• Title/Summary/Keyword: 엽형

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타원계 비원형기어(엽형)의 설계에 관한 연구

  • 고윤호;최상훈
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1993.10a
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    • pp.622-626
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    • 1993
  • 비원형기어의 기본적인 특징을 몇 가지 소개하고자 한다. 첫째, 간소한 기구로서 소형화할 수 있고, 둘째, 임의의 부동속 회전 전달을 얻을 수 있으며, 셋째, 맞물린 치면의 미끄럼접촉이 적기 때문에 마모피로가 적고 넷째, 고부하 전달이 가능하다는 장점들이 있다. 본 연구의 목적은 링크, 캠과 같은 동일한 용도에서 사용되는 다른 여러 기구에 비해 많은 이점을 가지고 있는 적합한 타원계 비원형기어(엽형)에서 편평도의 변화에 따른 피치라인을설계하고, 각속비 및 편평도에 따른 형상과 길이의 변화, 물림압력각, 곡률반경등의 연구를 바탕으로 스퍼형과 헬리컬형의 타원계 엽형로타를 AOTOCAD의 script, 3dace를 이용하여 Computer Simulation를 통해 도형화한다.

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Leaf Area of Korean Local Soybean Collection (재래종 수집대두계통의 엽면적)

  • Shin-Han Kwon;Kun-Hyuk Im;Jae-Ri Kim
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.19
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    • pp.47-51
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    • 1975
  • Leaf area and its relationships with other important agronomic traits were investigated with 727 lines of Korean local soybeans. Distributions of the leaf area, length, leaf width and LAI of the lines were shown in normal curves. Leaf area was positively associated with leaf length, and width, plant height, and seed size. Leaf form is rather affected by leaf width than leaf length.

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Classification of Needle Type and Growth Characteristics of Cryptomeria japonica Planted in Cheju Province (삼나무의 엽형분류(葉型分類) 및 생장특성(生長特性)에 관(關)한 연구(硏究) -제주도(濟州道)를 중심(中心)으로-)

  • Jin, Hyun O;Chon, Sang-Keun
    • Journal of Korean Society of Forest Science
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    • v.76 no.4
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    • pp.410-417
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    • 1987
  • Needle type and growth characteristics of Cryptomeria japonica planted in Cheju, Korea, were investigated and compared with those of the same species distributed in Japan. Needle types were classified into nine lines, and the stands were composed of more than six lines. The trees of the same needle type as Ura-Sugi (Cryptomeria japonica) in Japan showed the best growth in height.

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Growth characteristic of lettuce (Lactuca sativa L.) based on Pulse Width modulation of artificial light sources with UV-A. (UV광원을 포함한 인공광원의 펄스폭 변조에 따른 적치마 상추의 생육특성)

