• 제목/요약/키워드: root development

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초음파탐상 검사를 이용한 증기터빈 블레이드 루트 휭거 균열 탐지기법 개발 (Development of Crack Detecting Method at Steam Turbine Blade Root Finger using Ultrasonic Test)

  • 윤완노;김준성;강명수;김덕남
    • 한국정밀공학회지
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    • 제28권6호
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    • pp.738-744
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    • 2011
  • The reliability of blade root fixing section is required to endure the centrifugal force and vibration stress for the last stage blade of steam turbine in thermal power plant. Most of the domestic steam turbine last stage blades have finger type roots. The finger type blade is very complex, so the inspection had been performed only on the exposed fixing pin cross-section area due to the difficulty of inspection. But the centrifugal force and vibration stress are also applied at the blade root finger and the crack generates, so the inspection method for finger section is necessary. For the inspection of root finger, inspection points were decided by simulating ultra-sonic path with 3D modeling, curve-shape probe and fixing jig were invented, and the characteristics analysis method of ultrasonic reflection signal and defect signal disposition method were invented. This invented method was actually executed at site and prevented the blade liberation failure by detecting the cracks at the fingers. Also, the same type blades of the other turbines were inspected periodically and the reliability of the turbine increased.

Plant regeneration from the root-derived embryonic tissues of Rosa hybrida L. cv. Charming via a combined pathway of somatic embryogenesis and organogenesis

  • Kim, Suk Weon;Oh, Myung Jin;Liu, Jang R.
    • Plant Biotechnology Reports
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    • 제3권4호
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    • pp.341-345
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    • 2009
  • This study describes culture conditions for a plant regeneration system via a combined pathway of somatic embryogenesis and organogenesis in root explant cultures of the commercial rose cultivar 'Charming'. Root explants formed white calluses at a frequency of 30% after 6 weeks of culture on Schenk and Hildebrandt (SH) medium supplemented with $11mg\;1^{-1}$ 2,4-dichlorophenoxyacetic acid. After 6 weeks of transfer to SH medium without growth regulators, initial white calluses gave rise to globular somatic embryos at a frequency of 2.8%, which were subsequently dedifferentiated to embryonic tissues. Somatic embryos or embryonic tissues initially derived from root explants did not undergo development beyond cotyledonary stage. To produce adventitious shoots, embryonic tissues were sliced and cultured on SH medium with $0.5mg\;1^{-1}$ 6-benzyladenine. After 4 weeks of culture, 28% of embryonic tissue explants formed adventitious shoots. Regenerated shoots were rooted on half strength SH medium with $0.1mg\;1^{-1}$ ${\alpha}-naphthalaneacetic$ acid and subsequently grown to maturity. Root-derived embryonic tissues were proliferated by subculture, while retaining the capacity for shoot production for a few years.

편백 1, 2년생 노지묘와 용기묘의 생장특성 비교 (Comparison of Growth Characteristics of 1- and 2-year-old Bare Root and Container Seedling of Chamaecyparis obtusa)

  • 송기선;차영근;최진영;김종진
    • 한국산림과학회지
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    • 제101권2호
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    • pp.317-323
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    • 2012
  • 본 연구는 우리나라 남부지방의 주요 조림수종인 편백(Chamaecyparis obtusa Sieb. et Zucc.) 노지묘와 용기묘의 생육단계별 생장특성을 탐구하고자 수행되었다. 1년생 노지묘의 간장생장은 용적이 31.2 mL와 300 mL 용기에서 생장한 용기묘 보다 좋았으며, 근원경 생장은 300 mL 용기의 용기묘가 가장 좋았다. 2년생 노지묘는 300 mL 용기의 용기묘보다 간장 및 근원경생장이 양호한 것으로 조사되었다. 건물생산량 비교에서, 1년생 지상부는 32 mL 용기묘가, 지하부 및 전체 건물생산량은 300 mL 용기묘가 가장 높았다. 2년생의 경우는 지상부는 노지묘가, 지하부는 용기묘의 건물생산량이 높은 것으로 나타났다. 뿌리전체길이, 뿌리투영단면적, 뿌리표면적, 뿌리평균직경, 뿌리부피 등 묘목의 뿌리형태 특성 비교에서, 1, 2년생 용기묘 모두 뿌리평균직경을 제외하고는 노지묘보다 더 높은 생장을 보였다. 본 실험의 결과를 종합해 볼 때, 편백 묘목생산과정에서 용기묘가 노지묘에 비해 상대적으로 뿌리발달이 뛰어난 묘목으로 생장한 것으로 판단된다.

