• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.347-352
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• 2003

This work was undertaken to study the effect of stigmatic and cut-style pollination on self seed set in Lilium longiflorum and L. ${\times}$ formolongi, and their crosses as the female parent with other cultivars/genotypes. Stigmatic pollination of L. longiflorum cv. Gelria and Lorina resulted in cent per cent fruit set with mean number of seeds/fruit of 189 and 70, respectively. However, cut-style pollination resulted in 87％ and 40％ fruit set in Gelria and Lorina, respectively. The corresponding mean number of seeds/fruit was 53 and 20. In L. ${\times}$ formolongi, stigmatic pollination set 80％ fruits with 736 seeds/fruit. On the other hand, cut-style pollination resulted in 47％ fruit set with 81 seeds/fruit. The intraspecific stigmatic pollination of L. longiflorum cv. Gelria and Lorina with other cultivars formed 60％ fruits with a mean number of 18 seeds/fruit. However, only 20％ fruit set with mean number of seeds/fruit of 7 was recorded when cut-style pollination of L. longiflorum cultivar were pollinated with other cultivars/genotypes. In the intraspecific pollination of L. ${\times}$ formolongi cv. Raizan with Novia, fruit set resulting from stigmatic and cut-style pollination was 75％ and 50％, respectively with the corresponding mean number of seeds/fruit of 579 and 98. It was concluded that self as well as intraspecific seed set in the two species of Lilium gets considerably reduced as a result of cut-style pollination.

• Korean Journal of Plant Resources
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• v.14 no.2
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• pp.163-168
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• 2001

This study was conducted to obtain basic information on cross breeding for developing bolting resistant variety of Angelica gigas NAKAI which has been subjected to severe yield reduction resulted from flower-stalk initiation during the growth. Compatibility of selfing and/or crossing pollination among 5 local cultivars were tested. Results obtained are summarized as follows. In case of three year old plant, all cultivars emerged March 14 and bolted from May 12 to May 13. Ponghwa cultivar was flowered 3 to 5 days earlier than other cultivars. Flower duration continued 41 to 43 days. Interval of flowering date from main stem to first primary branch, from first to second or second to third primary branch was 9 to 13 days. Emergency of stamen proceeded 4~8 days of pistil initiation demonstrating that Angelica gigas NAKAI is protandrous plant. Furthermore initiation of first pistil was 1~4days later than formation of last stamen in the same flower cluster. Percent pollination of Angelica gigas NAKAI was 52% under natural condition, so called open-pollination, but bagging by enveloping flowers was as low as 0.4~2.4%. In the result of compatibility test, all local cultivars tend to show both of self-and cross-compatibility. Inpollination, ‘Muju’$\times$‘Muju’combination showed highest fertility up to 40.8% whereases cross pollination, ‘Pyeongchang’$\times$‘Inje’combination, showed 67.0% fertility.

• Journal of Adhesion and Interface
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• v.23 no.1
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• pp.8-16
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• 2022

In this study, self-healable waterborne polyurethane (SH-WPU) as shoes and coating materials with self-healable disulfide functionalities was synthesized by mixing polyether polyol to impart excellent durability and heat resistance and polycarbonate polyol to impart excellent mechanical properties. The synthesized SH-WPU was characterized by fourier transform-infrared spectroscopy (FT-IR), and physical and self-healing properties were confirmed through universal testing machine (UTM) and scanning electron microscope (SEM) measurements. Tensile strength and hardness were increased and elongation was decreased by using polycarbonate polyol. In addition, as a result of comparison of thermal properties, thermal stability has been increased as the content of polycarbonate polyol increased. The healing efficiency showed the highest efficiency when poly(tetramethylene ether)glycol : polycarbonate polyol = 0.75 : 0.25, and it was confirmed that the damaged part was healed through surface observation using a microscope and SEM.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.65-71
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• 1997

The energy supplied by motor of extruder, being known mostly to be dissipated as heat, was classified into two kinds of energy: a thermal energy by heat dissipation and a purely mechanical energy. The thermal energy was defined as a energy in terms of temperature rise and the mechanical energy as the motor energy minus the heat dissipated energy. A method to derive the thermal energy and the relative mechanical energy (the mechanical energy calculated regarding the mechanical energy at the lowest screw speed as zero) under the condition of constant barrel temperature was developed by which an extrusion case was analyzed. When extruding com grits with moisture $(27{\sim}37%)$ at low barrel temperature $({\leq}80^{\circ}C)$, the thermal energy slightly increased with increase in the moisture content, whereas the relative mechanical energy increased to a great extent. When increasing the screw speed, the thermal energy was nearly kept constant, whereas the relative mechanical energy largely varied. It is concluded that as the moisture content increases, the role of the mechanical energy becomes more effective than the heat energy dissipated from the motor energy.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.72-76
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• 1997

The effect of the energy supplied in extrusion on the starch gelatinization was analyzed. The energy needed for extrusion is generated by motor and heater. The motor energy is transformed into a thermal energy by heat dissipation and a mechanical energy, and the heater energy is of a thermal energy. At the low barrel temperature $({\leq}80^{\circ}C)$, it was found out there are two kinds of thermal energy by heat dissipation: one by a powder friction of corn grit with low moisture contents and the other by a viscous dissipation of corn grit with high moisture contents. The dissipated thermal energy by the powder friction was more effective on the starch gelatinization than that by the viscous dissipation. The effect of the mechanical energy was also analyzed in terms of a relative mechanical energy. The gelatinization of corn grit with high moisture contents $({\geq}33%)$ largely depended on the change in the relative mechanical energy, whereas that with low moisture contents $({\leq}30%)$ hardly depended on it.

