• Nuclear Engineering and Technology
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• v.35 no.2
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• pp.165-170
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• 2003

We developed an improved 3-PM liquid scintillation counting (3-PM LSC) method in which three detectors can be displaced to back and forth directions, and a data acquisition system being able to provide the values for all parameters required for the method. The detectors are entirely located in a 20-mm lead chamber of an inner diameter of 500 mm. A saw-toothed gear ties up all detectors so as to move them uniformly, up to 50 mm with unit of 1 mm. The data acquisition system was designed in an integrated circuit to perform the necessary works such as fast amplification, discrimination, coincidence and logic analysis. It generates values of nine parameters among twelve's generated in the 3-PH LSC method. The dead time of each counting channel is of extending type, valving from 10 to 100 $mutextrm{s}$. We measured the TDCR values with an unquenched liquid scintillation source 1"C by displacing the detectors with a step of 2.5 mm away from counting vial. Their values were derived on the range from 0.9 to 0.6. The extent is three times wider than those regions observed by applying the defocalization technique.ique.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.204-209
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• 2004

SiC materials have been extensively studied for high temperature components in advanced energy system and advanced gas turbine. However, the brittle characteristics of SiC such as low fracture toughness and low strain-to fracture still impose a severe limitation on practical applications of SiC materials. For these reasons, $SiC_f/SiC$ composites can be considered as a promising for various structural materials, because of their good fracture toughness compared with monolithic SiC ceramics. But, high temperature and pressure lead to the degradation of the reinforcing fiber during the hot pressing. Therefore, reduction of sintering temperature and pressure is key requirements for the fabrication of $SiC_f/SiC$ composites by hot pressing method. In the present work, Monolithic LPS-SiC was fabricated by hot pressing method in Ar atmosphere at 1760 $^{\circ}C$, 1780 $^{\circ}C$, 1800 $^{\circ}C$ and 1820 $^{\circ}C$ under 20 MPa using $Al_2O_3-Y_2O_3$ system as sintering additives in order to low sintering temperature. The starting powder was high purity ${\beta}-SiC$ nano-powder with an average particle size of 30 nm. Monolithic LPS-SiC was evaluated in terms of sintering density, micro-structure, flexural strength, elastic modulus and so on. Sintered density, flexural strength and elastic modulus of fabricated LPS-SiC increased with increasing the sintering temperature. In the micro-structure of this specimen, it was found that grain of sintered body was grown from 30 nm to 200 nm.

• Proceedings of the Safety Management and Science Conference
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• 2006.11a
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• pp.415-426
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• 2006

Many technical and nontechnical issues hinder enterprise wide workflow management. The most significant technical issue is the inability to deal with the heterogeneity among users, workflow types, and WFMSs. Not all users demand the same workflow functionality, so user interfaces of different levels of sophistication are required. Because workflow types cannot always be fully predefined, they often need to be adjusted or extended during execution. Unlike relational database management systems, however, each WFMS often has differing workflow metamodels. This leads to incompatibility between WFMSs, making integration into an environment comprising many heterogeneous WFMSs a troublesome and sometimes impossible task. Current Workflow system consists mainly of Database system. It contains some problems like that the integration relationship among system processes cant be expressed properly. This research has been focused on two phases that should be considered in the Workflow system. First of all, the first phase is the analysis phase; one of its role is to figure out independent execution task unit(Workflow component). The second phase is design phase that provides with the framework to execute these task units actively. The Workflow component extraction method in the analysis phase uses a analysis method called C-C Net and, in the design phase, the architecture that makes the these Workflow component executed actively is provided. Through this research, each process is divided into a task unit and more effective Workflow system could be formed by executing these units actively. Current system layer calls task units, on the other hand, the Workflow system this research implemented provides with the architecture that places a layer between them that controls task units actively.

• The KIPS Transactions:PartC
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• v.12C no.3 s.99
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• pp.369-378
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• 2005

War simulation system is a virtual space that my tactical simulation exercise is held. The data used in this system are considered sensitive and needs to be protected. But suity vulnerabilities and possible security loopholes were not considered when designing the war game simulation system. So currently the systemis highly vulnerable against hackers and data leakages. This paper proposed a security system for war game simulation system based on considering the currently vulunerabilities and possible suity leakages. The proposed security system supports security patches. In this paper, we analyze vulunerabilities of the running environment of current system and we design and implement the security system that is consisted of three components : Authentication System, Encryption System and Network Security System. The security patches are safe and there are no negative effects on the system's performance. The patches are proved to be effective and very reliable towards solving the security vulnerabilities.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.1
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• pp.58-67
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• 1992