독활(獨活)(Aralia continentalis K.) 주산지(主産地) 토양특성(土壤特性)과 시비양분(施肥養分)이 근경수량(根莖收量)에 미치는 영향 -II. 3요소(要素) 시비수준별(施肥水準別) 수량반응(收量反應)과 무기성분(無機成分) 흡수(吸收) (Effect of Soil Characteristics and Fertilizer Application on Fresh Root Yield of Aralia continentalis K. -II. Yield Response to N, P, K Application rates and Nutrient Uptake)

  • 오동훈;황남열;나종성;박건호
    • 한국토양비료학회지
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    • 제27권3호
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    • pp.209-214
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    • 1994
  • 독활(獨活)에 대(對)한 3요소(要素) 시비량(施肥量) 차이(差異)가 생육(生育) 및 수량반응(收量反應)과 양분흡수(養分吸收)에 미치는 영향(影響)을 구명(究明)하고 적정(適正) 시비량(施肥量)을 얻고자 축행(逐行)과 시험결과(試驗結果)는 다음과 같다. 1. 시비량(施肥量) 증가(增加)에 따라 파종후(播種後) 1년차(年次)와 2년차(年次) 공(共)히 지상부(地上部) 생육(生育)과 뿌리수량(收量)이 증가(增加)되었고 회귀식(回歸式)에 의한 2년차(年次) 3요소(要素) 적정시비량(適正施肥量)턴은 10a당(當) 질소(窒素) 38kg, 인산(燐酸) 21kg, 가리(加里) 18kg이었다. 2. 독활(獨活)의 뿌리수량(收量)에 대(對)한 제형질(諸形質)의 기여도(寄與度) 값을 비교(比較)해 본 결과(結果) 초장(草長), 근경(根徑), 묘두수(苗頭數), 경대(莖大), 근수(根數) 순(順)으로 나타났다. 3. 3요소별(要素別) 상대수량(相對收量) 지수(指數)는 질소(窒素), 가리(加里), 인산(燐酸) 순(順)으로 낮았고, 시비효율(施肥效率)은 가리(加里), 인산(燐酸), 질소(窒素) 순(順)으로 높았다. 4. 독활(獨活) 잎의 무기성분(無機成分) 분석결과(分析結果) 석회함량(石灰含量)이 가장 많은 반면(反面), 인산함량(燐酸含量)이 적게 함유(含有)되어 있고 질소(窒素)와 가리(加里) 시비량(施肥量)이 증가(增加)함에 따라 잎의 질소(窒素)와 가리함량(加里含量)도 증가(增加) 경향이었으며 특히 질소함량(窒素含量)이 뿌리수량(收量)과 고도(高度)의 유의성(有意性) 있는 정의 상관(相關)을 보였다. 5. 무기질비료(無機質肥料)와 유기질비료(有機質肥料) 처리간(處理間)의 생약(生藥) 일반성분함량(一般成分含量) 즉 이물함량(異物含量), 회분(灰分), 에탄올 추출 엑기스를 비교(比較) 분석(分析)한 결과 두 처리(處理)간에 뚜렷한 성분함량(成分含量) 차이(差異)를 인정(認定)할 수 없었다.

