grade. In this paper, the design method of HTS cable with Cu stabilizer will be introduced. And the fault current capacity of HTS cable and its eddy current loss generated from the stabilizer will be calculated. And the impedance change of HTS cable in the fault current state will he calculated. [ABSTRACT FROM AUTHOR]

Several types of detectors such as ultraviolet (UV), infrared (IR), visible light (VL), different pressure, flame rod, and others are employed to detect a fire flame in power generation plants. However, these flame detectors have some performance problems. Therefore, this paper describes the image-processing method of fire detection as well as the neural-network modeling. Nowadays, the image-processing technique is broadly applied in the industrial fields. An extracted image information is taken into the inputs of the neural-network model. The neural-network model has strong adaptability and learning capability; therefore, this model can be suitable for pattern classification. The Ulsan Steam Power Generation Plant in Korea is employed as the test field. If this technique can be implemented in physical plants, the boilers can be operated economically and effectively. [ABSTRACT FROM AUTHOR]

This paper introduces T-DMB transmission system in Korea based on Eureka-147 DAB and presents a new architecture of transmission system for digital multimedia services. For transmission of the digital multimedia contents in mobile environment by using the existing DAB, we developed a T-DMB processor which performs T-DMB encoding and insertion of the media stream into the existing DAB transmission system. After the implemented T-DMB processor can be connected to the front of the commercial Eureka-147 DAB system, and the performance of the T-DMB system is confirmed through the T-DMB experimental broadcasting in Korea. [ABSTRACT FROM AUTHOR]

During the operation of the Korea Superconducting Tokamak Advanced Research (KSTAR), there exist various disturbances that cause the conductors to become unstable. The KSTAR Toroidal Magnet (TF) system was designed to secure the sufficient stability against them. The stability analysis showed that the energy margin of the TF Cable-In-Conduit (CIC) conductor was sufficiently high so that the expected disturbances could not cause the conductor to quench. During the 2nd KSTAR campaign in 2009, the cryogenic stability of the TF magnet system was analysed by energizing it up to 36 kA that is a bit higher than the designed current of 35.2 kA. The temperature increase measured at helium outlets was less than 0.1 K, which was well consistent with the analysis. Even in the reference plasma scenario, it was expected from the analysis that there still exists the sufficient temperature margin more than 4 K. The quench analysis was carried out to validate the design of the present TF CIC conductor from the magnet protection's point of view. In this paper, the cryogenic stability of the TF magnet system was estimated and the quench detection parameters were derived for protecting possible damages from quenches. [ABSTRACT FROM AUTHOR]

The Korea Superconducting Tokamak Advanced Research (KSTAR) adopted superconducting coils which consist of rectangular cable-in-conduit conductors (CICC) without a central hole for supercritical helium. Most of all, the KSTAR has a unique superconducting magnet system with Nb3Sn and NbTi such as ITER. We expect that the test results of KSTAR experiments can also provide useful information for ITER and the other fusion devices. Up to now, the KSTAR superconducting magnet system is showing a larger flexibility and reliability in operation. For example, the TF magnet system has achieved the current charging of 36.2 kA and PF magnet system has been also charged up to \pm4 kA without difficulties during the last two times KSTAR campaigns. The significant thermo-hydraulic characteristics such as helium flow distribution, pressure drop between the inlet and outlet of coil, the friction factor and the temperature variation according to the current charging operations are introduced in this paper. [ABSTRACT FROM AUTHOR]

In this paper, the authors present three-dimensional television (3DTV) broadcasting and distribution systems that are employed to deliver a pair of stereoscopic images to mobile users, as well as users at home. First, mobile 3DTV systems and services based on DMB and DVB-H are respectively introduced. Second, fixed and high-definition 3DTV systems and services based on terrestrial digital broadcasting are described along with an introduction of experimental 3DTV services in Korea. To be specific, the authors summarize 3DTV systems from the viewpoints of target services, system and user requirements, system configurations, broadcasting trials, related standards, and technical challenges. [ABSTRACT FROM AUTHOR]

