• Journal of Information Processing Systems
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• 제14권1호
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• pp.56-78
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• 2018

Security issue in mobile ad hoc network (MANET) is a promising research. In 2011, we had accomplished a survey of black hole attacks in MANETs. However network technology is changing with each passing day, a vast number of novel schemes and papers have been proposed and published in recent years. In this paper, we survey the literature on malicious attacks in MANETs published during past 5 years, especially the black hole attack. Black hole attacks are classified into non-cooperative and collaborative black hole attacks. Except black hole attacks, other attacks in MANET are also studied, e.g., wormhole and flooding attacks. In addition, we conceive the open issues and future trends of black hole detection and prevention in MANETs based on the survey results of this paper. We summarize these detection schemes with three systematic comparison tables of non-cooperative black hole, collaborative black hole and other attacks, respectively, for a comprehensive survey of attacks in MANETs.

• 영미문화
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• 제14권1호
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• pp.1-26
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• 2014

Multicultural theories fully fledged around the 1980s and the early 1990s. Emerging in the 1960s thanks to the Civil Rights movement, multiculturalism has become the grand American national narratives, whose tenets recognize and respect people with diverse racial and cultural backgrounds. This period, however, witnessed the eruption of violent and destructive rebellions or uprisings involving racial minorities. Racial conflicts and tensions exploded at the moment when multiculturalism was widely practiced in areas including education and public policy revealing that complicated problems are embedded in the urban ghettos. American popular culture, specifically addresses antagonisms among different races or ethnicities in Bed-Stuy in New York. Although the film is mainly concerned with the collision among races, it lets ambivalent and cacophonous values and ideologies be present in the black community. On the other hand, Ice Cube's "Black Korea" empowers the black community when it deals with the turbulent relationship between black residents and Korean American merchants. Simultaneously, it denigrates Korean Americans as gasta raps often target the institution like government or police. In short, while attempts to search the ideas of coexistence and juxtaposition through polyphonic features embodied in the film "Black Korea" seems to depend on the dualistic system when it deals with the black-Korean conflicts and as a result it just reveals the chasm between two communities.

• 대한수학회논문집
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• 제24권4호
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• pp.617-628
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• 2009

We present an efficient and accurate finite-difference method for computing Black-Scholes partial differential equations with multiunderlying assets. We directly solve Black-Scholes equations without transformations of variables. We provide computational results showing the performance of the method for two underlying asset option pricing problems.

• 천문학논총
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• 제16권1호
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• pp.1-5
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• 2001

In this review article we introduce the 'H-R diagram' of black holes. Some fundamental concepts of black hole thermodynamics and electrodynamics are also summarized in detail.

• 대한기계학회논문집B
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• 제38권1호
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• pp.17-24
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• 2014

본 연구에서는 교외지역 대기 에어로졸의 특성을 파악하기 위하여 지구온난화와 밀접한 관련이 있다고 알려진 블랙카본 농도를 측정하였고, 그 결과들을 기상 요소들과 비교하였다. 필터 기반 측정 장치인 MAAP (Multi Angle Absorption Photometer)를 이용하여 측정된 블랙카본 농도와 황사농도, 습도, 온도 및 풍속을 비교하였다. 블랙카본 농도는 4~5월에 높으며 6~9월에 낮은 경향을 보였다. 블랙카본 농도는 PM10(직경 $10{\mu}m$ 이하 입자상 물질) 농도 및 습도와는 비례관계를 보였으며 온도 및 풍속과는 반비례 관계를 보였다. 또한 디젤엔진에서 발생한 블랙카본의 직경 및 광흡수 계수 및 수농도를 측정하여 흡수 단면적을 도출 하였고 이를 통하여 교외 지역 블랙카본의 수준을 평가 할 수 있는 방법을 소개하였다.