• Horticultural Science & Technology
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• v.19 no.3
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• pp.373-377
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• 2001

This study was conducted to find optimum pollination methods for overcoming pre-fertilization incompatibility in interspecific crosses between L. longiflorum 'Gelria' (LG) and L. cernuum (LC). In cross combination of $LC{\times}LG$, the survival rate of the ovaries was higher in the cut style pollinations than in normal stigmatic pollination. Among the various cut style pollination methods, pollination after cutting the styles 2 3mm length above the ovary and top of the ovary were the most effective ones. No ovaries and ovules survived in cross pollination of $LC{\times}LG$. In self-pollination of LG and cross pollination of $LC{\times}LG$, pollens germinated on the stigma by 12 hours and reached to the ovules by 90 hours after pollination. However, in the cross pollination of $LC{\times}LG$, pollen tubes elongated very slowly until 48 hours after pollination and a lot of deformed tubes were observed in the styler canal having swelled tube tip and irregular heavy callose deposition. The pollination time after anthesis also affected on the survival rate of ovaries and ovules showing the best result when pollinated on three days after anthesis. Stigma exudate promoted slightly the enlargement of ovaries, but the survival rate of ovaries and ovules was not increased.

• Korean Journal of Plant Resources
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• v.3 no.2
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• pp.123-128
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• 1990

In every reciprocal crosses of self pollination, interspecific pollination through ordinary stigma pollination of L. longiflorum and $L.{\;}{\times}{\;}elegans$, pollen vigorously germinated in stigma, and pollen tube was growing. But, 5 days after pollination, pollen tube stopping their growth in the same style as was observed in the cross of self pollination and interspecific pollination. Intrastylar pollination of $L.{\;}{\times}{\;}elegans$ and L. longiflorum passed stylar cannal through the basal part of styles. But, pollen tube that was growing to the ovule of the ovary was extremely small. In morphogical observation of ovary 10 days after pollination, it was observed, that every reciprocal crosses of L. longiflorum ${\times}$ L. ${\times}$ elegans was fertilized through intrastylar pollination, so that this technique was used to overcome cross incompatibilities.lities.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.355-359
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• 2006

This study was carried out to investigate the factors affecting seed germination of Korean native orchids, such as Habenaria radiata, Bletilla striate and Cypripedium macranthum. In general, seeds of H. radiata was effectively germinated on solid medium and the highest germination (29.6%) was achieved on Hyponex solid medium. But shoot growth was better in MS liquid medium containing $100mL\;L^{-1}$ coconut water (MSC medium). Seed germination of B. striata was effectively induced on MS solid medium. However, no seed germination was observed in all liguid medium tested. Seed germination experiments of C. macranthum were performed using 6 kinds of media and seeds harvested 90 days after cross- and self-pollination. Cross-pollinated seeds were germinated on all the media with the best germination ratio of 4.45% on MSC medium. But no germination was observed from self-pollinated seeds.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.116-125
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• 2017

Alpine plants with a scarcity of pollinators in harsh environments have been believed to undergo selfing for reproductive assurance; however, contradictory evidence is also available. Snowmelt regimes in alpine areas function to change life history characteristics of alpine plants such as flowering time and duration; yet the effects of snowmelt regimes have never been tested in alpine plants in Korea. This study was conducted to investigate the dichogamy, mating systems, and flowering characteristics of Megaleranthis saniculifolia populations [early and late snowmelt plots (ESP and LSP, respectively)] in a subalpine area of Sobaeksan Mountain in Korea. M. saniculifolia exhibited incomplete protogyny in that despite early maturation of pistils, maturation times of pistils and stamens within flowers were partly overlapped. Control and hand-outcrossing treatments produced significantly higher number of follicles and seeds per flower than autonomous and hand-selfing treatments. Based on the aggregate fruit set, the auto-fertility index (AI) and self-compatibility index (SI) were 0.33 and 0.50, respectively. Snowmelt occurred 10 days earlier in ESP than in LSP, thereby ESP and LSP showed distinct differences with regard to flower longevity and season, but showing no difference in peak flowering dates. We concluded that M. saniculifolia is an incomplete protogynous and largely outcrossing plant requiring pollinator service. Temporal variation in snowmelt time and subsequent changes in flowering characteristics under climate change may further threaten the population persistence of M. saniculifolia which has already been designated as endangered species in Korea.

• Proceedings of the KIEE Conference
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• 2004.05b
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• pp.66-72
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• 2004

본 연구는 접지저감제의 성분으로 수용성 고분자의 유기물과 층상형 점토의 무기재료를 주재료하여 새롭게 개발한 새로운 형태의 접지저감제의 성능비교에 관한 것이다. 신개발의 접지저감제는 수분을 흡습하여 수분에 용해된 수용성고분자가 수분과 함께 층상형점토의 층으로 삽입되어 접지저감 성능을 발휘하게 된다. 본 연구의 유 무기 복합재료형 접지저감제는 함수율과 팽창률이 매우 우수할 뿐 아니라 300wt%의 수분을 공급 후 측정한 전기전도도도 매우 뛰어나다. 또한 환경친화적인 천연재료들이므로 인체나 환경에 매우 안전하며, 접지전극의 부식과 전식을 방지하는 기능이 매우 뛰어나 염해나 화학적으로 부식성이 높은 토양에서 큰 장점을 갖는다. 본 논문에서는 신개발의 접지저감제와 기존의 여러 접지저감의 성능을 비교 분석하였다. 이를 위해 현장의 대지저항율을 측정 분석하여 각각의 접지저감제의 접지설계에 적용하여 시뮬레이션하였으며, 시뮬레이션 결과와 현장에서 실제 시공한 측정 결과와 비교 분석하였다.