A new ground-based 22-GHz radiometer, designed to deliver middle atmospheric water vapor profiles over the mid-latitudinal Asian continent, was designed at the University of Bern, Switzerland. In this paper, we outline the calibration and retrieval concepts of the instrument, which has been in operation in Seoul (37.32 ^\circ\ \N, 126.57^\circ\ \E), Korea, since November 2006. In addition, a quality assessment of the delivered profiles is presented, through the validation with the data from the Microwave Limb Sounder (MLS) onboard the Aura satellite. The differences between the Seoul Water Vapor Radiometer and Aura MLS are better than 2% between 1 and 0.2 hPa, and they decline nearly linearly to -14.5% between 0.2 and 0.01 hPa. [ABSTRACT FROM AUTHOR]

In this paper, a RF front-end of the 5.8 GHz integrated CMOS dedicated short range communication (DSRC) transceiver for the Korea/Japan electronic toll collection system is presented. The receiver uses low-IF conversion architecture for high sensitivity and low-power consumption while the transmitter uses direct up-conversion architecture for its simple structure and reliability. To solve image problem in the low-IF receiver, 10 MHz IF and 40 MHz IF are chosen for Korean and Japanese DSRC standards, respectively, since they make no image signals exist in image band. A single-quadrature mixer with the proposed transconductor-type quadrature generator in RF signal path is also adopted which has accurate quadrature characteristic in 5.8 GHz frequency. [ABSTRACT FROM PUBLISHER]

Enlarging the electric power supply capacity of 22.9 kV distribution line by upgrading the main transformer from 60 MVA to 100 MVA has been under consideration in order to cope with increasing electric power demands of distribution line in Korea which aims to replace some 154 kV supply demands by 22.9 kV large-capacity distribution systems. In this case, the prospective fault current of 22.9 kV distribution line is much bigger than the rated withstand fault current level of conventional electric equipments. As a major feasible solution to reduce excessive fault current, superconducting fault current limiters (SFCLs) are considered to be installed at 154 kV/22.9 kV substation. But until now, certified specifications or test procedures were not available considering utilities' requirements. And the performances of various types of SFCLs were not deeply investigated regarding the reclosing scheme of conventional networks. In this paper, in order to determine the suitable type of SFCL for newly installed 22.9 kV large distribution line in Korea, requirements and specifications of SFCLs were proposed considering the installation spots of large-capacity distribution line. Four types of SFCLs were modeled and analyzed using EMTP and their performances focusing on the coordination with reclosers were investigated to verify the suitability into the large-capacity distribution line. Consequently, detailed specifications and expected installation sites were proposed and suitable types of SFCLs for 22.9 kV large-capacity distribution line were suggested. [ABSTRACT FROM AUTHOR]

As high temperature superconducting (HTS) power cables have some merits over conventional cables, several demonstration projects on the HTS cable system are presently under way around the world. Korea Electric Power Corporation (KEPCO) also initiated an HTS cable project in 2002 with the Korean government's support. A three phase 100 m HTS cable system with a capacity of 50 MVA has been installed at Gochang test yard, located in Chonnbuk province, Korea. The HTS cable system is composed of a 100 m-long cable, two terminations and a cooling system. The rated current is 1,250 Arms and the rated voltage is 22.9 kV considering compatibility with the conventional power distribution system in Korea. Main purposes of this project are to verify the performance of an HTS cable system and to evaluate the potential of the HTS cable system from the viewpoint of power utilities. The real grid application of the HTS cable system requires the demonstration of system reliability, accumulated operation experiences, and it has to meet the practical needs of the utilities. In such a meaning, this project provides various challenges for KEPCO, and the feedback will be delivered to cable manufacturers. This user initiative test will facilitate the introduction of HTS cable systems into a real grid network. The installation process of the HTS cable system and some results of the preliminary test were presented in this paper. [ABSTRACT FROM AUTHOR]

