• 한국주조공학회지
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• 제31권6호
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• pp.347-353
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• 2011

There is thixo-extrusion to form high strength aluminum alloy. But, it is a problem that grains become grain coarsening during reheating process because the alloy was exposed at high temperature. In order to solve grain growth during reheating process, calcium was added in Al-Zn-Mg alloys. Primary a grain sizes of semi-solid Al-Zn-Mg-(0, 0.4, 0.6 and 0.9, wt.%)Ca were measured with image analyzer after reheating. Measured primary a grain sizes were applied to LSW(Lifshitz-Slyozov and Wagner) equation to check the effect of Ca on grain coarsening. Coarsening rate constant K values of semi-solid Al-Zn-Mg-(0, 0.4, 0.6 and 0.9, wt.%)Ca alloys were $371\;mm^3s^{-1}$, $247\;mm^3s^{-1}$, $198\;mm^3s^{-1}$ and $166 mm^3s^{-1}$, respectively. As increasing calcium content, K value decreased which means grains are refined. Also, grains of calcium addition were more spherical than that of calcium free.

• 농업과학연구
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• 제40권4호
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• pp.311-316
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• 2013

This study was conducted to evaluate the efficacy of two different formulations and application timings of benzobicyclon+penoxsulam+pyrzaosulfuron-ethyl (BPP) in rice field. BPP granule (GR) and tablet (TB) controlled more than 90% of four weed species 10 and 15 days after sowing in direct seeding when compared with untreated control. BPP TB was highly effective to control herbicide resistant Scirpus juncoides and Monochoria vaginalis both 10 and 15 days after transplanting (DAT). BPP GR controlled 94.0 and 96.5% of S. juncoides and M. vaginalis, respectively 10 DAT, but its efficacy decreased to 88.5 and 49.8% respectively 15 DAT. When compared with untreated control, no visual injuries were detected at 255 and 510 g a.i./ha of BPP. The yield of rice increased in both BPP GR and TB in transplanting and direct seeding rice cultivation when compared with untreated control. Based on these data, early application (10 DAT) of BPP GR and TB can be applied to provide effective weed control, especially in the field infested with herbicide resistant weed species.

• Weed & Turfgrass Science
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• 제3권2호
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• pp.110-113
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• 2014

The continuous use of acetolactate synthase (ALS) and acetyl-CoA carboxylase (ACCase) inhibitors has led to the selection of herbicide resistant barnyardgrass populations in direct-seeded rice fields of Korea. This study was conducted to identify herbicide resistant barnyardgrass biotypes and to determine the cross- and multiple-resistance of them. 25% of the population collected from Taeahn was partially resistant to ACCase inhibitors and 22% collected from Kimjae were partially resistant to ALS inhibitors. However, 8.2% of the population from both sites was resistant to ALS and ACCase inhibitors. Resistance to sulfonylurea herbicide, flazasulfuron was identified from two barnyardgrass accessions collected from both Taeahn and Kimjae. One barnyardgrass accession from both sites was resistant to ACCase inhibitor, sethoxydim. The cross-resistance to ALS inhibitors was identified at one barnyardgrass accession from Taeahn and at two accessions from Kimjae. Further, crossresistance to ACCase inhibitors was also identified at barnyardgrass accessions from Taeahn and Kimjae. Multiple-resistance to flazasulfuron and sethoxydim was determined at four barnyardgrass accessions from Taeahn and at six accessions from Kimjae. Therefore, the herbicide mixture and sequences within a growing season or the herbicide rotation with different modes of actions across growing seasons are recommended to control herbicide-resistant barnyardgrass in infested fields.

• 한국멀티미디어학회지
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• 제14권4호
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• pp.88-98
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• 2010

지금은 급속도로 발전하는 ICT(정보통신기술)뿐만 아니라 BT, CT, NT, ST 들이 컨버전스하는 고도의 통합기술이 활용되는 유비쿼터스시대이다. 이들 기술로 시간과 공간의 벽을 넘어 인간의 5감을 크게 도와주는 3차원 가상현실 시각화기술을 이해함은 최근에 매우 중요하게 되었다. 본 연구는 3차원 가상현실 시각화 기술을 살피고 향후의 발전 방향을 예측하고 전망과 제언을 하는 것이다. 가상현실 구현기술은 3차원 컴퓨터그래픽스 표현기술에 크게 종속되어 있어 몰입할 수 있는 3차원 영상 구현기술이 가능하였고, 또한 컴퓨터의 상호작용성을 이용하여 새로운 패러다임으로 영상을 증강시키는 PC와 디스플레이 장비를 기반으로 구현되고 있으며, 보다 인간성을 강조하는 방향으로 활발히 연구되고 있다. 이 기술은 초고속 인터넷 기술 등의 상위기술들의 해결로 명실상부한 21세기 유비쿼터스사회 구현에 큰 몫을 감당할 것이 확실하다.

