• Title/Summary/Keyword: Root characteristics

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Studies on the Relationship between Standing Crop of Miscanthus sinensis Grassland and Soil Morphological Characteristics (억새초지의 현존량과 토양의 형태적 특성에 관한 연구)

  • 박봉규
    • Journal of Plant Biology
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    • v.21 no.1_4
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    • pp.7-12
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    • 1978
  • The results of the relationship between standing crop of Miscanthus sinensis grassland and soil morphological characteristics are as follows. The Miscanthus sinensis grassland seems to grow well in volcainc ash soil. The depth of A layer was closely related to the standing crop of the Miscanthus sinensis grassland. The root systems of Miscanthus sinensis reached to its maximum in A layer. The root systems of Miscanthus sinensis showed its maximum at 20mm and below(soil hardness). The soil texture of A layer showed SL-SiL. The soil structure of A layer contained Massive-Small Granular. The soil colors of A layer expressed Dark Yellowish Orange-Brownish Black.

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Selection of Angelica gigas Nakai Lines Using Seedling Characteristics (유묘특성(幼苗特性)을 이용한 참당귀(當歸) 계통(系統)의 조기선발(早期選拔))

  • Yu, Hong-Seob;Bang, Jin-Ki;Kim, Young-Guk;Lee, Seung-Tack
    • Korean Journal of Medicinal Crop Science
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    • v.5 no.3
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    • pp.191-195
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    • 1997
  • This study was conducted to obtain the basic information on setting up selection procedure using seedling characteristics in Angelica gigas Nakai lines. Morphological characteristics of the seedlings including height, leaf and petiole length among lines tested showed difference significantly, meaning that earlier selection was possible. Bolting rate at maturity ranged from 0.6 to 74.6% and root yield did from 350 to 3,893kg/ha. Root yield was increased in the lines with below 5% bolting rate. Heritabilities of petiole length, seedling height and leaf length in seedling stage bolting rate and root yield were high, while those of leaf length, root diameter and root length were relatively low. Bolting rate at maturity was positively correlated with seedling height, leaf length, leaf width, petiole length and number of leaves. A highly significant negative correlation was showed between root yield and seedling height, leaf length and width, petiole length, number of leaves, root length or bolting rate. From the above results the selection markers were found to be height, leaf length and petiole length in seedling stage.

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Simple Design of Equiripple Square Root Pulse Shaping Filter (Square-root 형 등리플 파형성형 필터의 간단한 설계)

  • 황정진;오우진
    • Proceedings of the IEEK Conference
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    • 2001.06d
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    • pp.261-264
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    • 2001
  • In this paper, we introduce a simple design method f9r mot-squared type raised cosine filter with equiripple characteristics. Through some design examples, we show that the proposed filter has much better performance in ripple than the conventional SRCF at the expense of small increasing of ISI. In addition, the proposed Inter is compatible with conventional SRCF. Finally, we designs the filter for W-CDMPI which uses RRC (Root Raised Cosine) with a=0.22, in 12bit finite precision.

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Black Dot Root Rot of Tomato Caused by Colletotrichum coccodes (Colletotrichuym coccodes에 의한 토마토 검은점뿌리썩음병(흑점근부병))

  • 김완규;지형진;조원대
    • Korean Journal Plant Pathology
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    • v.14 no.3
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    • pp.209-211
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    • 1998
  • Black dot root rot occurred severely in greenhouse tomatoes in jangseong area of Korea in April, 1996. The causal fungus of the disease was identified as Colletotrichum coccodes based on the morphological and cultural characteristics. Pathogenicity tests revealed that isolates of the fungus were responsible for the disease, and two cultivars of cherry tomato were less susceptible to the disease than other cultivars of tomato and cherry tomato tested.

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Study of Welding Toughness Characteristics on the Root-pass Welding Process of High Tensile Steel at Tower Production for Offshore Wind Power Generation (해상풍력 발전용 타워 제작시 고장력강재의 초층용접에 관한 용접특성 연구)

  • Jung, Sung-Myoung;Kim, Ill-Soo;Kim, Ji-Sun;Na, Hyun-Ho;Lee, Ji-Hye
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.2
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    • pp.349-353
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    • 2012
  • As the world wind energy market grows rapidly, the productions of wind power generation equipment have recently increased, but manufacturers are not able meet this requirement. Particularly offshore wind energy industry is one of the most popular renewable energy sectors. To generalize welding processes, the welding automation is considered for steel structure manufacturing in offshore wind energy to get high quality and productivity. Welding technology in construction of the wind towers is depended on progress productivity. In addition, the life of wind tower structures should be considered by taking account of the natural weathering and the load it endures. The root passes are typically deposited using Gas Tungsten Arc Welding(GTAW) with a specialized backing gas shield. Not only the validation consists of welders experienced in determining the welding productivity of the baseline welding procedure, but also the standard testing required by the ASME section IX and API1104 codes, toughness testing was performed on the completed field welds. This paper presents the welding characteristics of the root-pass welding of high tensile steel in manufacturing of offshore wind tower. Based on the result from welding experiments, optimal welding conditions were selected after analyzing correlation between welding parameters(peak current, background current and wire feed rate) and back-bead geometry such as back-bead width(mm) and back-bead height performing root-pass welding experiment under various conditions. Furthermore, a response surface approach has been applied to provide an algorithm to predict an optimal welding quality.