A 100 MVA, commercial class high temperature superconducting (HTS) transformer was designed. In this paper the cryogenic system to extract the heat generated at the winding due to the AC loss and the heat penetration through the wall and the current lead and keep the winding temperature under design temperature is presented. The operation temperature is set at 67 K to increase the critical current and reduce the amount of HTS tape usage and the volume. The HTS winding was concentrically arranged to reduce the AC loss. The system consists of main cryostat with the windings and secondary cryostat with cooler, cryopump and the heat exchanger inside. The liquid nitrogen is entering the main cryostat at 65 K and assumed to be leaving at 67 K. The winding temperature distribution is simulated with the anticipated heat load using Fluent. The effect of the liquid nitrogen flow rate, inlet location is investigated and discussed. This work was supported by a grant from the Center for Applied Superconductivity Technology of the 21st Century Frontier R&D Program funded by the Ministry of Science and Technology, Republic of Korea. [ABSTRACT FROM AUTHOR]

This paper presents the field trial results of the terrestrial digital multimedia broadcasting (T-DMB) service in Korea. The T-DMB system, based on the Eureka-147 digital audio broadcasting (DAB) system, provides streaming video, CD-quality audio and data services at speeds of up to 300 km/h using H.264 video codec along with additional channel coding and interleaving schemes. In order to provide seamless high-quality services on various radio channels, we measured the bit error rate (BER), electric field strength (EFS), and subjective video quality using specially-designed mobile test equipment. From the field tests we obtained the required effective EFS (EEFS) for error-free reception and also derived the minimum EFS from the link budget analysis. Furthermore, we present the optimal transmit and receive parameters for constructing the T-DMB networks and also developing T-DMB broadcasting equipment and mobile receivers. [ABSTRACT FROM AUTHOR]

Commercial terrestrial digital multimedia broadcasting (T-DMB) service was launched on December 1st, 2005, in the Seoul metropolitan area of the Republic of Korea. As the world's first commercial terrestrial mobile multimedia broadcasting service, T-DMB garnered huge attention in the field of mobile broadcasting. This paper presents the history, system, and services of T-DMB. [ABSTRACT FROM AUTHOR]

In December 2005, Korea launched Terrestrial DMB (T-DMB) services for the first time in the world, making multimedia broadcasting services available in the mobile environment. In addition to high-quality digital radio (audio) and television (video), diverse data services, such as Traffic and Travel Information, BIFS, and Visual Radio, are currently being serviced. At the moment, there are no mobile/portable T-DMB terminals in the market that can support all the data services available. In this paper, we present a low-power portable T-DMB receiver, which can decode not only T-DMB video services but also various data services. In particular, it can simultaneously decode DMB video and data services within the same ensemble. [ABSTRACT FROM AUTHOR]

The article offers information on the 2011 International Symposium on Antennas and Propagation (ISAP 2011) to be held in Lotte Hotel Jeju, Korea on October 25-28, 2011.

The power demand is rapidly increasing in Korea, especially in the urban areas that include the metropolitan area. In addition, the transmission system in Korea is a network structure that ensures the high reliability and stability of power supply. Accordingly, the fault current rapidly increases in the case of a power system fault, due to the decrease in the line impedance. The superconducting fault current limiter (SFCL) was devised to address these existing problems refid="ref1"/refid="ref2"/refid="ref3"/ refid="ref4"/. [ABSTRACT FROM PUBLISHER]

In order to electrically investigate the AC losses of the conductor and the shield in an actual HTS cable with shield, we attached two voltage-leads to the conductor and shield of a short cable which is the same as the Korea Electric Power Corporation (KEPCO) HTS cable under the field test, and examined it. The result shows that the polarities of the loss voltages measured from both voltage-leads are opposite. The ratio (1.6) between the losses for different transport periods measured from the conductor-lead is quite large. It is considered from these results that the conductor loss is the sum of the losses measured from the conductor-lead and shield-lead. And this conductor loss corresponds well with the numerical result too. Moreover, the total loss of the short cable measured from the proposed electrical method at 77 K was compared with that of the KEPCO cable by calorimetry at 66.6 K through our numerical model. The difference between the measured losses and numerical ones is almost the same. This means that the shield loss is measured from the shield-lead, and the conductor loss from both voltage-leads. [ABSTRACT FROM AUTHOR]

