• Title/Summary/Keyword: Root System

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Studies on Root System of the Rice Plants Cultivated in the Reclaimed Land (간척지에 있어서의 수도근군형성에 관한 연구)

  • Won-Il Chung
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.24 no.4
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    • pp.12-18
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    • 1979
  • It has been ascertained by many researchers that soil conditions under which the rice plants were cultivated have some effects upon the root system of the rice plants. But, much is not known about the root systems of the rice plants cultivated in the reclaimed lands. The goal of the present investigation is to study morphogenetical effects of reclaimed land on the development of root system of the rice plant.

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Waterproofing and Root Barrier Construction Design for Artificial Green Roof System of Residential Apartment Underground Parking Lots (공동주택 지하주차장 상부 인공지반녹화층 방수 및 방근 설계 방안)

  • Lee, Jung-Hun;Kim, Bum-Soo;Song, Je-Young;Kim, Soo-Yeon;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.05a
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    • pp.337-338
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    • 2018
  • In recent years, residential apartment building parking lots are built in underground spaces, and with conjunction to improve the environment of the urban area, artificial greeen roof systems are installed on the upper slabs. However, early plant growth are resulting in root penetration into concrete cracks and in turn into the waterproofing membranes, leading to degradation and damaging of the waterproofing system and structural durability. This issue highlights a problem of conventional maintenance system of concrete structures, and proposals for amendments follow. In this study, a waterproofing and root barrier construction design for the upper slabs of residential building underground parking lots is proposed, and motioned to be added into future construction specifications.

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Development of WLAN AP based on IBM 405GP (IBM PowerPC 405GP를 이용한 Wireless LAN Access Point 개발에 관한 연구)

  • Kim Do-Gyu
    • The Journal of Information Technology
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    • v.6 no.3
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    • pp.65-73
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    • 2003
  • The evaluation AP embedded Linux board is implemented. The board is made of IBM 405 GP processor, PPCBoot-1.2.1 boot loader, Linux-2.4.21 kernel and root file system. The evaluation board has two flash memories, boot flash and application flash of size 512Kbyte and 16Mbyte, respectively. And it supports IEEE 802.11a which provide the maximum throughput of 54Mbps in the 5.2GHz frequency band. MTD(Memory Technology Device) and JFFS2(Journalling Flash File System version 2) technologies are adopted to optimally package the system software, boot loader, kernel and root file system. And in order to optimize root file system, busybox package and tiny login are used. Linux kernel and root file system is combined together with mkimage utility.

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Effect of Pot Depth on Root Development and Distribution during Seedling Growing Period in Tobacco. (육묘포트 깊이가 담배의 뿌리발달 및 분포에 미치는 영향)

  • 이상각;심상인;강병화;이학수;석영선
    • Journal of the Korean Society of Tobacco Science
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    • v.19 no.1
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    • pp.18-23
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    • 1997
  • The study was carried out to clarify reasonable production of healthy seedling, optimal Pot depth, and appropriate transplanting time, which can be deduced from understanding of seedling quality. Seedling quality results from growth of root and shoot, morphology and distribution of root system under influence of Pot depth during seedling growing period. Stem height, shoot dry weight, leaf area and leaf number were increased in proportion to depth of pots. Growth of shoot and root during seedling growing period showed the most dramatic development between 20th and 25th day after temporary planting. Root number increased as pot depth decrease and total root length and dry weight increased as pot depth increase. In 5cm pot, relative multiplication rate was higher and mean extension rate was lower than other depth of Pot. The limitation of pot volume in which rhizosphere was located enhance the development of roots of second and third order. At 20th days after temporary Planting root distribution was relatively uniform in length and development of adventitious root on stem base was poor as Pot depth decreased.

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Canal Obturation in Open Apex

  • Oh, Won-Mann
    • Proceedings of the KACD Conference
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    • 2001.11a
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    • pp.572-572
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    • 2001
  • The meaning of obturating root canal is to substitute an inert filling materials in the prepared canal space in order to eliminate all avenues of leakage from the oral cavity or periradicular tissue into root canal system. Inadequate obturation induce the infiltration of periapical tissue fluids, which provide materials for growth of microorganisms or localization of bacteria, into dead space of loosely filled canal. Most parts of endodontic failure is attributed to inadequate obturation of root canal system.(omitted)

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Root metabolic cost analysis for root plasticity expression under mild drought stress