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Growth and yield responses of rice varieties to various soil water deficit conditions under different soil types

  • Kikuta, Mayumi;Samejima, Hiroaki;Magoti, Rahab;Kimani, John M.;Yamauchi, Akira;Makihara, Daigo
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.322-322
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    • 2017
  • To avoid drought stress under rainfed upland conditions, it is important for rice to efficiently utilize water at shallow soil layers supplied by rainfall, and access to water retained in deer soil layers. The root developmental characteristics of rice, which play important role in the adaptability to drought conditions, vary depending on the variety. Moreover, water availability for plant differs depending on the soil types that have different physical properties such as water holding capacity, permeability, capillary force, penetration resistance, etc. In this study, we evaluated growth and yield responses of rice varieties to various soil water deficit conditions under three different soil types. The experiment was conducted in a plastic greenhouse at the Kenya Agricultural and Livestock Research Organization-Mwea from October 2016 to January 2017. Two upland varieties (NERICA 1 and 4) and one lowland variety (Komboka) were grown in handmade PVC pots (15.2 cm diameter and 85.0 cm height) filled with three different types of soil collected from major rice-growing areas of the country, namely black cotton (BC), red clay (RC), and sandy clay (SC). Three watering methods, 1) supplying water only from the soil surface (W1), 2) supplying water only from the bottom of the pots (W2), and 3) supplying water both from the soil surface and the bottom of pots (W3), were imposed from 40 days after sowing to maturity. Soil water content (SWC) at 20, 40, and 60 cm depths was measured regularly. At the harvesting stage, aboveground and root samples were collected to determine total dry weight (TDW), grain yield, and root length at 0-20, 20-40, 40-60, and 60-80 cm soil layers. Irrespective of the watering methods, the greatest root development was obtained in RC, while that in BC was less than other two soils. In BC, the degree of yield reduction under W1 was less than that in RC and SC, which could be attributed to the higher water holding capacity of BC. In RC, the growth and yield reduction observed in all varieties under W1 was attributed to the severe drought stress. On the other hand, under W2, SWC at the shallow soil depth in RC was maintained because of its higher capillary force compared with BC and SC. As the result, growths and yields in RC were not suppressed under W2. In SC, deep root development was not promoted by W2 irrespective of the varieties, which resulted in significant yield losses. Under W1, the rice growth and yield in SC was decreased although shallow root development was enhanced, and the stomatal conductance was maintained higher than RC. It was suspected that W1 caused nutrients leaching in SC because of its higher permeability. Under rainfed conditions, growth and yield of rice can be strongly affected by soil types because dynamics of soil water conditions change according to soil physical properties.

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천궁(川芎)(Cnidium officinale Makino)의 산지별(産地別) 재배종(裁培種)과 종근중(種根重)이 수량(收量) 및 품질(品質)에 미치는 영향(影響) (Effects of the Seed Root Weight and the Local Varieties on the Yield and Quality of Cnidium officinale Makino root)

  • 장상문;최정;정상환;서동환
    • Current Research on Agriculture and Life Sciences
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    • 제6권
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    • pp.87-91
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    • 1988
  • 양질(良質)의 천궁근(川芎根)을 생산(生産)하기 위한 우량품종(優良品種)을 선발하기 위한 목적(目的)으로 각(各) 주산지(主産地)의 재배산(栽培産) 종근(種根)을 수집하여 종근(種根)의 무게를 표준구(標準區)(20~25 g)와 소구(小區)(15~20 g)로 구분(區分)하여 재배(栽培)한 결과(結果)를 다음과 같이 요약(要約)하였다. 주당(株當) 생근(生根) 및 건조근(乾燥根)의 중량(重量)은 표준구(標準區)가 92.7 g 과 18.5 g 이었으며, 소구(小區)에서는 94.5 g 과 17.0 g 이었다. 지역간(地域間)에는 울릉산(鬱陵産)이 타지역산(他地域産)에 비(比)하여 많았다. 생근(生根) 및 건조근(乾燥根)의 수량(收量)은 표준구(標準區)의 경우 906.8kg/10a와 190.2kg/10a이었으며, 소구(小區)에서는 721.2kg/10a, 165.2kg/10a으로서 표준구(標準區)의 수량(收量)이 더 많았으며, 울릉산(鬱陵産)의 수량(收量)이 타지역산(他地域産)에 비(比)하여 많았다. 회분(灰分) 및 에테르엑기스함량(含量)은 각각(各各) 3.38~3.59%와 3.67~3.87%의 범위에 속(屬)하였으며, 대전(大田), 공주산(公州産)은 회분함량(灰分含量)이, 울릉산(鬱陵産)은 에테르엑기스함량(含量)이 비교적 많았다. 표준구(標準區)에서는 주당(株當) 근중량(根重量) 및 수량(收量)은 에테르엑기스함량(含量)과 고도(高度)의 정(正)의 상관(相關)이, 소구(小區)에서는 회분함량(灰分含量)과 정(正)의 상관(相關)이 인정(認定)되었다. 그러므로 천궁(川芎) 재배시(栽培時)에는 종근(種根)의 무게가 20 g 이상(以上)인 울릉산(鬱陵産)을 선정(選定)함이 수량(收量) 및 품질(品質)이 우수(優秀)한 천궁근(川芎根)을 생산(生産)할 수 있을 것으로 판단(判斷)되었다.

