• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.550-551
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• 2013

Large-area RF-driven ion source is being developed at Germany for the heating and current drive of ITER plasmas. Negative hydrogen (deuterium) ion sources are major components of neutral beam injection systems in future large-scale fusion experiments such as ITER and DEMO. RF ion sources for the production of positive hydrogen ions have been successfully developed at IPP (Max-Planck- Institute for Plasma Physics, Garching) for ASDEX-U and W7-AS neutral beam injection (NBI) systems. In recent, the first NBI system (NBI-1) has been developed successfully for the KSTAR. The first and second long-pulse ion sources (LPIS-1 and LPIS-2) of NBI-1 system consist of a magnetic bucket plasma generator with multi-pole cusp fields, filament heating structure, and a set of tetrode accelerators with circular apertures. There is a development plan of large-area RF ion source at KAERI to extract the positive ions, which can be used for the second NBI (NBI-2) system of KSTAR, and to extract the negative ions for future fusion devices such as ITER and K-DEMO. The large-area RF ion source consists of a driver region, including a helical antenna (6-turn copper tube with an outer diameter of 6 mm) and a discharge chamber (ceramic and/or quartz tubes with an inner diameter of 200 mm, a height of 150 mm, and a thickness of 8 mm), and an expansion region (magnetic bucket of prototype LPIS in the KAERI). RF power can be transferred up to 10 kW with a fixed frequency of 2 MHz through a matching circuit (auto- and manual-matching apparatus). Argon gas is commonly injected to the initial ignition of RF plasma discharge, and then hydrogen gas instead of argon gas is finally injected for the RF plasma sustainment. The uniformities of plasma density and electron temperature at the lowest area of expansion region (a distance of 300 mm from the driver region) are measured by using two electrostatic probes in the directions of short- and long-dimension of expansion region.

• Journal of Sensor Science and Technology
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• v.25 no.4
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• pp.297-301
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• 2016

ISO/IEC JTC1/SC29WG11 MPEG has been standardizing UD(user description) to give a user personalized recommendation services. Besides, CD(context description), service description(SD), and recommendation description(RD) are recently being standardized by UD Adhoc Group in MPEG with an advanced UD to cope with needs of current and upcoming services such as augmented reality and social network. The descriptions was reflected to MPEG-UD WD(Working Draft) at MPEG $107^{th}$ meeting and the document was finally approved as international standard by national bodies with standard number(ISO/IEC IS 21000-22 UD) at $114^{th}$ MPEG meeting. In addition, reference software WD to validate conformance of UD standard was approved at $113^{th}$ MPEG meeting. In this paper, we developed a demo program for visual communication according to guideline defined in reference software WD to validate the reference software as well as UD standard.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.241.1-241.1
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• 2014

The large-area high-power radio-frequency (RF) driven ion sources based on the negative hydrogen (deuterium) ion beam extraction are the major components of neutral beam injection (NBI) systems in future large-scale fusion devices such as an ITER and DEMO. Positive hydrogen (deuterium) RF ion sources were the major components of the second NBI system on ASDEX-U tokamak. A test large-area high-power RF ion source (LAHP-RaFIS) has been developed for steady-state operation at the Korea Atomic Energy Research Institute (KAERI) to extract the positive ions, which can be used for the NBI heating and current drive systems in the present fusion devices, and to extract the negative ions for negative ion-based plasma heating and for future fusion devices such as a Fusion Neutron Source and Korea-DEMO. The test RF ion source consists of a driver region, including a helical antenna and a discharge chamber, and an expansion region. RF power can be transferred at up to 10 kW with a fixed frequency of 2 MHz through an optimized RF matching system. An actively water-cooled Faraday shield is located inside the driver region of the ion source for the stable and steady-state operations of RF discharge. The characteristics and uniformities of the plasma parameter in the RF ion source were measured at the lowest area of the expansion bucket using two RF-compensated electrostatic probes along the direction of the short- and long-dimensions of the expansion region. The plasma parameters in the expansion region were characterized by the variation of loaded RF power (voltage) and filling gas pressure.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.4
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• pp.254-259
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• 2014

In this paper, we describe construction of a wind stabilization demo-site and effects of output power control of wind turbines for suppression of ramp rate using ESS (Energy Storage System). It is difficult to control the output power of distributed generator such as wind turbine which of variation is very large. If the large capacity wind farm be interconnected into power system may cause blackout due to Power Quality. For these reasons, the international standards such as Grid-Code is limited to less than 10 [%/min] of renewable energy ramp rate. The case of Korea, government actively conducts propagating large-scale renewable energy for green growth policy, to interconnecting more renewable energy into power system is necessary for stabilization technology. For these reasons, the POSCO consortium has constructed a wind stabilization demo-site that is configured as 500 [kWh] battery energy storage systems can output up to 3 [C-Rate] and two wind turbines rated 750 [kW]. In POSCO consortium, which implements various methods stabilizing output power of wind turbine such as smoothing, section firming and ramp control, we derive the results of long-term demonstration that can be controlled to satisfy to the international standard about ramp rate [%/kW] of wind turbine output power.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.43-45
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• 2009