  • Kano-Nakata, Mana;Mitsuya, Shiro;Inukai, Yoshiaki;Yamauchi, Akira
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.328-328
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    • 2017
  • Drought is a major limiting factor that reduces rice production and occurs often especially under recent climate change. Plants have the ability to alter their developmental morphology in response to changing environment, which is known as phenotypic plasticity. In our previous studies, we found that one chromosome segment substitution line (CSSL50 derived from Nipponbare and Kasalath crosses) showed no differences in shoot and root growth as compared with the recurrent genotype, Nipponbare under non-stress condition but showed greater growth responses compared with Nipponbare under mild drought stress condition. We hypothesized that reducing root respiration as metabolic cost, which may be largely a consequence of aerenchyma formation would be one of the key mechanisms for root plasticity expression. This study aimed to evaluate the root respiration and aerenchyma formation under various soil moisture conditions among genotypes with different root plasticity. CSSL50 together with Nipponbare and Kasalath were grown under waterlogged conditions (Control) and mild drought stress conditions (20% of soil moisture content) in a plastic pot ($11cm{\times}14cm$, ${\varphi}{\times}H$) and PVC tube ($3cm{\times}30cm$, ${\varphi}{\times}H$). Root respiration rate was measured with infrared gas analyzer (IRGA, GMP343, Vaisala, Finland) with a closed static chamber system. There was no significant difference between genotypes in control for shoot and root growth as well as root respiration rate. In contrast, all the genotypes increased their root respiration rates in response to mild drought stress. However, CSSL50 showed lower root respiration rate than Nipponbare, which was associated by higher root aerenchyma formation that was estimated based on internal gas space (porosity) under mild drought stress conditions. Furthermore, there were significant negative correlations between root length and root respiration rate. These results imply that reducing the metabolic cost (= root respiration rate) is a key mechanism for root plasticity expression, which CSSL50 showed under mild drought.

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Incidence and Intensity of Root Disease Complex due to Nematode and Soilborne Fungal Pathogens in Mulberry (Morus alba L.)

  • Naik, Vorkady Nishitha;Sharma, Dinesh Dutta;Govindaiah, Govindaiah
    • International Journal of Industrial Entomology and Biomaterials
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    • v.16 no.2
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    • pp.49-56
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    • 2008
  • A preliminary survey on the incidence and intensity of root disease complex (association of Meloidogyne incognita and root rot pathogens) was carried out in the sericultural areas of Karnataka. A total of 280 mulberry gardens were surveyed in 14 districts of Karnataka belonging to different types of soil (red sandy, red loamy and black cotton), farming systems (irrigated and rainfed), varieties (V-1, K-2, Local and S-13) and age of the plants (0-5, 5-10 and 10-15 years). It was observed that the association of M. incognita with Botryodiplodia theobromae and Fusarium solani causes the root disease complex in mulberry. Of the 280 gardens visited, 94 were infested with the disease complex and incidence was recorded as 33.6%. The higher intensity of root disease complex was observed when the root system had more than 100 galls/plant with infection of mixed population of B. theobromae and F. solani in sandy soil under irrigated farming. The 5-10 years old mulberry plantation with V-I variety was found to be most susceptible to root disease complex. Districts like Mysore, Kolar, Mandya, Tumkur, Chitradurga and Bangalore were observed as sensitive areas. Further, the wounds caused by M. incognita in mulberry roots favour the easy entry of root rot pathogens, which increased the severity of the disease very fast.

MFM-based alarm root-cause analysis and ranking for nuclear power plants

  • Mengchu Song;Christopher Reinartz;Xinxin Zhang;Harald P.-J. Thunem;Robert McDonald
    • Nuclear Engineering and Technology
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    • v.55 no.12
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    • pp.4408-4425
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    • 2023
  • Alarm flood due to abnormality propagation is the most difficult alarm overloading problem in nuclear power plants (NPPs). Root-cause analysis is suggested to help operators in understand emergency events and plant status. Multilevel Flow Modeling (MFM) has been extensively applied in alarm management by virtue of the capability of explaining causal dependencies among alarms. However, there has never been a technique that can identify the actual root cause for complex alarm situations. This paper presents an automated root-cause analysis system based on MFM. The causal reasoning algorithm is first applied to identify several possible root causes that can lead to massive alarms. A novel root-cause ranking algorithm can subsequently be used to isolate the most likely faults from the other root-cause candidates. The proposed method is validated on a pressurized water reactor (PWR) simulator at HAMMLAB. The results show that the actual root cause is accurately identified for every tested operating scenario. The automation of root-cause identification and ranking affords the opportunity of real-time alarm analysis. It is believed that the study can further improve the situation awareness of operators in the alarm flooding situation.

A review of contemporary issues in obturation

  • Jung, Il-Young
    • Proceedings of the KACD Conference
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    • 2001.11a
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    • pp.570-570
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    • 2001
  • Complete obturation of the root canal system, with a dimensionally stable material, is a goal in conventional root canal therapy. However, there have been a multitude of empiric opinions regarding the root canal obturation. The purpose of this presentation was to review the various issues on canal obturation.(omitted)

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Effects of Media and Growth Regulators on the Growth and Saponin Production of Ginseng Root (인삼 Root의 생장 및 사포닌 생성에 미치는 배지와 생장조절물질의 영향)

  • 김정혜;장은정;오훈일
    • Journal of Ginseng Research
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    • v.25 no.3
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    • pp.130-135
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    • 2001
  • Effects of media and growth regulators on the growth and saponin accumulation of ginseng root were investigated to develop the ginseng root culture system. When Panax ginseng C. A. Meyer roots were induced and cultured in various liquid media, the maximum root growth and saponin production were obtained in SH medium and an initial doubleing time of ginseng root was approximately 10 days. The patterns and contents of ginsenosides of cultured ginseng root in various media were different from each other. SH and White media resulted in higher total ginsenosides contents than the other media. Among different combinations and concentrations of growth regulators, SH medium containing 4.0mg/ L NAA gave best growth of ginseng roots, while saponin content was highest in SH medium containing 0.5mg/L BAP. These results suggested that the rapid production of ginseng saponin is possible by root culture of Panax ginseng.

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