• Title/Summary/Keyword: $F_1$ Hybrid

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A study on synthesis and mechanical properties polyurethane-acrylic hybrid resin with milk casein (Milk casein을 이용한 수용성 polyurethane-acrylic hybrid resin의 합성 및 물성 영향에 관한 연구)

  • Lee, Joo-Youb;Nam, Sang-Sung
    • Journal of the Korean Applied Science and Technology
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    • v.30 no.3
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    • pp.567-574
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    • 2013
  • For this research, prepared water soluble milk casein resin and waterborne polyurethane-acrylic resin. Use these resin, this article has been analyzed about change of mechanical properties by increasing amount of casein resin in polyurethane-acrylic resin on coated leather. According to measure data for solvent resistance, WPA(waterborne polyurethane-acrylic resin) resin and WPA-C1, C2, C3(samples of polyurethane-acrylic resin with milk casein resin) had good property. As known in the results, increase of casein constant did not influence to big change of hybrid resin properties. As test of tensile strength, WPA had lowest tensile characteristic(1.598 $kg_f/mm^2$) and WPA-C3 had highest tensile characteristic(1.718 $kg_f/mm^2$). Also best properties of abrasion was WPA-C3(06.021 mg.loss). In elongation case, WPA had best properties(754 %) in this experiment.

Development of Tobacco Mosaic Virus (TMV) resistant Flue-cured $\textrm{F}_1$ Hybrid, KF118

  • Chung, Yun-Hwa;Keum, Wan-Soo;Park, Sang-Ju;Jung, Suk-Hum;Kim, Yong-Am;Kang, Yue-Gyu;Chung, Youl-Young;Cho, Soo-Heon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.5
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    • pp.388-391
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    • 2003
  • Tobacco mosaic virus (TMV), TMV-common strain, causes severe damage at growth, yield and leaf quality on flue-cured tobacco in Korea. Controlling TMV outbreak with cultivating practices and chemicals are limited, thus, the best way would be developing TMV resistant variety. A new flue-cured hybrid, KF118, was developed from a cross of maternal parent MSTC175 and TC853 at the Agro-tech. Research Group, KT&G Central Research Institute. KF118 exhibited more vigorous growth characteristics in early stage than that of NC82, standard variety in Korea, while other characters were favorable to those of NC82, It is highly resistant to TMV and bacterial wilt(Ral-stonia solanacerum), and black shank(phytophthora parasitica var. nicotianae) is comparable to that of NC82. It should adapt well to the flue-cured production area, and can reduce premature flowering under unfavorable weather conditions. Yield of KF118 is 1 to 2% higher, and leaf quality is 4% higher than NC82. Fl hybrid, KF118, met acceptable standards for chemical and physical characteristics of cured leaf, and ranked high in good smoking taste by panel members in KT&G.

A Study on Combustion Characteristics of Hybrid Rocket with the Variation of L/D Ratio (하이브리드 로켓의 L/D 비 변화에 따른 연소특성 연구)

  • Kim Soo-Jong;Kim Jin-Kon;Lee Seung-Chul;You Woo-Jun;Lee Jung-Pyo
    • Journal of the Korean Society of Propulsion Engineers
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    • v.9 no.4
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    • pp.31-38
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    • 2005
  • In this paper, the combustion characteristics of a hybrid propulsion system were studied with various L/D(length vs diameter) ratio of the single po.1 type solid fuel. Experiments were performed for 2 cases with the fixed grain port diameter and fuel length respectively. For the first case, results show that there are no large variations for regression rates as the L/D ratio changes. And as the L/D ratio increases, the O/F ratio decreases and thrust, characteristic velocity tends to increase. For the second case, there is no large change for O/F ratio, thrust and characteristic velocity as L/D ratio changes. On the other hand, as the L/D ratio decreases, only the regression rate tends to increase. Experimentally, exponent n in $\dot{r}=a{G_0}^n$ was found about 0.5 and then the O/F ratio was shown nearly constant. In the experiment, PE and gas oxygen were used as a fuel and an oxidizer.

Studies on the Production of $F_1$ Hybrid Seed, Using Male Sterile Flue-cured Tobacco(Nicotiana Tabacum L.) I . Effects of the mixed rates of pollen diluent dusts on the F$_1$ hybrid seeds production. (황색종 담배에 있어서 웅성불임 $F_1$ 품종의 종자 생산에 관한 연구 I. 화분과 증량제의 배합비율이 종자 생산성에 미치는 영향)

