• Journal of Broadcast Engineering
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• v.17 no.1
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• pp.122-128
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• 2012

Because of the system delay caused by the number of feedback retransmission in Distributed Video Coding (DVC) scheme, it is difficult to realize practical DVC in many cases. In this paper low feedback retransmission Distributed Source Coding (DSC) scheme is proposed for practical DVC scheme based on Low-Density Parity-Check (LDPC) codes because DVC system is an specific application of DSC system. This DSC scheme is achieved by using different LDPC codes optimized in each different compression rate and using source revealing scheme. Optimized LDPC codes provide us much better decoding performance which causes the 57% reduced number of iteration. Consequently, the number of feedback retransmission is decreased by 50%.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.309-313
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• 2000

In order to meet the industrial requirement, precision grinding with brush tool has been applied. To analyze the brush tool characteristics, several parameters including numbers of brush string installed in a single holder, depth of cut and brush length have been changed. Several data from various source were acquired using AE, acceleration and tool dynamometer during the process. Consistent results revealing certain trend with respect to each process condition were observed.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.4
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• pp.528-533
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• 2010

This paper describes a calculation method of source level of a ship transient noise, which is one of the important elements for the ship detection. Aim of transient noise measurements is to evaluate of acoustic energy due to singular occurrence, which is therefore defined as non-periodic and short termed events like an attack periscope, a rudder and a torpedo door. In generally, in the case of randomly spaced impulse, the spectrum becomes a broadband random noise with no distinctive pattern. Therefore, frequency analysis is not particularly revealing for type of signal. In the paper, it is performed in time domain to analyze a transient noise. However, a source level of transient noise is required an investigation for multiple frequency band. So, in order to calculate a source level of transient noise, a design of exponential weighting function, convolution, band pass filtering, peak detection, root mean square, and parameter compensation are applied. The effectiveness of this calculation scheme is studied through computer simulations and a sea test. Furthermore, an application of the method is applied in a real case.

• Nuclear Engineering and Technology
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• v.43 no.6
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• pp.583-592
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• 2011

The radiological characteristics for waste classification were assessed for neutron-activated decommissioning wastes from a CANDU reactor. The MCNP/ORIGEN2 code system was used for the source term analysis. The neutron flux and activation cross-section library for each structural component generated by MCNP simulation were used in the radionuclide buildup calculation in ORIGEN2. The specific activities of the relevant radionuclides in the activated metal waste were compared with the specified limits of the specific activities listed in the Korean standard and 10 CFR 61. The time-average full-core model of Wolsong Unit 1 was used as the neutron source for activation of in-core and ex-core structural components. The approximated levels of the neutron flux and cross-section, irradiated fuel composition, and a geometry simplification revealing good reliability in a previous study were used in the source term calculation as well. The results revealed the radioactivity, decay heat, hazard index, mass, and solid volume for the activated decommissioning waste to be $1.04{\times}10^{16}$ Bq, $2.09{\times}10^3$ W, $5.31{\times}10^{14}\;m^3$-water, $4.69{\times}10^5$ kg, and $7.38{\times}10^1\;m^3$, respectively. According to both Korean and US standards, the activated waste of the pressure tubes, calandria tubes, reactivity devices, and reactivity device supporters was greater than Class C, which should be disposed of in a deep geological disposal repository, whereas the side structural components were classified as low- and intermediate-level waste, which can be disposed of in a land disposal repository. Finally, this study confirmed that, regardless of the cooling time of the waste, 15% of the decommissioning waste cannot be disposed of in a land disposal repository. It is expected that the source terms and waste classification evaluated through this study can be widely used to establish a decommissioning/disposal strategy and fuel cycle analysis for CANDU reactors.