• 복식
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• 제33권
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• pp.189-199
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• 1997

The following contents are the results from the examination of unisex fetishism minimal and active which are Mods look. Unisex-becasue of the changing in musician and the role of sex Mods girl adopted much from men's clothing. The unisex mods look expressed in the 1990s is not the expression confronting the estab-lished value and the confusion of sex as it did in the '60s but possibly the appearance of a fashion trend. Fetishism-in the '60s the Mods look changed mens clothing into more wonman-like clothing which expressed their internal and external values of thinking. this fetishism phenomenon is also strongly expressed among the in the 1990s. This gives a future-orientid feeling by expressing with a modern sense the 60's fetish dress which used woman-like silhouettes bright and stretch fabric colorful and vivid tone. Minimal-The 60's Mods put on mini skirts called the revolution of length as a mode of re-sistance and mininmal dress as a way of ex-pressing the liberation of body and the con-sciousness of beauty. Minimal is reflected well on slim and fit jackets and pants and short and fit pants etc. mods look in the '90s also consists of the general trend of slim and fit silhouette. Active-Mods that reject the value of estab-lished generation in the 60s showed a sporty and casual trend on fashion. Mods works around clubs wore polo shirts and cadigan and Mods enjoys scooter often wore anorak parkas This active style of Mods approched to the young' casual with freshness expressing newly in the '90s polo shirts took a seat as an item of street fashion especially in the beginning of 1996. Mods in the 1960s shows well a fashion flow of the age as a street fashion which expresses the mental world reflected in politics econo-mics society and culture within the people of the age. These Mods looks revived in the early 1990's awaken an importance of the culture of the young as the cultural qualities included in Mods of the past life and this fashion trend expected to take a part as a symbol of fashion culture.

• Molecules and Cells
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• 제39권3호
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• pp.250-257
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• 2016

Abiotic stresses such as drought and low temperature critically restrict plant growth, reproduction, and productivity. Higher plants have developed various defense strategies against these unfavorable conditions. CaPUB1 (Capsicum annuum Putative U-box protein 1) is a hot pepper U-box E3 Ub ligase. Transgenic Arabidopsis plants that constitutively expressed CaPUB1 exhibited drought-sensitive phenotypes, suggesting that it functions as a negative regulator of the drought stress response. In this study, CaPUB1 was over-expressed in rice (Oryza sativa L.), and the phenotypic properties of transgenic rice plants were examined in terms of their drought and cold stress tolerance. Ubi:CaPUB1 T3 transgenic rice plants displayed phenotypes hypersensitive to dehydration, suggesting that its role in the negative regulation of drought stress response is conserved in dicot Arabidopsis and monocot rice plants. In contrast, Ubi:CaPUB1 progeny exhibited phenotypes markedly tolerant to prolonged low temperature ($4^{\circ}C$) treatment, compared to those of wild-type plants, as determined by survival rates, electrolyte leakage, and total chlorophyll content. Cold stress-induced marker genes, including DREB1A, DREB1B, DREB1C, and Cytochrome P450, were more up-regulated by cold treatment in Ubi:CaPUB1 plants than in wild-type plants. These results suggest that CaPUB1 serves as both a negative regulator of the drought stress response and a positive regulator of the cold stress response in transgenic rice plants. This raises the possibility that CaPUB1 participates in the cross-talk between drought and low-temperature signaling pathways.

• 농업과학연구
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• 제42권2호
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• pp.111-116
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• 2015

Combined applications of rice bran with pine leaves were tested to examine the inhibitory effects to paddy weeds and increased yield of rice for developing techniques of environment-friendly weed management in paddy rice fields. Weed control efficacy at 60 days after treatment was improved to 88.8% by combined application of rice bran with pine leaves, while weed control efficacy by single application of rice bran showed 67.5%. The other weed control efficacy combined with chestnut leaves and barley straws were 76.3% and 69.9% respectively. Combined application of rice bran with pine leaves was more effective to broadleaf weeds such as Monochoria vaginalis. Weed control efficacy by combined application with pine leaves was 100% until 70 days after rice transplanting and maintained weed control effect up to 90 days after transplanting. Rice yield by combined application of rice bran with pine leaves was 526 kg/10 a, which was higher yield than by combined application with barley straws, single application of rice bran, natural snail application and hand weeding.