  • Kwak, Su-Ji;Kwak, Eun-Ji;Lee, Hyun-Hee;Lee, Seung-Ki;Han, Jae-Woong;Jeon, Myung-Jin;Kim, Woong
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2017.04a
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    • pp.123-123
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    • 2017
  • 식물공장 내 작물의 생육은 제공되는 인공광원의 광원 및 광질에 영향을 받으며, 광흡수 파장에 따라 다르다. 또한 광합성에 효과적인 형태의 빛의 계속적인 빛의 조사보다는 광 펄스를 조절하여 공급하여 준다면 더욱더 효과적인 생육 환경을 제공해 줄 수 있다. 식물의 최적 생장을 위해 특정 파장대의 빛을 선택적으로 조사할 수 있는 LED특성을 사용하여 UV광원을 포함한 인공광원의 펄스폭 변조에 따른 적치마 상추의 생육특성을 알아보고자 하였다. 광환경은 Red(660 nm), Blue(450 nm), UV(395 nm) LED를 8:1:1 비율로 광량 $160{\mu}mol{\cdot}m^2{\cdot}s^{-1}$, 주파수 1.25, 2.5, 3.75, 5.0 kHz로 조사하여 주었으며, 온도 $20{\sim}23^{\circ}C$, 습도 50~60%, $CO_2$농도 1,000 ppm으로 조성하여 주었다. 아시아종묘 적치마상추를 파종 후 18일 째 되는날 정식, 정식 후 14일 28일 째 되는날 SPAD, 지상부 지하부의 생체중 및 건물중, 엽폭, 엽장을 측정하였으며, 측정한 엽폭과 엽장을 이용하여 엽형지수 산출, 지상부 지하부 생체중 값을 이용하여 S/R율을 산출하였다. SPAD 측정결과 생육시기가 증가할수록 SPAD함량은 감소하였으며, 1.25와 2.5 kHz에서 생육 시기 증가에 대한 SPAD함량 감소가 컸고, 3.75와 5.0 kHz의 경우 SPAD함량의 감소량은 작았다. 지상부 생체중은 3.75 kHz에서 121.51 g으로 가장 높은 값을 나타냈으며, 2.5, 1.75, 5.0 kHz 순으로 높은 값을 나타났다. 지하부 생체중의 경우 3.75 kHz에서 31.31 g으로 가장 높은 값을 나타냈으며 2.5, 5.0, 1.25 kHz 순으로 높게 나타났다. 엽형지수는 생육 시기가 증가에 따라 감소하는 것으로 나타났으며, 1.75, 2.5, 5.0, 3.75 kHz 순으로 크게 나타났다. 지상부 건물중 측정결과는 지상부 생체중 결과와, 지하부 건물중의 측정결과는 지하부 생체중 결과와 동일하였다. S/R율은 1.75 kHz를 제외하고 생육시기가 증가할수록 S/R율은 감소하는 것으로 나타났으며, 주파수가 높아질수록 S/R율은 감소하는 것으로 나타났다. 엽형지수는 엽폭/엽장으로 엽형지수를 산출한 결과로 값이 작을수록 엽폭이 넓은 형태를 의미하며, 생체중값이 가장 크게 나타났던 3.75 kHz에서 엽형지수의 값이 가장 낮게 나타났으며 3.75 kHz를 제외하고 주파수가 높을수록 엽형지수의 값이 낮게 나타났다. 이에 주파수에 따른 적상추의 생육은 3.75 kHz에서 가장 좋은 것으로 판단할 수 있었다.

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Variation of Leaflet Traits and Their Association with Agronomic Traits of Soybean Germplasm (콩 유전자원의 소엽형질 변이와 농업형질과의 관계)

  • Yeong Ho, Lee;Yung Kuang, Huang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.42 no.5
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    • pp.640-646
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    • 1997
  • To determine variations in leaflet length (LL), leaflet width (LW), leaflet size (LS), and leaflet shape index (LSI), and their association with eight agronomic traits, characterization data of 884 soybean accessions which were grown in the autumn of 1992 in Taiwan were analyzed. LL ranged from 4.3 to 14.7 cm, and LW ranged from 2.8 to 9.7 cm. Also, LS (LL $\times$ LW) ranged from 12.1 to 124.6 $\textrm{cm}^2$. The absolute variation of LL, LW, and LS was not large because of limitation in vegetative growth by short day length. None was classified as a large leaflet based on the International Board for Plant Genetic Resources (IBPGR) descriptors. LSI (LL /LW) ranged from 1.21 to 3.06, and three accessions were classified as narrow leaflet. There were differences in ranges and means of LL, LW, LS, and LSI between and within temperate and tropical accessions. LL, LW, LS, and LSI had highly significant positive correlations with seven agronomic traits and highly significant negative correlation with 100-seed weight except LW for all accessions. There was variation in the closeness of association among leaflet traits, and between and within temperate and tropical accessions. Generally, LL, LW, and LS were more closely associated with days to flowering, plant height at $R_1$ and $R_8$, number of pods per plant; LSI was more closely associated with 100-seed weight than other traits.