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'Kowon', a New Korean Ginseng Cultivars with High Yield and Alternaria Blight Resistance

  • Kim, Young Chang;Kim, Jang Uk;Lee, Jung Woo;Hong, Chi Eun;Bang, Kyong Hwan;Kim, Dong Hwi;Hyun, Dong Yun;Choi, Jin Kook;Seong, Bong Jae;An, Young Nam;Jeong, Haet Nim;Jo, Ick Hyun
    • 원예과학기술지
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    • 제35권4호
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    • pp.499-509
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    • 2017
  • Recently, there has been increased attention to the development of new plant cultivars with enhanced resistance to biotic and abiotic stress. To develop ginseng cultivars with such traits, systematic breeding programs and comprehensive field studies are prerequisites. In this study, we applied a pure-line selection method to identify a ginseng cultivar with enhanced stress resistance. Phenotypic and agronomic characteristics, seed yield, and physiological responses to biotic and abiotic stresses were investigated according to the guidelines of the International Union for the Protection of New Varieties of Plants (UPOV). In the newly developed 'Kowon' cultivar, the time of emergence, flowering, and berry maturity were intermediate between those of the controls, 'Yunpoong' and 'Chunpoong'. The stem length of 'Kowon' was intermediate, whereas the root length was shorter and the main root diameter was greater than those of 'Chunpoong'. In local adaptability tests conducted in three regions, the yield of 'Kowon' was $666kg{\cdot}10a^{-1}$; 27% and 4% higher than that of 'Chunpoong' and 'Yunpoong'. Diseases such as Alternaria blight, Phytophthora blight, mulberry mealybug, and nematode infestation did not occur in 'Kowon'; and it also exhibited moderate resistance to damping-off and anthracnose. In these cases, yellow spots occurred on aerial parts and the rusty skin of the root, and it exhibited moderate resistance at high temperatures. Our study demonstrates that 'Kowon', which has a high root weight and enhanced biotic/abiotic stress resistance, is a superior cultivar that could increase farmers' income.

Cylindrocarpon destructans/Ilyonectria radicicola-species complex: Causative agent of ginseng root-rot disease and rusty symptoms

  • Farh, Mohamed El-Agamy;Kim, Yeon-Ju;Kim, Yu-Jin;Yang, Deok-Chun
    • Journal of Ginseng Research
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    • 제42권1호
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    • pp.9-15
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    • 2018
  • Cylindrocarpon destructans/Ilyonectria radicicola is thought to cause both rusty symptom and root-rot disease of American and Korean ginseng. Root-rot disease poses a more serious threat to ginseng roots than rusty symptoms, which we argue result from the plant defense response to pathogen attack. Therefore, strains causing rotten root are characterized as more aggressive than strains causing rusty symptoms. In this review, we state 1- the molecular evidence indicating that the root-rot causing strains are genetically distinct considering them as a separate species of Ilyonectria, namely I. mors-panacis and 2- the physiological and biochemical differences between the weakly and highly aggressive species as well as those between rusty and rotten ginseng plants. Eventually, we postulated that rusty symptom occurs on ginseng roots due to incompatible interactions with the weakly aggressive species of Ilyonectria, by the established iron-phenolic compound complexes while root-rot is developed by I. morspanacis infection due to the production of high quantities of hydrolytic and oxidative fungal enzymes which destroy the plant defensive barriers, in parallel with the pathogen growth stimulation by utilizing the available iron. Furthermore, we highlight future areas for study that will help elucidate the complete mechanism of root-rot disease development.

