• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권3호
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• pp.894-907
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• 2022

The features extracted by convolutional neural networks are more descriptive of images than traditional features, and their convolutional layers are more suitable for retrieving images than are fully connected layers. The convolutional layer features will consume considerable time and memory if used directly to match an image. Therefore, this paper proposes a feature weighting and region integration method for convolutional layer features to form global feature vectors and subsequently use them for image matching. First, the 3D feature of the last convolutional layer is extracted, and the convolutional feature is subsequently weighted again to highlight the edge information and position information of the image. Next, we integrate several regional eigenvectors that are processed by sliding windows into a global eigenvector. Finally, the initial ranking of the retrieval is obtained by measuring the similarity of the query image and the test image using the cosine distance, and the final mean Average Precision (mAP) is obtained by using the extended query method for rearrangement. We conduct experiments using the Oxford5k and Paris6k datasets and their extended datasets, Paris106k and Oxford105k. These experimental results indicate that the global feature extracted by the new method can better describe an image.

• 천문학회보
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• 제43권1호
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• pp.57.1-57.1
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• 2018

Reionisation in the early Universe is likely driven by dwarf galaxies. Using cosmological RHD simulations, we study star formation and the escape of Lyman continuum (LyC) photons from mini-haloes with Mhalo<108Msun. We find that feedback reduces star formation very efficiently in mini-haloes, resulting in the stellar mass consistent with the empirical stellar mass-to-halo mass relation derived in the local Universe. Because star formation is stochastic and dominated by a few gas clumps, the escape fraction in mini-haloes is generally determined by photo-ionization, rather than supernova explosions. We find that the photon number-weighted mean escape fraction in mini-haloes is higher (20-40%) than that in atomic-cooling haloes. Despite their high escape fractions, LyC photons from mini-haloes are of minor importance for reionization due to inefficient star formation. We confirm previous claims that stars in atomic-cooling haloes with masses $10^8M_{sun}$$10^{11}M_{sun}$ are likely to be the most important source of reionization.

• 천문학회보
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• 제45권1호
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• pp.39.1-39.1
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• 2020

We examine how the mass assembly of central galaxies depends on their location in the cosmic web. The HORIZON-AGN simulation is analysed at z~2 using the DISPERSE code to extract multi-scale cosmic filaments. We find that the dependency of galaxy properties on large-scale environment is mostly inherited from the (large-scale) environmental dependency of their host halo mass. When adopting a residual analysis that removes the host halo mass effect, we detect a direct and non-negligible influence of cosmic filaments. Proximity to filaments enhances the build-up of stellar mass, a result in agreement with previous studies. However, our multi-scale analysis also reveals that, at the edge of filaments, star formation is suppressed. In addition, we find clues for compaction of the stellar distribution at close proximity to filaments. We suggest that gas transfer from the outside to the inside of the haloes (where galaxies reside) becomes less efficient closer to filaments, due to high angular momentum supply at the vorticity-rich edge of filaments. This quenching mechanism may partly explain the larger fraction of passive galaxies in filaments, as inferred from observations at lower redshifts.

• 천문학회보
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• 제43권2호
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• pp.32.3-32.3
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• 2018

We use the synthetic light-cone from the cosmological hydrodynamical simulation Horizon-AGN to produce a mock photometric galaxy catalogue on the redshift range 0

• 충청수학회지
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• 제9권1호
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• pp.27-60
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• 1996

We compute low order terms of automorphisms of a quadric CR manifold defined by $v^a$ =< $A^az$, z > where there is a real vector ${\kappa}{\in}R^m$ such that $det({\kappa}{\cdot}A){\neq}0$.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 추계학술대회
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• pp.201-202
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• 2018

본 논문에서는 기존 ImageNet과 Oxford-IIIT Pet Image의 Dataset에서 제공하는 개 품종 이미지와 인터넷 상에서 개 품종 이미지를 데이터 마이닝을 통해 획득된 개 품종 이미지를 결합하고 Random-Label을 추가 하여 개 품종 122개의 클래스와 개 품종이 아닌 1개의 클래스를 인식하는 방법에 대해 소개 한다. 기존 DB만을 사용하였을 때 개 품종 인식률 대비 기존 DB와 수집 DB를 모두 사용한 개 품종 인식률이 Top-1에 대해서 1.5% 개선되었다. 개가 아닌 이미지 인식은 랜덤 DB를 10000장의 경우 93% 인식률을 확인했다.

• 대한의생명과학회지
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• 제28권2호
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• pp.67-82
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• 2022

The prevalence of SARS-CoV-2 led to inconsistent public health policies that resulted in COVID-19 containment failure. These factors resulted in increased hospitalization and death. To prevent viral spread and achieve herd immunity, the only safe and effective measure is to provide to vaccinates. Ever since the release of the SARS-CoV-2 nucleotide sequence in January of 2020, research centers and pharmaceutical companies from many countries have developed different types of vaccines including mRNA, recombinant protein, and viral vector vaccines. Prior to initiating vaccinations, phase 3 clinical trials are necessary. However, no vaccine has yet to complete a phase 3 clinical trial. Many products obtained "emergency use authorization" from governmental agencies such as WHO, FDA etc. The Korean government authorized the use of five different vaccines. The viral vector vaccine of Oxford/AstraZeneca and the Janssen showed effectiveness of 76% and 66.9%, respectively. The mRNA vaccine of Pfizer-BioNTech and Moderna showed effectiveness of 95% and 94.1%, respectively. The protein recombinant vaccine of Novavax showed an effectiveness of 90.4%. In this review, we compared the characteristics, production platform, synthesis principles, authorization, protective effects, immune responses, clinical trials and adverse effects of five different vaccines currently used in Korea. Through this review, we conceptualize the importance of selecting the optimal vaccine to prevent the COVID-19 pandemic.

• 영어영문학
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• 제60권2호
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• pp.211-232
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• 2014

In late Victorian England, a "pervert" meant two things. One meaning designated a person who "turned" or converted from one sect of Christianity to another. In Wilde's time this referred specifically to converts from the established state Church of England to the transnational Roman Catholic Church. The other, newer meaning designated someone who turned from conventional heterosexual relations to a (as yet unnamed) homosexual orientation. In the context of the late Victorian empire, both were considered dangerous. The rising social and political influence of Roman Catholicism appeared threatening as a transnational Church invading a national one. For the Anglican Church of England, this crisis was played out what came to be known as the Oxford Movement, still influential during Wilde's time as a student there from 1874 to 1878. What is interesting in Wilde's life, as in his work, is the way he himself played with the dangerous transgressions inherent in being a "pervert." Sexually, he was converted to same-sex love while still a married man. In terms of religion, he remained fascinated with Catholicism, allegedly converting on his death-bed. But what is provocative is way that Wilde used one "perversion" to play into another: so that in such works as The Picture of Dorian Gray and Salome, his version of a kind of anti-Catholic Catholicism becomes a site of sexual desire, and sexual desire expression for that kind of spirituality, which, as unrequited longing, can ultimately n find no object adequate to its imagination.

• 천문학회보
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• 제34권1호
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• pp.75.1-75.1
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• 2009

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2009년도 한국우주과학회보 제18권1호
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• pp.39.3-39.3
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• 2009