• 에너지공학
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• 제22권3호
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• pp.250-261
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• 2013

현대 사회에서 우리는 주로 화석 연료 인프라 위에 구축된 화석 연료 경제 시대에 살고 있다. 그 결과 발생하는 에너지 도전문제(예: 화석 연료의 자원 고갈 문제, 환경 오염 문제, 에너지 안보 문제)로 지속가능 발전은 한계에 부딪히고 있는 실정이다. 이들 도전문제를 극복하기 위해 기존 석유-기반 리파이너리, 즉 석유 정제(ORF) 역할을 대체할 바이오에너지(예: 바이오연료, 전기, 열) 및 바이오케미컬 (예: C5 계열, C6 계열) 동시-생산 시스템으로 바이오매스를 사용한 바이오리파이너리(BRF) 개념이 새롭게 출현하였다. 이는 석유 경제에서 바이오경제로 패러다임 천이(shift)가 진행되고 있음을 가리키는 지표(indicator)가 된다. 이러한 바이오매스-기반 경제는 현재 구축되어 있는 ORF 인프라를 거의 변경 없이 그대로 활용할 수 있는 높은 호환성, 적은 폐기물 발생량, 이산화탄소 중성적 친환경성, 지역 농업/임업 경제 활성화 등과 같은 매력적인 강점들을 갖고 있다. 무엇보다도 석유 자원 빈곤국이 고 석유 수입국이며 ORF 인프라를 이미 구축한 우리나라에서는 에너지 안보 및 지속가능 발전 측면에서 고가치 BRF 시스템의 연구 개발 및 기술 사업화에 국가적 차원에서 아낌없이 투자와 지원을 제공해야 할 필요성이 높아지고 있다. 이 연구에서는 바이오에너지/바이오케미컬 동시-생산용 시스템으로 활용될 BRF 기술의 국내외 동향을 소개하고자 한다.

• 한국잡초학회지
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• 제31권1호
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• pp.8-23
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• 2011

유기농 재배에서 이용되고 있는 잡초방제 기술 및 연구 동향을 검토하고 앞으로 방향을 제시하기 위하여 화학적 방제를 배제하고 기계적 방제, 경종적 방제, 생물적 방제를 포함한 종합방제 기술에 대한 문헌을 정리하고 분석하여 유기농업에서의 새로운 잡초 관리방안을 전망하고자 하였다. 물리적 방법은 기계적 방법, 열, 광선, 전기충격, 압축공기, 로봇잡초방제기술, 그리고 경종적 방법은 멀칭, 경운, 윤작, 피복식물, 경합을 이용한 방법이 포함된다. 생물적 방제는 미생물제초제, 대량증식 생물제제, 광역 생물제제, 상호대립억제물질 등이 개발되거나 또는 이용되고 있다. 유기농재배에서 성공적인 잡초방제를 위하여 물리적 방법과 경종적 방법은 제초제 사용이 제한된 조건에서 가장 중요한 잡초방제 수단이므로 기계적, 경종적 방법을 근간으로 하고 생물적 방법이 조화롭게 보완되는 종합잡초관리방법이 요구된다. 그리고 유기농 재배에서 수익을 창출하고 적합한 장기적 잡초관리 방안을 도출하기 위하여 잡초관리 결정에 도움이 되는 모델의 개발도 필요하다.

• 농업과학연구
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• 제45권4호
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• pp.583-590
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• 2018

Genus Typha L. (Typhaceae; Cattail in common) is one of the hydrophytic plants found in semi-aquatic regions. About nine to 18 species of the genus exist all over the world. In Korea, the most commonly found cattail species are T. laxmanni and T. angustifolia. The aim of this study was to prepare a cDNA library and sequences and analyze expressed sequence tags (ESTs) from these species, T. laxmanni and T. angustifolia. In the case of T. laxmanni, we observed that 715 out of 742 ESTs had high quality sequences, whereas the remaining 27 ESTs were low quality sequences. In this study, we identified 77 contigs, 393 unassembled clones and 65.7% singletons. Furthermore, in the case of T. angustifolia, we recorded 992 high quality EST sequences, and by excluding 28 low quality sequences from among them, we retrieved 120 contigs, 348 unassembled clones and 48.9% singletons. The basic local alignment search tool (BLAST) and Kyoto encyclopedia of genes and genomes (KEGG) database results enabled us to identify the functional categories, i.e., molecular function (16.5%), biological process (22.2%) and cellular components (61.3%). In addition, between these two species, the no hits and anonymous genes were 4.2% and 11.7% and 6.2% and 11.2% in T. laxmanni and T. angustifolia, respectively, based on the BLAST results. The study concluded that they have certain species-specific genes. Hence, the results of this study on these two species could be a valuable resource for further studies.