Comparison of Plant Growth and Morphological Characteristics Among the Korean Ginseng, the American Ginseng and the Bamboo Ginseng (고려인삼, 미국삼 및 죽절삼의 생육 및 형태적 특성 비교)

  • 정열영;이명구
    • Journal of Ginseng Research
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    • v.22 no.2
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    • pp.147-153
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    • 1998
  • An investigation was conducted to ascertain the basic information on characteristics of growth and morphological characters among the Korean (Panax. ginseng), the American (Panax. quinquefolium) and the Bamboo (Panax. japonicus) ginseng. In aerial parts growth of the ginseng species by age, The Korean ginseng and American ginseng's stem and leaf growth was alike in 2-4 years old, but growth cycle changed in 6 years old. The Korean ginseng was more vigorous than the American ginseng. The Korean ginseng roots were highly observed in ratio of red skin roots among three species, whereas The American ginseng roots were highly infected by root rot. It seems to be variable depending on growing stage and species. The Korean ginseng flowered about the middle of May, the American ginseng early June, and the Bamboo ginseng was late of May, The berry color of the ginseng species was observed, The Korean and American ginseng's mature berry color was red, The Bamboo ginseng's berry was three type of color and shape. In root characteristics of the seedling, Korean (p. ginseng), American (p. quinquefolium) ginseng's root shape was similarity in type, the bamboo ginseng showed different type, which root length and root weight was smaller than those of ginseng. In morphological characters of Leaf surface, pollen, and stoma, the Korean ginseng and American ginseng had crystal rosette on epidermis cell, but the Bamboo ginseng didn't has crystal rosette. Pollen shape observed tricolpate pollen and size was media type among the ginseng species, and also guard cell was anomocytic type, which were observed by scanning electronic microscope.

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Growth Characteristics of Acanthopanax sessiliflorus Seem Seedling Grown under Different Conditions and Seasons (오갈피나무의 육묘이식재배(育苗移植栽培)에 따른 생육특성(生育特性))

  • Cho, Seon-Haeng
    • Korean Journal of Medicinal Crop Science
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    • v.7 no.1
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    • pp.22-26
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    • 1999
  • This study was investigated to elucidate the growth characteristics of Acanthopanax sessiliflorus grown under different conditions and seasons. The emergence percent of seeds sown in the vinyl house was about 2.2 times better than that in the open field. The plants which had 2 to 3 normal leaves showed the highest value in root setting percent, and the root setting percent was decreased significantly in plants with one normal leaf and 4 to 5 normal leaves. The root setting percent of plants transplanted from April 19 to May 2 was 100%, but plants transplanted at April 4 or from May 17 to June 1 showed lower root setting. Tree percent, plant height. root length and fresh weight of plants grown by transplanting culture were better than those of plants grown by direct seeding.

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Vibration Analysis of Rotating Cantilever Beams with an Elastically Restrained Root (탄성지지단을 갖는 회전하는 외팔 보의 진동해석)

  • Yun, Kyung-Jae;Yoo, Hong-Hee
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.689-694
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    • 2000
  • This paper presents a modeling method for the vibration analysis of cantilever beams with an elastically restrained root. Mass and stiffness matrices are derived explicitly by considering the elastically restrained root coupling effect between stretching and bending motion. Numerical results show that the two effects influence the vibration characteristics of rotating beams significantly. The results also present the magnitude of the elastic stiffness of the root to avoid the dynamic buckling. The method presented in this paper can be used to provide accurate predictions of the variations of natural frequencies of rotating beams with an elastically restrained root.

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Simple Design of Equiripple Square Root Pulse Shaping Filter (자승근형 등리플 파형성형 필터의 간단한 설계)

  • 오우진
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.40 no.2
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    • pp.64-69
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    • 2003
  • In this paper, I introduce a simple design method using existing filter design method, such as Parks-McClecllan algorithm, for root-squared type raised cosine filter with equiripple characteristics, Thought some design examples, we show that the proposed filter has much better performance in ripple than the conventional SRCF at the expense of small increasing of ISI. In addition, the proposed filter is compatible with conventional SRCF. Finally, the filter for W-CDMA which uses RRC (Root Raised Cosine) with a=0.22 is designed in 12bit finite precision.

Development of An Onion Peeler (I) - Root cutting equiment - (양파 박피기 개발(I))

  • 민영봉;김성태;정태상;최선웅;김정호
    • Journal of Biosystems Engineering
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    • v.27 no.4
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    • pp.301-310
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    • 2002
  • With a purpose to manufacture an onion peeler, the root cutting equipment of the onion could be attached to a prototype onion peeler was developed. Before the experiment, the distribution of the dimensions of the Korean native onion were measured. And some types of the blades to cut and remove the root of the onion were designed and such characteristics as feasible revolution, conveying speed, and power requirement were investigated. From the result of the test, the selected one among the various cutters was the wing type blade with the round blade to cut out the root and with the vertical blade to cut a circular line. The optimum operating conditions of the wing type blade were revealed the revolution with no load was at 630 rpm, and the conveying speed was 0.08 m/s. Under these conditions, the maximum torque was 5.25 kg·m and the power requirement was 33 W, respectively.