• 방송공학회논문지
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• 제17권1호
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• pp.122-128
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• 2012

본 논문에서는 실제적으로 사용 가능한 분산 비디오 부호화 (Distributed Vedio Coding, DVC) 시스템을 구현하기 위하여 기존의 문제였던 높은 피드백 재전송 횟수에 의한 복원 지연문제를 개선하는 방법을 제안한다. 이는 각 압축률 영역에 맞추어 설계된 저밀도 패리티 검사 (Low-Density Parity-Check, LDPC) 부호를 사용함으로써 복원 성능을 높이고 각 부호가 복호에 실패할 경우 다른 부호율의 LDPC 부호를 구성하기 위한 소스 공개 (Source Revealing) 기법을 사용하여 피드백 전송 수를 줄임으로써 문제를 해결한다. 모의 실험 결과, 제안된 방법에 따른 DVC 방법은 기존 방법에 비해 57%의 복호 성능 개선 효과를 얻어 피드백 재전송 횟수를 50% 이상 감소시켰다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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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.

• 한국군사과학기술학회지
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• 제13권4호
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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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• 제43권6호
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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.

• 한국소프트웨어감정평가학회 논문지
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• 제17권1호
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• pp.31-40
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• 2021

소스코드 표절은 원본 자료의 출처를 분명히 밝히지 않고 자신의 것처럼 사용하는 행위를 말한다. 소스코드 표절로 인한 문제는 법적인 분쟁을 다투는 경우까지 다양한 문제를 일으킨다. 소스코드의 표절 여부는 일반적으로 비교 대상 소프트웨어 프로젝트 내의 각 소스코드를 전수 비교하여 유사도를 측정하여 결정한다. 전수 비교는 표절 가능성이 전혀 없는 코드도 비교 대상에 포함하기 때문에 그만큼의 시간을 헛되이 소모한다. 소스코드 표절로 의심되는 비교 쌍만 선별하여 비교할 수 있으면 그만큼 비교 횟수는 줄어들게 되어 탐지 도구의 실행 속도를 향상시킬 수 있을 뿐만 아니라, 표절 가능성이 높은 부분만을 대상으로 탐지의 정확도를 높이는데 집중할 수도 있다. 본 논문에서는 code2vec 이라는 기계학습 모델을 활용하여 코드 클론으로 의심되는 소스코드들을 미리 분류하여 비교 횟수를 줄임으로써 소스코드 표절 탐지의 성능을 개선할 수 있음을 보인다.

• 디자인학연구
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• 제20권
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• pp.25-36
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• 1997

조형적 실체로 구체화되는 디자인의 본질을 좀 더 정확히 파악하기 위하여 디자인 양식에 대해 고찰하였다. 우선 디자인 양식에 대한 어원적 유래와 의미에 대하여 탐구함으로써 디자인 양식의 독특한 성격을 이해하는데 주력했다. 이를 토대로 하여 우미 양식, 기계양식, 표현양식을 집중적으로 고찰하여 디자인 양식의 유형을 정립하고, 각 양식이 지니고 있는 특수성을 파악하여, 그것이 디자인의 가치 창출과 어떤 상관관계를 이루고 있는가를 밝히려는데 초점을 맞추었다. 끝으로 디자인 양식의 변화요인에 대해 알아보고, 양식의 변화가 디자인 발전에 미치는 영향과 방향을 제시하였다.

• 천문학회보
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• 제42권2호
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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.

• 한국전기전자재료학회논문지
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• 제18권11호
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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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• 제15권2호
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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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• 제31권1호
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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.