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Species Diversity and Leaf Form of Ginkgoaleans from the Mesozoic and Cenozoic Strata in Korea (우리나라의 중생대와 신생대 지층에서 산출된 은행류의 종의 다양성과 엽형)

  • Kim, Jong-Heon
    • Journal of the Korean earth science society
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    • v.30 no.1
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    • pp.1-9
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    • 2009
  • This paper conducted the general review of the 6 genera and 22 species of ginkgoaleans known from the Mesozoic and Cenozoic strata of Korea based on the recent palaeontological knowledge. Species diversity and leaf form of the Mesozoic and Cenozoic ginkgoaleans were discussed. Results showed that 4 genera 8 species from the Mesozoic strata and 1 genus and 1 species from the Cenozoic strata were recognized respectively. Laminae of the Mesozoic type of ginkgoaleans were mostly split into narrow lobes, but those of the Cenozoic type were characterized by their fan-shaped simple leaf.

Studies on the Breeding of the Response to short photoperiod, Fiber weight, and Qualitative characters and of the Associations Among these characters in Kenaf (섬유용양마의 육종에 관한 연구 -단일반응성과 섬유종의 유전 및 연소)

  • Johng-Moon Park
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.4 no.1
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    • pp.115-124
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    • 1968
  • It was shown that the most desirable characters for kenaf are high-fiber weight and moderately early maturity. Therefore, the objectives of this research on this crop is to find varieties possessing these characteristics. The experiments covered in this report provided new information relative to segregation, mode of inheritance, estimate of the number of genes involved in fiber weight and their response to short day length of 10 hours and the qualitative characters, such as, color of stem, capsule, petiole and shape of leaves. The associations which exist among these characters are also indicated. Fiber weight per plant, days to flowering, Stem color, Petiole color, Capsule color, and shape of leaves were studied in parental, $F_1$.$F_2$and backcross populations of a cross between Dashkent, a low-fiber weight but early maturing kenaf variety, and G 38 F-1, a high-fiber weight but late maturing kenaf variety. Crosses were made using the varieties, Dashkent and G 38 F-1 as parents. The Dashkent parent had the following characteristics: green stems, capsules and petioles and lobed shaped leaves; 105.8234 mean-days to flowering in the field, and 106.9222 mean-days under 10 hours short day treatment. The other parent, G 38 F-1 had red stems yellow capsules and red petioles and unlobed shaped leaves; 149.8921 mean-days to flowering in the field, and 62.3684 mean-days under 10 hours short day treatment. Both of the parents, $F_1$, $F_2$, $BC_1$ ($F_1$ X Dashkent, ) and $BC_2$($F_1$ ${\times}$ G38F-1) of the kenaf cross were grown at the Crops Experiment Station, Suwon, Korea in 1965. Color of stems, petioles and capsules, and shape of leaves were noted to be simply inherited as a single factor. Red stem color was dominant over green stem color, red petiole color was dominant over green petiole, lobed shaped leaves were dominant over unlobed shaped leaves and yellow capsules were dominant over green capsule. It was, also, noted that the factor for color of petiole was linked with the factor for shape of leaf with a 11.9587 percent recombination value, however no interaction or linkage were found among the color of stem and capsule color. Using Powers partitioning method, theoretical means and frequency distributions for each population, the days to flowering were calculated with the assumption that two gene pairs were involved. The values obtained fitted the theoretical values. In general this would indicate that Dashkent and G 38 F -1 were differentiated by two gene pairs. Heritability values were calculated as the percent of additive genetic variance. Heritability value of days to flowering, 89.5% in the broad sense and 79.91% in the narrow sense, indicated that the selection for this character would be effective in relatively early generations. Particularly, high positive correlations were found between days to flowering and the color of petioles and shape of leaves. However, there was no relation between days to flowering and capsule color nor between these and stem color. On the basis of the results of this experiment there is evidence that the hereditary factor for shape of leaves and the color of petioles is linked with an effective factor or factors for the characters of days to flowering. The association was sufficiently close to offer a possible simple and efficient means of selection for moderately early mat. uring plants by leaf shape and petiole color selection. Again using Powers partitioning method the frequency distribution for each population to the fiber weight were calculated with the assumption that two gene pairs, AaBb, were involved. Both phenotypic and genotypic dominance were complete. The obtained value did not agree with the theoretical value for $F_2$ and $BC_1$ ($F_1$ ${\times}$ Dashkent.) It seems that Dashkent and G 38 F-1 were differentiated by two major gene pairs but some the other minor genes are necessary. It is certain that the hereditary factor for shape of leaves and color of petioles is linked with an effective factor or factors for fiber weight. Also, high. yielding plants with moderately early maturity were found in the $F_2$ population. Thus, simultaneous selection for high-fiber yield and moderately early maturing plants should be possible in these populations. Phenotypic and genotypic correlation coefficients between fiber weight per plant and days to flowering, stem height and stem diameter were calculated. In general, genotypic correlations are higher than the phenotypic correlation. The highest correlation is found between stem height and fiber weight per plant (0.7852 in genotypic and 0.4103 in phenotypic) and between days to flowering and fiber weight per plant (0.7398 in genotypic and 0.3983 in phenotypic.) It was also expected that the selection of high stem height and moderately early maturing plants were given the efficient means of selection for high fiber weight.