Does photobiomodulation on the root surface decrease the occurrence of root resorption in reimplanted teeth? A systematic review of animal studies

  • Theodoro Weissheimer;Karolina Frick Bischoff;Carolina Horn Troian Michel;Bruna Barcelos So;Manoela Domingues Martins;Matheus Albino Souza;Ricardo Abreu da Rosa;Marcus Vinicius Reis So
    • Restorative Dentistry and Endodontics
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    • 제48권3호
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    • pp.24.1-24.16
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    • 2023
  • This review aimed to answer the following question "Does photobiomodulation treatment of the root surface decrease the occurrence of root resorption in reimplanted teeth?" Electronic searches were performed in the MEDLINE/PubMed, Cochrane Library, Scopus, Web of Science, Embase, and Grey Literature Report databases. Risk of bias was evaluated using SYRCLE Risk of Bias tool. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) tool was used to assess the certainty of evidence. In total, 6 studies were included. Five studies reported a reduced occurrence of root resorption in teeth that received photobiomodulation treatment of the root surface prior to replantation. Only 1 study reported contradictory results. The photobiomodulation parameters varied widely among studies. GRADE assessment showed a low certainty of evidence. It can be inferred that photobiomodulation treatment of the root surface prior to replantation of teeth can reduce the occurrence of root resorption. Nonetheless, further clinical studies are needed.

작약(芍藥)의 뿌리굵기와 각피(刻皮)정도가 건조시간 및 품질에 미치는 영향 (Effects of Root Diameter and Peeling Methods on Drying Time and Paeoniflorin Content of Paeonia Lactiflora Pallas)

  • 김기재;박준홍;유오종;신종희;박소득;최부술
    • 한국약용작물학회지
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    • 제6권1호
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    • pp.38-43
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    • 1998
  • 직약 건조시 양질의 약재를 생산하기 위한 기초자료를 얻고자 뿌리굵기에 따라 박피정도를 달리하여 시험한 결과를 요약하면 다음과 같다. 1 작약의 뿌리는 굵기별로 건조하는 것이 건조시간 단축효과가 있었는데, 기계박피시 적정건조 시간은 $5{\sim}10mm$가 20시간, $10{\sim}15mm$가 39시간, $15{\sim}20mm$가 48시간, 20mm 이상이 56시간이었고, 5mm이하는 무박피로 건조하는데 11시간, 노두(蘆頭)는 무박피상태에서 절단 건조할 경우 4시간이 소요되었다. 2. 작약 건조시 가는 뿌리일수록 무박피와 박피간의 건조소요시간의 차이가 적었고, 박피율은 증가하여 수량 손실이 않았으므로 뿌리굵기 10mm 이하는 세척하여 무박피상태로 그 이상은 표피부분만 제거 하고 건조하는 것이 건조시간 단축 및 수량면에서 효율 적인 박피방법이었다. 3. 작약 뿌리 표피부분은 금기에 관계없이 두께가 0.3mm정도인데 무제거 건조가 제거후 건조에 비하여 paeoniflorin함량은 높았으나 건조시간이 장시간 소요되었다. 4. paeoniflorin함량은 뿌리굵기 5mm이하가 6.15%로 가장 높았고, $15{\sim}20mm$까지는 굵기가 굵어 질수록 함량이 감소하였으나, 20mm이상에서는 다시 약간 증가하였고, 표피와 피층부분의 껍질은 많이 제거될수록 함량이 감소하였다.

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