• ETRI Journal
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• 제42권3호
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• pp.446-458
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• 2020

In this study, an efficient scheme for hiding data directly in partially encrypted versions of high efficiency video coding (HEVC) videos is proposed. The content owner uses stream cipher to selectively encrypt some HEVC-CABAC bin strings in a format-compliant manner. Then, the data hider embeds the secret message into the encrypted HEVC videos using the specific coefficient modification technique. Consequently, it can be used in third-party computing environments (more generally, cloud computing). For security and privacy purposes, service providers cannot access the visual content of the host video. As the coefficient is only slightly modified, the quality of the decrypted video is satisfactory. The encrypted and marked bitstreams meet the requirements of format compatibility, and have the same bit rate. At the receiving end, data extraction can be performed in the encrypted domain or decrypted domain that can be adapted to different application scenarios. Several standard video sequences with different resolutions and contents have been used for experimental evaluation.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.529-532
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• 2007

In order to characterize the thermal conductivity and viscosity of grout materials used for backfilling ground heat exchangers, nine bentonite grouts and cement grouts being adapted in the United State have been considered in this study. The bentonite grouts indicate that the thermal conductivity and viscosity increase with the content of bentonite or filler (silica sand). In addition, material segregation can be observed when the viscosity of grout is relatively low. The saturated cement grouts appear to possess much higher thermal conductivity than the saturated bentonite grouts, and the reduction of thermal conductivity in the cement grouts after drying specimens is less than in case of the bentonite grouts. Maintaining the moisture content of grouts is a crucial factor in enhancing the efficiency of ground heat exchangers.

• East Asian mathematical journal
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• 제38권4호
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• pp.517-532
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• 2022

This study looked at how content reviews with mathematical games in class would influence the mathematical disposition of middle school students. In doing so, three games adapted from prior research were used as a supplementary instruction after school hours over three months. The mathematical topics of the games involved concepts of probability and trigonometry at the middle school level. The results of the pre- and post-survey on mathematical disposition indicate that incorporating mathematical games appeared to have some positive impacts on whether students might be more eager to learn mathematics and actually put more effort in learning materials.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제13권6호
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• pp.343-357
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• 2007

본 논문에서는 사용자에게 적응화된 콘텐츠를 서비스를 제공하기 위해 필요한 프로파일들을 효율적으로 관리하기 위한 기법들을 제안한다. 프로파일들은 사용자에게 적응화된 서비스를 제공하기 위해 사용자 관련 정보들로 구성되며 사용자 디바이스, 프로파일 저장소, 콘텐츠 적응화 서버, 콘텐츠 저장 서버간에 주기적 비주기적 또는 이벤트에 따라 교환이 가능해야 한다. 또한 프로파일들은 적응화된 콘텐츠 서비스를 위해 프로파일을 필요로 하는 콘텐츠 제공 업체들에게 제공되어야 한다. 이와 같은 기능들을 효율적으로 지원하기 위해 필요한 프로파일 관리 기술을 제안하고, 이를 지원하는 프로파일 관리 프레임워크를 설계한다. 제안된 프로파일 관리 프레임워크에서는 사용자의 다양한 정보를 이용하여 프로파일을 구성하였으며 다양한 디바이스와 플랫폼에 관계없이 프로파일 교환 및 제공을 위해 웹 서비스를 사용하였다. 또한 프로파일의 효율적인 운영을 위해 메타데이타 구성 방법, 동적 구성 방법, 가중치를 이용한 제공 방법 등을 프레임워크에 적용하였다. 성능평가 결과 프로파일 관리 기술에 제안된 기법들이 프로파일 처리에 효율적임을 나타내었다.

• 한국작물학회지
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• 제43권1호
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• pp.54-58
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• 1998

Four introduced forage rape cultivars 'Akela', 'Ramon', 'Sparta', and 'Velox' and a leading rapeseed cultivar Hall-ayuchae were seeded on 1 October 1994 on 20-cm rows at seeding rates of 3, 5, 7, 10, 13, and IS kg/ha to select the best adapted forage rape cultivars and to determine the optimum seeding rate in the Cheju area. Days to flowering of each cultivar was not significantly affected by seeding rate. Average plant height increased from 151 to 164 cm as seeding rate increased from 3 to 10 kg/ha and then decreased to 156 cm at 15 kg/ha. Stem diameter linearly decreased with increasing seeding rate. The optimum seeding rate for the greatest dry matter and protein yields of five cultivars ranged from 10.7 to 11.8 and 10.8 to 14.4 kg/ha, respectively. Dry matter yields of five cultivars ranged from 7.72 and 22.01 Mg/ha. Sparta produced the greatest dry matter yield, followed by Akela, Ramon, Hallayuchae, and Velox. Crude protein yields of five cultivars ranged from 0.29 to 1.08 Mg/ha. Sparta produced the greatest crude protein yield, followed by Akela, Ramon, Velox, and Hallayuchae. As seeding rate increased, crude protein content linearly increased but crude fiber content linearly decreased. The forage cultivars had higher crude protein and lower crude fiber than the oilseed cultivar Hallayuchae. Our results demonstrate that Sparta was the best adapted cultivar to Cheju area and the optimum seeding rate for Sparta was about 10 kg/ha.