In case of favourable irradiation conditions, the ratio of irradiation to the total irradiation went up and then the irradiation increased in the area with high angle of inclination. The study showed that on a clear day with the irradiation of more than 80$[W/m^2]$, the pattern of alternating current power change in the fixed system was similar with that in the single-axis tracker. On the contrary, in case of unfavourable irradiation conditions, the ratio of diffuse irradiation to the total irradiation went up and then the horizontal irradiation increased. In the demo system, the fixed system, the single-axis tracker and the dual-axis tracker all had low generation power and similar generation pattern with each other. The study showed the generation power varied with the irradiation in the fixed system, while in the single-axis tracker and the dual-axis tracker, the amount of the generation Power variation was much more than the irradiation variation. The demo system was operated from 11:00 AM to 2:00 PM for generating power, during which time, 46[%] to 56[%] of the total generation power was produced. In this study, the generation power was increased by 147[%] in the fixed system, by 136[%] in the single-axis tracker, and by 164[%] in the dual-axis tracker, and the pattern of generation power was similar with the generation power variation in the situation where the irradiation increased by 140[%] in the spring with plenty of insolation. The alternating current power was more sensitive to variation of the irradiation than to that of the surface temperature of a module. The variation of the irradiation had a more positive effect on the generation power than the type of array.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.220-220
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• 2009

In case of favourable irradiation conditions, the ratio of irradiation to the total irradiation went up and then the irradiation increased in the area with high angle of inclination. The study showed that on a clear day with the irradiation of more than $800[W/m^2]$, the pattern of alternating current power change in the fixed system was similar with that in the single-axis tracker. On the contrary, in case of unfavourable irradiation conditions, the ratio of diffuse irradiation to the total irradiation went up and then the horizontal irradiation increased. In the demo system, the fixed system, the single-axis tracker and the dual-axis tracker all had low generation power and similar generation pattern with each other. The study showed the generation power varied with the irradiation in the fixed system, while in the single-axis tracker and the dual-axis tracker, the amount of the generation power variation was much more than the irradiation variation. The demo system was operated from 11:00 AM to 2:00 PM for generating power, during which time, 46[%] to 56[%] of the total generation power was produced. In this study. the generation power was increased by 147[%] in the fixed system, by 136[%] in the single-axis tracker, and by 164[%] in the dual-axis tracker, and the pattern of generation power was similar with the generation power variation in the situation where the irradiation increased by 140[%] in the spring with plenty of insolation. The alternating current power was more sensitive to variation of the irradiation than to that of the surface temperature of a module. The variation of the irradiation had a more positive effect on the generation power than the type of array.

• Environmental Engineering Research
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• v.18 no.2
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• pp.103-108
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• 2013

Vietnam is a developing country with the rate around 5%-6% per year, especially in urban areas. Rapidly developed urban areas lead to stress for infrastructure and the water supply is also stressed. In Hanoi city, total water capacity from the manufactories is around one million cubic meters per day and almost the entire main water source is groundwater but it is not enough to supply all of Hanoi's people, especially in the summer. A demo project is implemented in Hanoi University of Civil Engineering (HUCE) to produce drinking water by using the rainwater and membrane system and supply for people. In this project, rainwater is collected on the rooftop of the lecture building with an area of around $500m^2$ and $100m^3$ volumetric rainwater tanks. Afterwards, the rainwater is treated by the micro-membrane system and supplied to the tap water. Total cost for construction, technology and operation in the first year is around USD 48,558. In the long-term (15 yr) if HUCE invests in the same system, with $20m^3$ volumetric storage tank, it can provide drinking water for 500 staffs in every year. The cost of investment and operation for this system is lower than 30% compared to buying bottled water with the price USD 1.8/bottle. The drinking water parameters after treatment are pH, 7.3-7.75; turbidity, 0.6-0.8 NUT; total dissolved solids, 60-89 mg/L; coliform, 0; heavy metal similar with water quality in the bottle water in Vietnam.

