• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.10 no.1
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• pp.107-112
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• 2014

The Code of Federal Regulations, Title 10, Part 50, Appendix H requires surveillance program for reactor pressure vessel(RPV) that the peak neutron fluence at the end of the design life of the vessel will exceed $1.0E+17n/cm^2$ (E>1.0MeV). 2D/1D Synthesis method based on DORT 3.1 transport calculation code has been widely used to determine fast neutron(E>1.0MeV) fluence exposure to RPV in the beltline region. RAPTOR-M3G(RApid Parallel Transport Of Radiation-Multiple 3D Geometries) performing full 3D transport calculation was developed by Westinghouse and KRIST(Korea Reactor Integrity Surveillance Technology) and applied for the evaluations of In-Vessel and Ex-Vessel neutron dosimetry. The reaction rates from measurement and calculation were compared and the results show good agreements each other.

• Journal of Advanced Navigation Technology
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• v.14 no.6
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• pp.845-850
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• 2010

In this paper, a method for transmitting layered SVC streams in differentiated MBSFN channels is presented. Scalable coded video streams are transmitted in modulation channels of different efficiency that it achieves reduced resource consumption compared to non-scalable AVC stream. When utilizing with Raptor FEC, the combined effect is enhanced service coverage with providing minimum video quality at the edge of the service area, than the case of AVC.

• Journal of Communications and Networks
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• v.17 no.3
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• pp.221-230
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• 2015

Rateless codes have been shown to be able to provide greater flexibility and efficiency than fixed-rate codes for multicast applications. In the following, we optimize rateless codes for unequal error protection (UEP) for multimedia multicasting to a set of heterogeneous users. The proposed designs have the objectives of providing either guaranteed or best-effort quality of service (QoS). A randomly interleaved rateless encoder is proposed whereby users only need to decode symbols up to their own QoS level. The proposed coder is optimized based on measured transmission properties of standardized raptor codes over wireless channels. It is shown that a guaranteed QoS problem formulation can be transformed into a convex optimization problem, yielding a globally optimal solution. Numerical results demonstrate that the proposed optimized random interleaved UEP rateless coder's performance compares favorably with that of other recently proposed UEP rateless codes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.12C
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• pp.991-996
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• 2008

In this paper, we propose an LDPC-coded hybrid ARQ system using incremental redundancy and retransmission of a part of the transmitted packets. We also present a simple criterion for choosing two methods to support a desired throughput efficiently. Furthermore, we show that the throughput performance can be improved when multi-edge type LDPC codes with the structure of Raptor codes are employed for a hybrid ARQ scheme.

• Defense and Technology
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• no.8 s.222
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• pp.68-77
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• 1997

미 공군은 신형 전투기의 개발에서 초음속 순항능력, 긴 항속거리, 낮은 피탐지율, 신속한 기동성, 높은 신뢰도를 주요 설계 착안점으로 생각하고 90년대 후반에 작전 배치하여 21세기가 시작되는 시기에 미 공군의 일차적인 전투기로 활용하겠다는 생각을 가지고 있다.

• Aerospace Industry
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• v.53
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• pp.44-55
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• 1997

묘하게도 금년은 미공군 창설 50주년에 해당한다. 이를 기념하듯 금세기 최강의 전투기라는 별명을 가진 F-22가 4월초에 출고되었고 지상 시험을 거친 뒤 지난 5월말에는 마리에타 공장에서 첫비행에 성공했다. 여기서 10회 정도의 비행시험을 거친 뒤 에드워드 공군기지로 보내 제1호기로서 공식적인 비행시험을 실시하게 되어 있다.

• Defense and Technology
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• no.10 s.224
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• pp.68-75
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• 1997

F-22기는 지난 4월 9일 출고되어 전세계의 시선을 받은바 있으며 5월 최초의 시험비행을 하였다. 미 공군은 2010년까지 438대의 F-22 전투기를 구매하여 F-15기를 대체할 계획이었으나, 국방예산의 제약때문에 국방현대화 계획의 조정이 불가피할 것으로 보여 F-22기도 350대 이하로 감소될 가능성이 크다.

• Journal of Broadcast Engineering
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• v.25 no.4
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• pp.609-619
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• 2020

In accordance with a demand for high quality video streaming, it needs high data rate in limited bandwidth and more traffic congestion occurs. In particular, when providing real time video service, packet loss rate and bit error probability increase significantly. To solve these problems, a raptor code, which is one of FEC(Forward Error Correction) techniques, is pervasively used in the application layers as a method for improving real-time service quality. In this paper, we propose a method of determining image transmission parameters based on various deep neural networks to increase transmission efficiency at a similar level of image quality by using raptor codes. The proposed neural network uses the packet loss rate, video encoding rate and data rate as inputs, and outputs raptor FEC parameters and packet sizes. The results of the proposed method present that the throughput is 1.2% higher than that of the existing multimedia transmission technique by optimizing the transmission efficiency at a PSNR(Peak Signal-to-Noise Ratio) level similar to that of the existing technique.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.755-758
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• 1998

As the performance of microprocessor improves, the design complexity grows exponentially. Therefor, it is very important to make the bug-free model as early as possible in a design life-cycle. This paper describes the simulation-based functional verification methodology for the RTL level description model. It is performed by multi-stage verification methods using extensive hand-generated self-checking tests supplemented with random tests. This approach is opplied to the functional verification of the GPU processor of Raptor and various bugs are detected.

• Defense and Technology
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• no.9 s.259
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• pp.26-37
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• 2000

대부분의 나라들은 미래 항공력(Air Power)의 중요성을 실감하였기에 국가적으로 공군력 강화에 주안점을 두고 있는 실정이다. 한국 공군도 공군력이 국가방위의 핵심전력이라는 공군의 목표와 버금가는 전략적 접근이 필요하다고 보며 이러한 맥락에서 공군의 F-X사업도 각군간의 사업 분배의 개념이 아닌 국가안보를 위한 강력한 억제력과 미래 불특정한 주변 위협에 대해서도 억제행사를 할 수 있는 능력을 갖출 수 있도록 국가적인 전략으로 추진되어야 한다고 본다. 그래야만 대한민국은 현재 우리 앞에 펼쳐지고 있는 그리고 곧 다가오는 동북아에서 뿐만 아니라 세계 속의 중심세력 국가로 설 수 있을 것이다.