  • 신승구
    • Journal of the Korean Society of Tobacco Science
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    • v.20 no.2
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    • pp.166-171
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    • 1998
  • In order to improve the efficiency of F$_1$ hybrid seeds production(KF 114), some experiments were carried out in a greenhouse this year. Mother plant(MSNC567) and pollen plant(NC) were grown in some pots (30 x 30cm, WxH). The gathered pollens were mixed with celite, pollen deluent dusts and stored in refrigerator at l$0^{\circ}C$ before pollination. To establish the critical range of the mixed rate and the storage period of pollens, the change in a percent of capsule set, number of seed and seed weight per capsule, weight of 1000 seeds and germination percent of seed resulted of pollination with pollen deluent dusts were investigated. The results are as follows; Percent of capsule set showed the mixed rate 1:5 resulted in no difference and those of 1:10 and 1:20 decreased about 5 ~15% when compared with trials using pollen alone. There was no difference among duration of storage in a same mixed rate. Numbers of seed per capsule showed a significant difference among the mixed rates and among durations of storage. Numbers of seed per capsule were decreased about 55 ~ 90 % as the mixed rate increase, about 2 ~ 28 % as the duration of storage increase. Weight of seed per capsule decreased about 16 ~ 23 % as the duration increase and decreased about 3 ~ 89 % as the mixed rate increase when compared with trials using pollen alone. Weight of 1000 seeds showed non significant difference among duration of storage but were higher than trials used pollen alone as the mixed rate increase.

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Fabrication of Fiber/Particle Hybrid MMCs and Analysis of the Mechanical Properties (섬유/입자 혼합 금속복합재료의 제조 및 특성평가)

  • 정성욱;남현욱;정창규;한경섭
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2001.05a
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    • pp.34-37
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    • 2001
  • This study developed Fiber/Particle Hybrid MMCs and analyzed their mechanical properties. Using $\textrm{Al}_2\textrm{O}_3f$ and $\textrm{Al}_2\textrm{O}_3p$ with the fiber to particle ratio of 1:1, 1:3, 1:5 hybrid preform and MMCs are fabricated. For the analysis of the mechanical properties, three point bending tests were preformed for the preform and tensile test for the MMCs. The experimental results show that the hybrid MMCs can be successfully fabricated using the equipment of fiber preform fabrication system and squeeze casting method. And as the amount of particle in hybrid MMCs increases, the tensile strength, elastic modulus and the volume fraction of reinforcement increases.

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High frequency somatic embryogenesis and plant regeneration of interspecific ginseng hybrid between Panax ginseng and Panax quinquefolius

  • Kim, Jong Youn;Adhikari, Prakash Babu;Ahn, Chang Ho;Kim, Dong Hwi;Kim, Young Chang;Han, Jung Yeon;Kondeti, Subramanyam;Choi, Yong Eui
    • Journal of Ginseng Research
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    • v.43 no.1
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    • pp.38-48
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    • 2019
  • Background: Interspecific ginseng hybrid, Panax ginseng ${\times}$ Panax quenquifolius (Pgq) has vigorous growth and produces larger roots than its parents. However, F1 progenies are complete male sterile. Plant tissue culture technology can circumvent the issue and propagate the hybrid. Methods: Murashige and Skoog (MS) medium with different concentrations (0, 2, 4, and 6 mg/L) of 2,4-dichlorophenoxyacetic acid (2,4-D) was used for callus induction and somatic embryogenesis (SE). The embryos, after culturing on $GA_3$ supplemented medium, were transferred to hormone free 1/2 Schenk and Hildebrandt (SH) medium. The developed taproots with dormant buds were treated with $GA_3$ to break the bud dormancy, and transferred to soil. Hybrid Pgq plants were verified by random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR) analyses and by LC-IT-TOF-MS. Results: We conducted a comparative study of somatic embryogenesis (SE) in Pgq and its parents, and attempted to establish the soil transfer of in vitro propagated Pgq tap roots. The Pgq explants showed higher rate of embryogenesis (~56% at 2 mg/L 2,4-D concentration) as well as higher number of embryos per explants (~7 at the same 2,4-D concentration) compared to its either parents. The germinated embryos, after culturing on $GA_3$ supplemented medium, were transferred to hormone free 1/2 SH medium to support the continued growth and kept until nutrient depletion induced senescence (NuDIS) of leaf defoliation occurred (4 months). By that time, thickened tap roots with well-developed lateral roots and dormant buds were obtained. All Pgq tap roots pretreated with 20 mg/L $GA_3$ for at least a week produced new shoots after soil transfer. We selected the discriminatory RAPD and ISSR markers to find the interspecific ginseng hybrid among its parents. The $F_1$ hybrid (Pgq) contained species specific 2 ginsenosides (ginsenoside Rf in P. ginseng and pseudoginsenosides $F_{11}$ in P. quinquefolius), and higher amount of other ginsenosides than its parents. Conclusion: Micropropagation of interspecific hybrid ginseng can give an opportunity for continuous production of plants.