• 한국축산시설환경학회지
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• 제14권1호
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• pp.1-8
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• 2008

This study was conducted to solve the problem of public grievance owing to odor of a pig farm. Odor emissions from pig production systems mainly originate from liquid manure storage and solid manure fermentation. The low-cost odor abatement system (OAS) for application at liquid manure storage tank and solid manure fermentation facilities was developed in this study. The OAS adapted odor removing principles of a biofilter and biotrickling filter. The OAS is very simplified in structure. The appearance of the OAS had a form of cylindrical or cubical shape. The system performance was monitored for about one year after stabilization. A 7 seconds empty bed contact time for the OAS was adapted to achieve the odor reduction levels. The commercial type of OAS was constructed with media comprised of wood chips. Moisture content always remained above 50% wet basis. Average ammonia removal efficiency for the developed design was 89% at the liquid manure storage tank. Also, the removal efficiency at a solid manure fermentation facility was 86% on ammonia.

• 미생물학회지
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• 제52권3호
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• pp.388-390
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• 2016

부식산(humic acid)을 이용하여 저온에서 배양된 Pedobacter sp. PAMC 27299는 남극 바톤 반도(Barton Peninsula) King George Island의 해안가 이끼(moss debris)로부터 분리되었다. 본 연구에서는 Pedobacter sp. PAMC 27299의 유전체 서열을 해독하였으며 크기 6,147,290 bp, G+C 함량 40.54%의 PAMC 27299는 지구 온난화 관련 저온적응 부식산 분해 효소를 보유하는 것으로 확인되었다.

• 방송공학회논문지
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• 제8권4호
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• pp.339-350
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• 2003

The Part 7 of MPEG-21, called Digital Item Adaptation, aims at an interoperable transparent access of multimedia contents in heterogeneous environments. This standard facilitates the development of Universal Multimedia Access (UMA) systems, which adapt the rich multimedia contents to provide user the best possible presentation under the constraints of various terminals and network connections. Content adaptation has two major aspects: one is modality conversion that converts content from one modality (e.g. video) to different modalities (e.g. image) the other is content scaling that changes the titrates (or qualities) of the contents without converting their modalities. At the output of adaptation process, the highly-subjective qualities of adapted contents nay vary widely with respect to point-of-views of different providers and different users. So, user should have some control on the adaptation process. In this paper, we describe two description tools of user characteristics, the presentation priority preference and the modality conversion preference, which allow user to have flexible choices on the qualities and modalities of output contents. We also present a systematic approach to integrate these user preferences into the adaptation process. These description tools are developed in the process of MPEG-21 standardization.

• 한국작물학회지
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• 제43권4호
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• pp.245-249
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• 1998

Soybean [Glycine max (L.) Merr.), mungbean [Vigna radiata (L.) Wilcz.], cowpea [V. unguiculata (L.) Walp.], adzuki bean [V. angularis (Willd.) Ohwi & Ohashi], maize [Zea mays L.], sorghum [Sorghum bicolor (L.) Moench], sorghum $\times$ sudangrass [So bicolor intraspecific hybrid], and Japanese millet [Echinochloa crusgalli var. frumentacea (Link) W.F. Wight] were grown at two planting dates (18 June and 15 July) at Cheju in 1997 to select the best forage legumes adapted to Cheju Island for grass-legume forage rotation. Averaged across planting dates and cultivars, dry matter (DM), crude protein (CP), and total digestible nutrient (TDN) yields were 5,646, 1,056, and 3,637 kg/ha for soybean, 4,458, 676, and 2,661 kg/ha for mungbean, 3,289, 553, and 2,055 kg/ha for cowpea, 3,931, 674, and 2,489 kg/ha for adzuki bean, 12,695, 969, and 7,642 kg/ha for maize, 17,071, 1,260, and 8,857 kg/ha for sorghum, 16,355, 1,163, and 8,543 kg/ha for sorghum $\times$ sudangrass hybrid, and 8,288, 929, and 4,091 kg/ha for Japanese millet. Soybean was higher in CP, ether extract (EE), and TON content but was lower in nitrogen free extract content compared with the three other legumes. The legumes had much higher CP (13.7 to 21.9%), EE (2.42 to 6.23%), and TDN (58.7 to 69.9%) content but lower in crude fiber (CF) content (17.3 to 25.3%) than did the grasses tested except maize which had relatively lower CF content but higher TDN content. These results suggest that soybean could be the best forage legume for grass-legume forage rotation in the Cheju region.

• 한국작물학회지
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• 제10권
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• pp.57-60
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• 1971

한국산 소맥 5품종과 미국산소맥 3품종을 밀과 밀가루의 성분ㆍ회분ㆍ조단백질함량 및 제분율을 조사하였는데 그 성적을 요약하면 다음과 같다. 1. 수분은 한국산밀이 미국산밀보다 품종과 시료에 따른 차가 컸다. 2. 밀의 회분함량이 미국산 밀에서는 경질과 연질에 따라 차가 현저했는데 한국산밀에서는 그렇지 않았다. 3. 제분율은 한국밀중에서는 육성 003 한 품종만이 비교적 높고 기타는 미국밀에 비하여 현저히 낮았다. 4. 밀가루의 회분함량은 품종간의 차를 인정할수 없었다. 5. 밀가루의 조단백질함량은 한국밀보다 미국밀중에 현저히 높은 것이 있었다. 6. 밀의 조단백질함량과 밀가루의 조단백질함량과의 상관은 한국밀에서 보다 미국밀에서 현저하게 높았다.