• Nuclear Engineering and Technology
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• 제9권3호
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• pp.125-137
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• 1977

천연 산화 우라늄 핵연료와 중수 감속재를 사용하는 월성 1호기에 관한 온도 계수를 조사하였다. 핵연료, 감속재 및 냉각재 온도변화에 따른 중성자의 유효 증배 인자의 변화를 계산하였다. 계산된 결과를 LATREP 전자계산 code에 의한 온도 계수 값들과 비교하였다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권1호
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• pp.101-109
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• 2017

This paper presents a high-throughput low-complexity 512-point eight-parallel mixed-radix multipath delay feedback (MDF) fast Fourier transform (FFT) processor architecture for orthogonal frequency division multiplexing (OFDM) applications. To decrease the number of twiddle factor (TF) multiplications, a mixed-radix $2^4/2^3$ FFT algorithm is adopted. Moreover, a dual-path shared canonical signed digit (CSD) complex constant multiplier using a multi-layer scheme is proposed for reducing the hardware complexity of the TF multiplication. The proposed FFT processor is implemented using TSMC 90-nm CMOS technology. The synthesis results demonstrate that the proposed FFT processor can lead to a 16% reduction in hardware complexity and higher throughput compared to conventional architectures.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 II
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• pp.1213-1216
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• 2003

This paper proposes an 3D graphics rendering processor for portable device. One the most important factor is chip size for portable device, but the conventional 3D graphics rendering processor is not a suitable because the processor needs a lot of multiplication and division units. So the proposed architecture substitutes single precision floating point by 32 bit fixed point, and uses recursive units for the same operation such as color values(z, r, g, b, a) and texture values (s, t, u, v). In this approach, we reduce numbers of multiplications and divisions by 66.1% and 75% respectively at the sacrifice of performance degradation by 2.12%.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권12호
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• pp.6260-6276
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• 2019

With the rapid development of cloud computing, it raises real questions on privacy protection, which greatly limits the use of cloud computing. However, fully homomorphic encryption (FHE) can make cloud computing consistent with privacy. In this paper, we propose a simpler FHE scheme based on ring LWE problem, with a smaller size of ciphertext and a lower noise-expansion factor for homomorphic multiplication. Then based on our optimized RLWE-based FHE scheme, we propose a fast single-database private information retrieval protocol, combining with batching and number theoretic transform technology.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(2)
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• pp.937-942
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• 1995

Great interest has prompted Boron Neutron Capture Therapy (BNCT) as a new treatment for brain tumors. The use of $^{252}$Cf as a neutron source for BNn makes the in-hospital treatments of tumors to be possible. Newly proposed subcritical multiplying assemblies (SMA) are explored to improve relatively tow neutron fluxes of the source and construct the feasibilities of $^{252}$Cf as a neutron source. The MCNP code has been used to evaluate the effective multiplication factor of the entire system and the intensities and percentages of epithermal neutron flux at the patient-end surface of the system. The neutron beam using SMA shows the epithermal neutron flux enhancement of about 13 times as large as the beam without using SMA. It is expected that the neutron beam proposed in this research will be more effective for treatment of tumors due to the increased therapeutic neutron fluxes.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 추계학술발표회논문집(1)
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• pp.19-24
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• 1997

In this study, we extend the application of the interface-matrix(IM) method for reflector modeling to Analytic Flux Expansion Nodal (AFEN) method. This include the modifications of the surface-averaged net current continuity and the net leakage balance conditions for IM method in accordance with AFEN fomular. AFEN-interface matrix (AFEN-IM) method has been tested against ZION-1 benchmark problem. The numerical result AFEN-IM method shows 1.24% of maximum error and 0.42% of root-mean square error in assembly power distribution, and 0.006%Δk of neutron multiplication factor. This result proves that the interface-matrix method for reflector modeling can be useful in AFEN method.

• Nuclear Engineering and Technology
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• 제14권4호
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• pp.163-171
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• 1982

평가핵자료파일 ENDF/B-IV 및 ENDL-78과 군정수 계산용 전산코드 ETOX-K4를 이용하여 고속로 핵계산을 위한 ABBN형 26군 군정수쎄트 KAERI-26G를 생산하였다. 이 쎄트를 이용하여 여러형태의 고속임계로심들에 대한 유효증배계수, 반응율비, 반응-도계수등의 적분실험치를 해석하고 기 연구발표된 같은 형의 군정수쎄트에 대한 연구결과와도 비교하여 생산된 군정수쎄트의 신뢰도를 평가하였다.

• 한국연소학회지
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• 제1권2호
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• pp.51-58
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• 1996

The coherent flamelet model(CFM) is applied to symmetric counterflow turbulent premixed flames. The flame source term is set proportional to the turbulence intensity to reproduce the experimental correlation of Abdel-Gayed et al. for the turbulent burning velocity. Flame quenching by the turbulent rate of strain is modeled by an additional multiplication factor to the flame source term. A modified form of CFM is employed to consider coexistence of burned and unburned premixture with ambient air. The predicted flame position and turbulent flow field coincide well with the experimental data of Kostiuk et al., although there is some discrepancy in the radial rms velocity component and integral length scale near the symmetric plane.

• 한국정보전자통신기술학회논문지
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• 제11권5호
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• pp.475-480
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• 2018

In OFDM-based systems, FFT is a critical component since it occupies large area and consumes more power. In this paper, we present a low hardware-cost and low power 512-point pipelined FFT design method for OFDM applications. To reduce the number of twiddle factors and to choose simple design architecture, the radix-$2^4-2^3$ algorithm are exploited. For twiddle factor multiplication, we propose a new canonical signed digit (CSD) complex multiplier design method to minimize the hardware-cost. In hardware implementation with Intel FPGA, the proposed FFT design achieves more than about 28% reduction in gate count and 18% reduction in power consumption compared to the previous approaches.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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• pp.148-153
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• 1996

In this paper, an effective method for resolving difficulty resulting from the heterogeneity of the PWR baffle/reflector region is developed on the basis of the AFEN method. The essential difference of the new method from the conventional approach based on the equivalence theory is that the heterogeneous baffle/reflector is directly, without homogenization, considered as a node in nodal calculation Numerical results show that AFEN method with the new method can accurately predict both the multiplication factor and the power distribution of thermal reactors with baffle explicitly modeled.