As a way to improve performance of ITER TF conductors, two types of Nb3Sn cable-in-conduit conductors were developed in Korea with variations of conduit thickness resulting in the different void fraction of the conductors. The estimated void fractions of the conductors are 31% and 33%. Here we report the details of the TF conductor development and the performance test result of them carried out in SULTAN. Regarding the conductor development, the internal-Sn-processed Nb3 Sn strand characteristics, strand cabling, twist pitch and characteristics of the conduits for the conductors are presented. For an extended understanding of the conductor design and performance, the SULTAN test results are presented and the effect of the void fraction variations is discussed based on the results. [ABSTRACT FROM AUTHOR]

HTS transformers are being developed by one of 21st Century Frontier R&D Programs in Korea. The final target of the program for the HTS transformer is to develop a 3 phase 100 MVA HTS power transformer. Before then, we proposed a single phase 5 MVA HTS transformer using 2G wires. It is not for commercialization but for the preliminary research for fabricating the 100 MVA HTS transformer. We supposed volt per turn of 100. It has primary, secondary and tertiary windings. Its size is almost same with that of a 33 MVA single phase HTS transformer in previous work. AC losses due to the winding methods and the variations of other parameters are analysed. [ABSTRACT FROM AUTHOR]

Focuses on the 6th Asia Pacific Conference on Communications held in Seoul, Korea from October 30 to November 2, 2000. Topics discussed in the technical sessions; Information on the planned tutorials and mini-workshops; Speakers in the opening plenary.

Presents a study which examined the effects of the contextual factors on the implementation of the client/server system as an interrelated information technology innovation in Korean organizations. Methodology of the study; Results of the study; Conclusions.

Introduces the main service characteristics and overall architecture of the Korean high definition television (HDTV) broadcasting system. Purpose of developing the system; Overview of the link analysis for the HDTV broadcasting system; System requirement specification; Information about the overall system architecture.

The sixteenth International Symposium on Antennas and Propagation (ISAP2011) was held at the Lotte Hotel Jeju, Korea, from October 25 (Tuesday) to October 28 (Friday), 2011. This symposium was sponsored and organized by the Korean Institute of Electromagnetic Engineering and Science (KIEES), and cosponsored by the Communications Society of the Institute of Electronics, Information and Communication Engineers (IEICE). It was technically cosponsored by the Antennas and Propagation Society of the Institute of Electrical and Electronics Engineers (IEEE AP-S), the Antennas Society of the Chinese Institute of Electronics (CIE-AS), the International Union of Radio Science (URSI), the IEEE AP-S Seoul Chapter, and the Institute of Electronics Engineers of Korea (IEEK). [ABSTRACT FROM AUTHOR]

The Korea heat load test facility using electron beam (KoHLT-EB) was constructed and commissioned to perform high heat flux testing on plasma facing components (PFCs), such as ITER blanket first wall, the tungsten divertor, and heat transfer experiments on other cooling devices. Also it will be used for the thermo-hydraulic performance test of ITER helium cooled ceramic reflector test blanket module in Korea. Qualification tests will be performed to evaluate the use of the high heat flux test facility on PFC and fusion reactor materials. For the thermal fatigue test of PFCs, two types of tungsten mockups were fabricated. One is a coated tungsten on the ferritic–martensitic steel (FMS). The other is a hot isostatic pressing bonded tungsten with FMS. Also, the integrity and cooling performance should be tested under the same or similar operation conditions of the ITER PFCs. After the completion of the preliminary mockup test and the facility qualification, the high heat flux test facility, KoHLT-EB, will provide the performance test for the various PFCs in fusion reactor materials and PFCs. [ABSTRACT FROM PUBLISHER]