• Journal of Software Assessment and Valuation
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• v.17 no.1
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• pp.31-40
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• 2021

Plagiarism refers to the act of using the original data as if it were one's own without revealing the source. The plagiarism of source code causes a variety of problems, including legal disputes. Plagiarism in software projects is usually determined by measuring similarity by comparing every pair of source code within two projects. However, blindly comparing every pair has been a huge computational burden, causing a major factor of not using tools of better accuracy. If we can only compare pairs that are probable to be clones, eliminating pairs that are impossible to be clones, we can concentrate more on improving the accuracy of detection. In this paper, we propose a method of selecting highly probable candidates of clone pairs by pre-classifying suspected source-codes using a machine-learning model called code2vec.

• Archives of design research
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• v.20
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• pp.25-36
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• 1997

Design style is studied to examine the design essence more clearly which is revealed as a formative substance. First of all, every effort can be made to understand the peculiar characteristic of design style by considering the linguistic source and meaning of design style. On the basis of this, picturesque style, mechanical style and expressive style are searched to establish the types of design style, inspect the every style's characteristic and focus on revealing the relations between the creation of design value and the style. Finally, changing factors of design style is researched to suggest the effect and direction of design development.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.45.1-45.1
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• 2017

A Korean VLBI Network Key Science Program, the Interferometric Monitoring of Gamma-ray Bright AGNs (iMOGABA) program continues to aim at revealing the origins of the gamma-ray flares that are often detected in active galactic nuclei (AGNs). Here in this presentation, we would like to present what we have learned about the Gamma-ray bright AGNs based on the recent results of the Korean VLBI Network Key Science Program: the iMGOABA. The results will include a) the source properties of the whole samples obtained from a single-epoch observation, and b) some of scientific highlights for the iMOGAGBA on specific sources. From those highlighted works, we find that the Gamma-ray bright AGNs become fainter at higher frequencies, yielding optically thin spectra at mm wavelengths. Based on the studies on specific sources, taking into account the synchrotron self-absorption model of the relativistic jet, we estimated the magnetic field strength in the mas emission region during the observing period.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.11
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• pp.1056-1060
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• 2005

We investigated the fabrication and characteristics of the nitride-based spin-polarized LEDs with room-temperature ferromagnetic (Ga,Mn)N layer as a spin injection source. The (Ga,Mn)N thin films having room-temperature ferromagnetic ordering were found to exhibit the negative MR and anomalous Hall resistance up to room temperature, revealing the existence of spin-polarized electrons in (Ga,Mn)N films at room temperature. The electrical characteristics in the spin LEDs did not degraded in spite of the insertion of the (Ga,Mn)N layer into the LED structure. In EL spectra of the spin LEDs, it is confirmed that the devices produce intense EL emission at 7 K as well as room temperature. These results are expected to open up new opportunities to realize room-temperature operating semiconductor spintronic devices.

• International Journal of Contents
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• v.15 no.2
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• pp.13-19
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• 2019

This research demonstrates a clear visual outline of character influence-relations in creating Jungian character archetypes in films using R computational technology. It contributes to the integration of Jungian analytical psychology into film studies by revealing character network relations in film. This paper handles character archetypes and their influence on developing other character archetypes in films in regards to network analysis drawn from Lynn Schmidt's analysis of 45 master characters in films. Additionally, this paper conducts a character network analysis visualization experiment using R open-source software to create an easily reproducible tutorial for scholars in humanities. This research is a pioneering work that could trigger the academic communities in humanities to actively adopt data science in their research and education.

• Communications for Statistical Applications and Methods
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• v.31 no.1
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• pp.55-64
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• 2024

In this study, we consider the sample size determination problem for clustered count data with many zeros. In general, zero-inflated Poisson and binomial models are commonly used for zero-inflated data; however, in real data the assumptions that should be satisfied when using each model might be violated. We calculate the required sample size based on a discrete Weibull regression model that can handle both underdispersed and overdispersed data types. We use the Monte Carlo simulation to compute the required sample size. With our proposed method, a unified model with a low failure risk can be used to cope with the dispersed data type and handle data with many zeros, which appear in groups or clusters sharing a common variation source. A simulation study shows that our proposed method provides accurate results, revealing that the sample size is affected by the distribution skewness, covariance structure of covariates, and amount of zeros. We apply our method to the pancreas disorder length of the stay data collected from Western Australia.