For removing $NO_x$ and $SO_x$ from the flue gases emitted from stationary sources, $V_2O_5-MoO_3/TiO_2$ catalysts were prepared by the conventional impregnation method (aqueous solution) and a sort of surface fixation method(nonaqueous solution) as reported excellent reproducibility catalysts. And these catalysts observed their catalytic activities as well as their surface properties. V-Mo-O oxide, prepared from nonaqueous solution of $VOCl_3$ and $Mo(CO)_6$ and aqeous solution method, was supported as amorphous state by XRD and SEM measurements. The infrared spectra of fresh and used catalysts showed that in used catalysts, V=O bands decreased and new bands of vanadium oxysulfate bands were very sensitive. So the catalysts prepared from nonaqueous solution may bring about the high activity. Results from catalytic activity measurements at 350$^\circ$C, in the presence of $SO_2, NO$ conversion was more increased than in absence of $SO_2$. As the $MoO_3$ was added to $V_2O_5/TiO_2 system, SO_2$ conversion increased. It found that from the results, $V_2O-5-MoO_3/TiO_2$ catalysts prepared from an nonaqueous solution may bring about the high activity for both the reaction of NO and $SO_2$ removal.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.06a
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• pp.163-165
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• 2014

In this paper, we propose a world's first programmable video processing platform for video quality enhancement of 8K ($7680{\times}4320$) UHD (Ultra High Definition) TV at 60 frames per second. To support huge computation and memory bandwidth of video quality enhancement for 8K resolution, the proposed platform has unique features like symmetric multi-cluster architecture for data partitioning, ring data-path between clusters to support data pipelining, on-the-fly processing architecture to reduce DDR bandwidth, flexible hardware to accelerating common kernel in video enhancement algorithms. In addition to those features, general programmability of SRP (Samsung reconfigurable processor) as main core of the proposed platform makes it possible to upgrade continuously video enhancement algorithm even after the platform is fixed. This ability is very important because algorithms for 8K DTV is under development. The proposed sub-system has been embedded into SoC (System on Chip) and new 8K UHD TV using the programmable SoC is expected at CES2015 for the first time in the world.

• Journal of Broadcast Engineering
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• v.20 no.6
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• pp.963-966
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• 2015

This paper introduces a programmable multi-format video decoder(MFD) to support HEVC(High Efficiency Video Coding) standard and for other video coding standards. The goal of the proposed MFD is the high-end FHD(Full High Definition) video decoder needed for a DTV(Digital Tele-Vision) SoC(System on Chip). The proposed platform consists of a hybrid architecture that is comprised of reconfigurable processors and flexible hardware accelerators to support the massive computational load and various kinds of video coding standards. The experimental results show that the proposed architecture is operating at a 300MHz clock that is capable of decoding HEVC bit-stream of FHD 30 frames per second.

• Journal of IKEEE
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• v.24 no.2
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• pp.502-506
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• 2020

With the development of autonomous driving technology, the importance of object recognition technology is increasing. Haze removal is required because the hazy weather reduces visibility and detectability in object recognition. However, the image from which the haze has been removed cannot properly reflect the unique color, and a detection error occurs. In this paper, we use CIE1931 color coordinate system to extend or reduce the color area to provide algorithms and hardware that reflect the colors of the real world. In addition, we will implement hardware capable of real-time processing in a 4K environment as the image media develops. This hardware was written in Verilog and implemented on the SoC verification board.

• Annual Conference of KIPS
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• 2000.04a
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• pp.1089-1094
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• 2000

소형 고성능 가전기기를 실현하기 위한 다기능 고집적의 실리콘화에 대응하기 위하여 반도체 업계는 SoC(System On a Chip) 설계, 반도체 지적 재산권인 IP(Intellectual Property)에 관한 연구를 두개의 핵심 연구 항목으로 설정하여 진행되어 왔다. 반도체 레이아웃 이식 자동화 시스템은 설계 재활용(Design Reuse), IP의 실용화와 확산을 위한 핵심 연구 과제 중의 하나로써, Time-To-Market 과 Time-To-Money 를 동시에 가능토록 하는 근간의 기술이 된다. 본 연구는 정확하고 고속의 IP내의 반도체 소자 인식 알고리즘, 그래프를 이용한 제한 조건의 구현과 해석, 향상된 컴팩션(Compaction) 알고리즘의 연구로 말미암아 기존의 연구 결과 대비 평균 20배의 속도 향상과 평균 41%의 메모리만을 사용함으로써 경쟁 기술 대비 월등한 우위를 보이고 있다. 이로써, 대형의 반도체 설계 도면의 처리를 가능하도록 하였으며, 반도체 IP의 응용성(flexibility)을 부여 함으로써, IP의 재활용의 기초 연구와 SoC 설계 확산에 지렛대 역할을 하는 연구가 되리라고 예측한다.

• Nuclear Engineering and Technology
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• v.50 no.8
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• pp.1298-1305
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• 2018

The use of System-on-Chip (SoC) solutions in the design of on-board data handling systems is an important step towards further miniaturization in space. However, the Total Ionizing Dose (TID) and Single Event Effects (SEE) characterization of these complex devices present new challenges that are either not fully addressed by current testing guidelines or may result in expensive, cumbersome test configurations. In this paper we report the test setups, procedures and results for TID testing of a SoC microcontroller both using standard $^{60}Co$ and low-energy protons beams. This paper specifically points out the differences in the test methodology and in the challenges between TID testing with proton beam and with the conventional gamma ray irradiation. New test setup and procedures are proposed which are capable of emulating typical mission conditions (clock, bias, software, reprogramming, etc.) while keeping the test setup as simple as possible at the same time.