ITER first wall (FW) includes a beryllium armour joined to a Cu heat sink with a stainless steel back plate. These FW panels are one of the critical components in the ITER tokamak with a maximum surface heat flux of 5 MW/m2. Therefore, a qualification test needs to be performed with the goal to qualify the joining technologies required for the ITER FW. Various mock-ups were fabricated to develop the manufacturing procedure of FW components. For the nondestructive examination of the fabricated mock-ups, an ultrasonic test (UT) was performed with optimized probes. The UT was performed by using a three-axis digital ultrasonic C-scan system and software. The system comprised an ultrasonic pulser and receiver, model Panametrics 5800PR; a personal computer having an internal analog/digital converter board and four-axis motion control board; and a three-axis scanning tank. Two types of transducers were used for this experiment. One was Panametrics V312-SU, having a center frequency of 10 MHz (nominal) and a piezoelectric element diameter of 0.25 in with a flat protective layer for the Be/Cu. The other was Panametrics V309-SU with a center frequency of 5 MHz and an element diameter of 0.5 in for the Cu/SS interface. Winspect software controlled all aspects of data acquisition, motion control, data archiving, and image display. Based on the acceptance criteria, the average amplitude of the interface signals, which have about 50% of the reference echo amplitude, was recorded and analyzed on each beryllium tile. An image-analysis software analyzed the statistics of amplitude distribution and calculated the unacceptable area. Each mock-up that passed these UTs was concluded to qualify the joining technologies required for an ITER FW by using a high-heat flux test facility. As a result of these qualification tests based on the acceptance criteria of an ITER FW, the fabrication technologies will be utilized to develop the FW of plasma-facing components. [ABSTRACT FROM PUBLISHER]

A dual-band passive radio frequency identification (RFID) tag antenna applicable for a recessed cavity in metallic objects such as heavy equipment, vehicles, aircraft, and containers with long read range is proposed by using an artificial magnetic conductor (AMC) ground plane. The proposed tag antenna consists of a bowtie antenna and a recessed cavity with the AMC ground plane installed on the bottom side of the cavity. The AMC ground plane is utilized to provide dual-band operation at European (869.5\,\sim\,869.7 MHz) and Korean (910\,\sim\,914 MHz) passive UHF RFID bands by replacing the bottom side of the metallic cavity of a PEC-like behavior and, therefore, changing the reflection phase of the ground plane. It is worthwhile to mention that the European and the Korean UHF RFID bands are allocated very closely, and the frequency separation ratio between the two bands is just about 0.045, which is very small. It is demonstrated by experiment that the maximum reading distance of the proposed tag antenna with optimized dimensions can be improved more than 3.1 times at the two RFID bands compared to a commercial RFID tag. [ABSTRACT FROM PUBLISHER]

To develop a Korean (KO) test blanket module (TBM) for an International Thermonuclear Experimental Reactor (ITER), particularly for a liquid breeder type, a currently developed conventional code, CFX, with an electromagnetic module for analyzing the magnetohydrodynamics (MHD) effect of the liquid breeder under a high magnetic field is numerically validated using a theoretical equation and previous experimental data. From a comparison with the previous data, the code shows its capability to simulate the MHD effect very well. The KO TBM was then analyzed using the code for comparing the velocities and pressure drops when there was a high magnetic field of the ITER condition (5 T) and when there was not. From the analysis, the pressure drop increased from 0.008337 to 486.8 Pa, and the flow became more uniform in the upward region but concentrated in a corner or inlet manifold, which provided the idea to modify the manifold design. Since the pressure drop by the MHD effect will be tested with the constructed experimental loop for the liquid breeder, a preliminary analysis was performed using the installed test section and magnet, which can produce a magnetic field of up to 2.2 T. [ABSTRACT FROM PUBLISHER]

KSTAR is a fully superconducting tokamak in operation since 2008 at the National Fusion Research Institute in Korea. All coils are wound using cable-in-conduit conductors and cooled with forced-flow supercritical helium at 4.5 K and 5.5 bar. We consider here the central pair, PF1U/L, of the central solenoid coils; during operation, these coils are subjected to sharp current transients, which induce ac losses in the coil. The thermal hydraulic transient following a trapezoidal current pulse, with a ramp-up to 10 kA at a rate of 1 kA/s and a ramp-down to 0 kA at a rate of 10 kA/s, is simulated here using the 4C code, and the results are compared with the measurements. [ABSTRACT FROM PUBLISHER]