• Journal of the Korea Society of Computer and Information
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• v.18 no.5
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• pp.9-17
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• 2013

This paper presents the design of the educational router system. This system is designed and implemented to support network configuration and embedded programming technology of the user on Internet. Not only Static routing protocol but also a kind of dynamic routing protocols such as OSPF and RIP and firewall have been programmed for education based on ethernet interface. ADS 1.2 as debugging environment, uC/OS-ii as RTOS and C language as development language are used. The educational procedures is compile, loading of static routing protocol, a kind of dynamic routing protocols such as OSPF and RIP and firewall program already supplied. Thereafter the verification is checked by using "ping" test to allow for demo operation such as hands-on training procedure. Finally programming procedure similar with demo operation of static routing protocol, a kind of dynamic routing protocols such as OSPF and RIP and packet filtering function is educated step by step.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.10
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• pp.125-154
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• 2004

Diesel Beitrag befasst sich mil der Sprache in gesellschaftlichen Umbruchssituationen aus der Perspektive einer spezifisch linguistischen Fragestellung. Im Zentrum der Untersuchung steht der Wandel der Sprachverwendung unter den Bedingungen der Demokratisierung der DDR und der Vereinigung mil der BRD seit der Wende 1989/90. Dieser Wandel wird am Beispiel der Lexik, und anhand von Losungen bzw. Demo-Spruchen konkretisiert. Im Zuge der 'Wende' sind $f\"{u}r$ beide Kommunikationsgemeinschaften - $\"{u}berwiegend$ aber $f\"{u}r$ die der neuen $Bundesl\"{a}nder$ - Neologismen in Gebrauch gekommen. Am bekanntesten sind: 'Mauerspecht', 'Wendehals', 'Moniagsdemo' und 'Stasi-Akte' usw. Andererseits wurden im Verlauf der Wende zahireiche Bezeichnungen, insbesondere $f\"{u}r$ $aufgel\"{o}ste$ Institutionen der DDR sowie viele verwaltungsspezifische $W\"{o}lfer$, historisiert. An Textbeispielen der Losungen des Herbstes 1989 werden uns die Dynamik sprachlicher Strukturen auf der einen Seite und die sich verandernden gesellschaftlichen $Verh\"{a}ltnisse$ in der $\"{o}ffentlichen$ Kommunikation der ehemaligen DDR auf der anderen Seite vol Augen gefuhrt. Verglichen mit den zum 1. Mai bekannt gegebenen of nziellen SED-Losungen, sind die Aktanten der Demo-Spruche das Volk, teils als Individuen und teils als spontan gebildete Gruppen. Im Unterschied zu den 'allen' offiziellen Losungen $repr\"{a}sentieren$ die Demo-$Spr\"{u}che$ verschiedenartige Sprechhandlungstypen: Nicht nur AUFFORDERN, APPELLIEREN, BEHAUPTEN, sondern auch FRAGEN, BESCHIMPFEN, DROHEN, $GR\"{U}{\ss}EN$usw. Gleichzeitig $\"{u}bernehmen$ sie viele Textmuster als sprachliche Stilmittel aus fem Bereich anderer Spruch- und Kurztextgattungen, wie zum Beispiel Sprichwort, Kinderreim, Aphorismus, Anspielung und verwenden auch Zitate. Auf diese Weise linden sich in den Wende-Losungen zahlreiche Belege $f\"{u}r$ intertextuelle $Bez\"{u}ge$. So schaffen diese Losungen $schlie{\ss}lich$ eine neue Qualitat des $\"{o}ffentlich-politischen$ Diskurses in der Gesellschaft. Am Rande der Untersuchungen haben wir $f\"{u}r$ das Deutsch in Ost und West festgestellt: $Bem\"{u}hungen$ der $Ann\"{a}herung$ und des sprachlich-kornrnunikativen Ausgleichs findet man seit der Wende 1989/90 eher auf der Seite der Ostdeutschen. Die sprachlichen Differenzierungen zwischen Ost- und Westdeutschland waren vornehmlich lexikalischer An. Es ist aber anzunehmen, dass es heute weniger die Sprache selbst ist als vielmehr das unterschiedliche Kommunikationsverhalten zwischen Ost- und Westdeutschen, das die Verstandigung zwischen Ost- und Westdeutschen schwierig zu machen scheint.

• School Mathematics
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• v.17 no.2
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• pp.273-287
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• 2015

The purpose of this study was to obtain a deeper understanding of didactic processing in the class that unified with engineering by analyzing on the types of the teacher's instumental orchestration and schematizing it as an activity system. In order to do so, a qualitative study of a 5th grade class for math-gifted students in Y elementary school with ethnography was conducted. Interviews with the students were held and various document data were collected during the participational observation of the class. The collected qualitative data were gone through the analytical induction while the instrumental orchestration of Drijvers, Boon, Doorman, Reed, & Gravemeijer as well as the secondgeneration activity theory of Engestrom were using as the frame of conceptional reference. According to the result of this study, there exist 4 types, such as 'technical demo' 'link screen board', 'detection-exploring small group' and 'explain the screen and technical demo'.