• 한국축산식품학회지
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• 제37권4호
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• pp.552-560
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• 2017

This study aimed to evaluate the quality characteristics of Tteokgalbi with 1% (w/w) black rice bran only (T1), or with black rice bran and one of the following four types of organic acid: ascorbic acid (T2), citric acid (T3), tartaric acid (T4), or maleic acid (T5) as a substitute for caramel colorant. Tteokgalbi with only black rice bran showed the highest (p<0.05) values of moisture content and water holding capacity (WHC), while there were no significant differences in protein content, fat content, ash content, and thiobarbituric acid reactive substance (TBARS) values in treatments and controls (p>0.05). All the treated samples with any one of the four organic acids showed lower pH than controls (p<0.05). The lightness and redness of Tteokgalbi treated with any one of the four organic acids and black rice bran were higher than those of T1. The volatile basic nitrogen (VBN) values of T4 and T5 were higher than those of the other treatments (p<0.05). With regards to sensory characteristics, T1 and T2 showed overall acceptability similar to that of the controls (p>0.05). The results reported in this study show that Tteokgalbi with black rice bran and any one of the four organic acids listed above not only improved quality characteristics in cooking loss, WHC, lipid oxidation but also could successfully replace the synthetic caramel colorant. Overall, the most satisfactory results were obtained by adding black rice bran and ascorbic acid.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2003년도 추계종합학술대회 논문집
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• pp.352-366
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• 2003

Exploiting a multiply warped products manifold scheme, we study the interior solutions of the (2.1) Banados-Teitelboim-Zanelli black holes and the exterior solutions of the (2+1) do Sitter black holes.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2002년도 하계학술발표대회 논문집 제21권 1호
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• pp.377-380
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• 2002

Acoustic Characteristics of Nitrile Butadiene Rubber with Carbon Black ContentAcoustic and mechanical properties of Nitrile Butadiene Rubbers (NBR) with the variation of the carbon black content were investigated. NBR where the acrylonitrile content is $33\%$ based on the mole percent has been prepared with fixed sulfur content for vulcanization. Acoustic measurement of the prepared rubbers were peformed in the frequency region of $300\;\~\;1000\;kHz$. Their mechanical properties such as density, hardness were also measured. Increase of the carbon black content in the rubber resulted in enhancement of the mechanical property and linear increase of the sound speed as function of the carbon black content. Interestingly, attenuation of the sound speed was only affected by the existence of the carbon black and not by the amount of carbon black in the experiment range of this article. In this study, it was found that the amount of carbon black content in the NBR was correlated with the acoustic properties and can be estimated nondestructively by the measurement of the specific acoustic property.

• 한국재료학회지
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• 제18권12호
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• pp.683-688
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• 2008

For development of a human body model for electric shock, electroconductive paints with carbon black as a filler material were developed. The characteristics of the volume resistivities of thin films fabricated using the electroconductive paints were investigated as a function of the particle sizes and content of carbon black. With a carbon black particle size over $80\;{\mu}m$, agglomeration of carbon black powders was observed. The volume resistivity of the particles increased as the porosity increased and as the amount of carbon black decreased due to the agglomeration of carbon black powders. With a particle size of $4\;{\mu}m$ and $20\;{\mu}m$, agglomeration of carbon black powders was not observed and their porosities were measured as 0.86% and 1.12% with volume resistivities of $20\;{\Omega}{\cdot}cm$ and $80\;{\Omega}{\cdot}cm$ respectively. A carbon black particle size of less than $20\;{\mu}m$ is considered to be suitable as a type of electric-shock electroconductive paint for a human body model.

• 한국인공지능학회지
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• 제11권3호
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• pp.17-22
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• 2023

In this paper, we propose a black ice detection system using Convolutional Neural Networks (CNNs). Black ice poses a serious threat to road safety, particularly during winter conditions. To overcome this problem, we introduce a CNN-based architecture for real-time black ice detection with an encoder-decoder network, specifically designed for real-time black ice detection using thermal images. To train the network, we establish a specialized experimental platform to capture thermal images of various black ice formations on diverse road surfaces, including cement and asphalt. This enables us to curate a comprehensive dataset of thermal road black ice images for a training and evaluation purpose. Additionally, in order to enhance the accuracy of black ice detection, we propose a multi-scale dilation convolution feature fusion (MsDC-FF) technique. This proposed technique dynamically adjusts the dilation ratios based on the input image's resolution, improving the network's ability to capture fine-grained details. Experimental results demonstrate the superior performance of our proposed network model compared to conventional image segmentation models. Our model achieved an mIoU of 95.93%, while LinkNet achieved an mIoU of 95.39%. Therefore, it is concluded that the proposed model in this paper could offer a promising solution for real-time black ice detection, thereby enhancing road safety during winter conditions.