• Journal of Astronomy and Space Sciences
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• v.14 no.1
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• pp.33-43
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• 1997

New BVR CCD photometric observations of EB type close binary V388 Cyg were obtained at the Sobaeksan Astronomy Observatory during 10 nights from October to December 1995. We analyse new 3 color (B, V & R) light curves simultaneously using the Wilson-Devinney code. Now, it is not yet clear whether V388 Cyg is contact or semidetached system. Published epochs of times of minima to data were used to study the changes in period of the system, and calculated a new light elements with the secular terms, $-4.83{\times}10^{-10}$, which indicated the continuous decrease of the period.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.5
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• pp.631-640
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• 2013

This paper provides a comparison of the J-integral estimation method under combined primary and secondary stress in the R6, RCC-MR A16 code. The comparisons of each code are based on finite element analysis using ABAQUS with regard to the crack shape, crack depth, and magnitude of secondary load. The estimate of the R6 code is conservative near $L_r=1$, and that of the RCC-MR A16 code is conservative near $L_r=0$. As a result, this paper proposes a modified method of J-integral estimation in the R6, RCC_MR A16 code. The J-integral using the modified method corresponds to the finite element analysis result.

• Journal of Radiation Protection and Research
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• v.34 no.2
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• pp.69-75
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• 2009

To obtain precise information about characteristics of gamma ray detector system responses, we developed new GUI computer program to analize full-energy absorption peak using our developed Delphi computer code for educational purpose. By use of the well known 4 nonlinear peak shaping functions, peaks were fitted with least square fit method in this code. In this paper, we described the methods to search for 12 coefficients in above 4 nonlinear peak shaping functions by use of our developed code in details. The computer code was tested for 1 $\mu$Ci $^{137)Cs$ 661 keV gamma ray peak spectrum detected by 25 % relative efficiency HPGe detector with 5.35 cm (D) $\times$ 5.5 cm (L) size.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.5
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• pp.1019-1026
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• 2019

Due to limitations of existing methods for detecting newly introduced malware, the importance of the development of artificial intelligence vaccines arises. Existing artificial intelligence vaccines have a disadvantage that the accuracy of the detection rate is low because those vaccines do not scan all parts of the file. In this paper, we suggest an enhanced method for detecting malware which is composed of unique OP Code features in the malware files. Specifically, we tested the method with text datasets trained on Random Forest algorithm and with image datasets trained on the Inception V3 model. As a result, the highest accuracy of the detection rate was about 80%.

• 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 Radiation Protection and Research
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• v.11 no.1
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• pp.29-36
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• 1986

GESS-a computer code for simulation of energy spectra for gamma-ray in NaI(T1) scintillator has been developed. The Monte Carlo method was employed to simulate physical behaviours of particle transport in a medium. In the processes of simulation, all the interaction processes such as Rayleigh and Compton scattering, photoelectric effect and pair production were considered. The resulting electron slowing down spectrum was also considered with the CSDA model. For the purpose of verification of the code, a measurement gamma spectrum for incident gamma energy of 1.33 MeV was performed. The measured values appeared to be slightly higher than the theoretically calculated values.

• Advances in aircraft and spacecraft science
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• v.8 no.1
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• pp.1-15
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• 2021

Mars exploration demands aerodynamic computations for a proper design of missions of spacecraft carrying instruments and astronauts to Mars. Both Computational Fluid Dynamics (CFD) and Direct Simulation Monte Carlo (DSMC) method play a key role for this purpose. To the author's knowledge, the altitude separating the fields of applicability of CFD and DSMC in Mars atmosphere entry is not yet clearly defined. The limitations in using DSMC at low altitudes are due to technical limitations of the computer. The limitations in using CFD at high altitudes are due to thermodynamic non-equilibrium. Here, this problem is studied in Mars atmosphere entry, considering the Mars Pathfinder capsule in the altitude interval 40-80 km, by means of a DSMC code. Non-equilibrium is quantified by the relative differences between translational temperature and: rotational (θt-r), vibrational (θt-v), overall (θt-ov) temperatures, anisotropy is quantified by the relative difference between the translational temperature component along x and those along y (θx-y) and along z (θx-z). The results showed that θt-r, θt-v, θx-y, θx-z are almost equivalent. The altitude of 45 km should be the limit altitude for a proper use of a CFD code and the altitude of 40 km should be the limit altitude for a reasonable use of a DSMC code.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.525-540
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• 2023

Because of a new seismic design code has been enacted in 2023, there is a need to evaluate whether the road tunnels in operation satisfies the requirements of the new code. Four tunnels that are considered to be most susceptible to damage. Time history analyses are performed to quantify their seismic performances. The input ground motions generated to fit both 2007 and 2023 codes are used to evaluate the effect of the motions on the calculated responses. The analyses show that all tunnels perform favorably and satisfies the requirements successfully. Therefore, retrofit or reinforcement are deemed as unnecessary.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.3 no.2
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• pp.22-29
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• 1992

In recent years there has been increased interest in a class of multiple-access techniques known as code division multiple-access(CDMA). As the trend for ever increasing data transmission rate and high error performance continues while conserving bandwidth, the needs arise for good highrate R=b/v convolu- tional codes such as punctured codes. In this paper, the packet error propability has been analyzed in code division multiple-access packet radio system which utilize punctured convolutional code and hard-decision Viterbi decoding.

• 한국전산유체공학회:학술대회논문집
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• 2007.10a
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• pp.194-199
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• 2007

IB (immersed boundary) method is one of the prominent tool in computational fluid dynamics for the analysis of flows over complex geometries. The IB technique simplyfies the solution procedure by eliminating the requirement of complex body fitted grids and it is also superior in terms of memory requirement. In this study we have developed numerical code (FOTRAN) for the analysis of 2D flow over a cylinder using IB technique. The code is validated by comparing the wake lengths and separation angles given by Guo et. al. We employed fractional-step procedure for solving the Navier-Stokes equations governing the flow and discrete forcing IB technique for imposing boundary conditions. Also we have developed a 3D code for the backward-facing-step flow and flow over a sphere. The reattachment length in backward-facing-step flow was compared with the one given by Nie and Armaly, which has proven the validity of our code.