Slim Mobile Lens Design Using a Hybrid Refractive/Diffractive Lens (굴절/회절 하이브리드 렌즈 적용 슬림 모바일 렌즈 설계)

  • Park, Yong Chul;Joo, Ji Yong;Lee, Jun Ho
    • Korean Journal of Optics and Photonics
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    • v.31 no.6
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    • pp.281-289
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    • 2020
  • This paper reports a slim mobile lens design using a hybrid refractive/diffractive optical element. Conventionally a wide field of view (FOV) camera-lens design adopts a retrofocus type having a negative (-) lens at the forefront, so that it improves in imaging performance over the wide FOV, but with the sacrifice of longer total track length (TTL). However, we chose a telephoto type as a baseline design layout having a positive (+) lens at the forefront, to achieving slimness, based on the specification analysis of 23 reported optical designs. Following preliminary optimization of a baseline design and aberration analysis based on Zernike-polynomial decomposition, we applied a hybrid refractive/diffractive element to effectively reduce the residual chromatic spherical aberration. The optimized optical design consists of 6 optical elements, including one hybrid element. It results in a very slim telephoto ratio of 1.7, having an f-number of 2.0, FOV of 90°, effective focal length of 2.23 mm, and TTL of 3.7 mm. Compared to a comparable conventional lens design with no hybrid elements, the hybrid design improved the value of the modulation transfer function (MTF) at a spatial frequency of 180 cycles/mm from 63% to 71-73% at zero field (0 F), and about 2-3% at 0.5, 0.7, and 0.9 fields. It was also found that a design with a hybrid lens with only two diffraction zones at the stop achieved the same performance improvement.

Use of Microsatellite Markers to Identify Commercial Melon Cultivars and for Hybrid Seed Purity Testing (Microsatellite Marker를 이용한 멜론 시판품종의 품종식별과 F1 순도검정)

  • Kwon, Yong-Sham;Hong, Jee-Hwa
    • Horticultural Science & Technology
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    • v.32 no.4
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    • pp.525-534
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    • 2014
  • Microsatellite markers were used to identify 58 major commercial melon cultivars, and to assess hybrid seed purity of a melon breeding line known as '10H08'. A set of 412 microsatellite primer pairs were utilized for fingerprinting of the melon cultivars. Twenty-nine markers showed hyper-variability and could discriminate all cultivars on the basis of marker genotypes, representing the genetic variation within varietal groups. Cluster analysis based on Jaccard's distance coefficients using the UPGMA algorithm categorized 2 major groups, which were in accordance to morphological traits. The DNA bulks of female and male parents of breeding line '10H08' were tested with 29 primer pairs based on microsatellites to investigate purity testing of $F_1$ hybrid seeds, and 5 primer pairs exhibited polymorphism. One microsatellite primer pair (CMGAN12) produced unambiguous polymorphic bands among the parents. Among 192 seeds tested with CMGAN12, progeny possibly generated by self-pollination of the female parent were clearly distinguished from the hybrid progeny. These markers will be useful for fingerprinting melon cultivars and can help private seed companies to improve melon seed purity.

Korean Entity Linking based on KorBERT and Popularity (KorBERT와 Popularity 정보에 기반한 한국어 개체연결 )

  • Jeong Heo;Kyung-Man Bae;Soo-Jong Lim
    • Annual Conference on Human and Language Technology
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    • 2022.10a
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    • pp.502-506
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    • 2022
  • 본 논문에서는 KorBERT와 개체 인기정보(popularity)를 이용한 개체연결 기술을 소개한다. 멘션인식(mention detection)은 KorBERT를 이용한 토큰분류 문제로 학습하여 모델을 구성하였고, 개체 모호성해소(entity disambiguation)는 멘션 컨텍스트와 개체후보 컨텍스트 간의 의미적 연관성에 대한 KorBERT기반 이진분류 문제로 학습하여 모델을 구성하였다. 개체 인기정보는 위키피디아의 hyperlink, inlink, length 정보를 활용하였다. 멘션인식은 ETRI 개체명 인식기를 이용한 모델과 비교하였을 경우, ETRI 평가데이터에서는 F1 0.0312, 국립국어원 평가데이터에서는 F1 0.1106의 성능 개선이 있었다. 개체 모호성해소는 KorBERT 모델과 Popularity 모델을 혼용한 모델(hybrid)에서 가장 우수한 성능을 보였다. ETRI 평가데이터에서는 Hybrid 모델에서의 개체 모호성 해소의 성능이 Acc. 0.8911 이고, 국립국어원 평가데이터에서는 Acc. 0.793 이였다. 최종적으로 멘션인식 모델과 개체 모호성해소 모델을 통합한 개체연결 성능은 ETRI 평가데이터에서는 F1 0.7617 이고, 국립국어원 평가데이터에서는 F1 0.6784 였다.

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