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Design of Elliptical Lobe Type Gear with Involute Profile (타원계 엽형기어의 설계 및 동특성에 관한 연구)

  • 유명섭
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.4
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    • pp.7-14
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    • 1998
  • Noncircular gears have been used for obtaining the modified anglualr velocity ratio between parallel axes. The elliptical gear, which is a kind of noncircular gears, makes use of ellipse as a pitch curve, and is applied for the measurement of the discharge of liquid. The applications of an elliptical gear are more advantageous than any other mechanism as like a crank-slider linkage or a cam mechanism in view of the accuracy and the reliability to transmit the prescribed motion. In this paper, acceding to the theoretical involute tooth profile, two pairs of the elliptical gears were manufactured by using CNC wire electronic discharge machine. The proper ranges of the operating pressure angle and of module not to generate under cutting are studied on the change of the eccentricity, because it is the eccentricity of the pitch curve that determines most of the characteristics of the elliptical gear and then the vibration analysis is executed for the verification of harmonious rotating.

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Leaf Type Characteristics of Prunus mume (201 Trees) in Korea (매실나무 201점의 엽형 특성)

  • Hee Kyoung Kang;Jin Hyuk Kim;Ja Yeon Yi;Eun Su Ju;Min Kyung Choi;In Cheol Baek;Tae Hyun Ha;Hong Seon Song
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.08a
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    • pp.29-29
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    • 2020
  • 본 연구는 현재 공주대학교 포장에 보존되어 있는 식용, 약용, 관상용 등의 매실나무 유전자원에 대한 외부 형태적 특성평가를 통하여 향후 우수한 종자원 확보와 양묘생산의 토대 및 육종을 위한 소재로 활용할 수 있는 기초 정보를 제공하기 위하여 실시하였다. 매실나무의 엽형은 난형에 가까웠는데, 엽장은 평균 76.9±9.7mm (최소 52.0mm, 최대 102.0mm)이었으며, 엽폭은 평균 41.9±6.4mm (최소 27.0mm, 최대 60.0mm)이었고, 엽병장은 평균 9.5±2.6mm (최소 4.0mm, 최대 24.0mm)이었다. 이들 형질의 변이계수는 엽병장이 27.7%로서 가장 높아 엽장과 엽폭에 비해 진폭이 컸으며, 다음으로 엽폭 (15.3%), 엽장 (12.6%) 순이었다. 매실나무 엽장은 71~80mm에서 가장 높은 비율 (50.3%)을 나타내었으며, 다음으로 81~90mm (21.9%), 61~70mm (12.4%), 91mm 이상 (8.0%), 60mm 이하 (7.4%) 순이었다. 엽폭은 41~50mm에서 가장 높은 비율 (45.8%)을 나타내었으며, 다음으로 31~40mm (41.8%), 51mm 이상 (7.4%), 30mm 이하 (5.0%) 순이었다. 엽병장은 6~10mm에서 가장 높은 비율 (72.6%)을 나타내었으며, 다음으로 11~15mm (22.4%), 16mm 이상 (3.0%), 5mm 이하 (2.0%) 순이었다. 엽형 형질 간의 상관계수는 모두가 0.2 이하로 상관관계가 약하였으나 표본수가 많아 유의한 값을 나타내었으며, 엽장과 엽폭이 0.242로 가장 높았고, 다음으로 엽장과 엽병장 (0.173), 엽폭과 엽병장 (0.001) 순이었다.

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