• Title/Summary/Keyword: Cylindric

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Powdery Mildew on Broad Bean (Vicia faba) Caused by Oidium sp. in Korea (Oidium sp.에 의한 잠두 흰가루병 발생)

  • 권진혁;강수웅;박창석
    • Research in Plant Disease
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    • v.7 no.2
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    • pp.120-122
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    • 2001
  • The powdery mildew of broad bean (Vicia faba) extensively occurred in farmers' fields in Changseon-myon, Namhae-gun, Gyeongsangnam-do, Korea in 2001. Both sides of the leaves and stems were covered with white fungal spores and mycelia, and then the leaves and stems colored brown and dark brown and eventually died. Conidia and conidiophores were formed on the lesion. Conidia were cylindric, 29~45$\times$13~23 um (av, 36~18 um) in size and born singly on the conidiophore. Fibrosin bodies were not observed. Conidiophores were straight with 3-4 cylindric cells and 51~100$\times$6~10 um (av.70$\times$8 um) in size. Foot cell was 28~53$\times$7~10 um (av,39$\times$8 um) in size. Appressorium was a lobed type. Cleistothecia were not formed. This is the first report on powdery mildew of broad bean caused by Oidium sp. in Korea.

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Powdery Mildew on Phlox Caused by Oidium sp. in Korea (Oidium sp.에 의한 풀협죽도 흰가루병 발생)

  • Kwon, Jin-Hyeuk;Park, Chang-Seuk
    • The Korean Journal of Mycology
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    • v.31 no.1
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    • pp.50-52
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    • 2003
  • The powdery mildew of Phlox (Phlox paniculata) extensively occurred in the experimental farm of Cheongam-myon, Hadong-gun, Gyeongnam province in 2002. Both sides of the leaves and stems were covered with the white fungal spores and mycelia, and then the leaves became brown to dark brown in color, eventually died. The conidiophores on the lesion were observed. Conidia were cylindric in shape, colorless, $25.3{\sim}49.4{\times}12.3{\sim}17.2{\mu}m$ in size and borne singly on conidiophore. Fibrosin bodies were not observed. Conidiophores were straight with 2-4 cylindric cells, and $65.7{\sim}124.8{\mu}m$ in size. Appressoria were lobed. Cleistothecia were not formed. This is the first report on powdery mildew of Phlox caused by Oidium sp. in Korea.

New Application of Endosseous Implants - Implant Mediated Drug Delivery System(IMDDS) (임상가를 위한 특집 3 - 임플란트의 새로운 응용 - 임플란트 매개 약물 전달 시스템)

  • Park, Young-Seok;Lee, Shin-Jae;Hwang, Chee Il
    • The Journal of the Korean dental association
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    • v.52 no.9
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    • pp.550-557
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    • 2014
  • The restorative treatment with dental implants in edentulous patients has been a well documented treatment modality proven in experimental studies and long-term clinical investigations. The aim of this paper is to introduce the implant mediated drug delivery system as a novel application of endosseous implants. The system is composed of hollow cylindric implants which has multiple microholes for drug delivery. For this purpose, the general outlines of drug delivery system and drug delivery route is discussed briefly. In addition, this paper deals with the results of experiments done up to now and the future perspective of the system.

Chloride Penetration in Circular Concrete Columns

  • Morga, M.;Marano, G.C.
    • International Journal of Concrete Structures and Materials
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    • v.9 no.2
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    • pp.173-183
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    • 2015
  • Most of the diffusion models of chloride ions in reinforced concrete (RC) elements proposed in literature are related to an isotropic homogeneous semi-infinite medium. This assumption reduces the mathematical complexity, but it is correct only for plane RC elements. This work proposes a comparison between the diffusion model of chloride ions in RC circular columns and in RC slab elements. The durability of RC cylindric elements estimated with the circular model instead of the plane model is shown to be shorter. Finally, a guideline is formulated to properly use the standard and more simple plane model instead of the circular one to estimate the time to corrosion initiation of cylindrical RC elements.

Persimmon Gray Mold Caused by Botrytis cinerea (Botrytis cinerea에 의한 감나무 잿빛곰팡이병)

  • 권진혁;강수웅;경상대
    • Plant Disease and Agriculture
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    • v.5 no.1
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    • pp.55-57
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    • 1999
  • Botrytis cinerea was isolated from a gray mo이 leaf lesion on persimmon in fields of Kyeonsangnam-do from 1996 to 1998, and etiological study was conducted including physiological characteristics. It formed gray mold lesion with light green color on leaves of persimmon (Diospyros kaki). The temperature range for mycelial growth was between $5^{\circ}C$ and $30^{\circ}C$ with the optimum temperatures of $20^{\circ}C$ to $25^{\circ}C$. Conidia were oviod, cylindric, and colorless and their dimensions in culture were $8.4~11.5\times7.0~8.9\mu\textrm{m}$. The optimum temperature of conidial germination was $25^{\circ}C$. Sclerotia on potato dextrose agar medium were well formed and brownish condiophores were observed with their size of $18.5~64.9\times4.5~8.0\mu\textrm{m}$. Symptoms on artificially inoculated plants were similar to those of gray mold disease on persimmon caused by Botrytis cinerea in fields.

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A Study on the improvement of element division of hydrid integral method for analyzing of the offshore structures (해양구조물의 동요해석을 위한 Hybrid적분방정식법의 요소분할 개선에 관한 연구)

  • Lee, Sang-Yeob
    • Journal of the Korean Society of Industry Convergence
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    • v.2 no.2
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    • pp.3-10
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    • 1999
  • Recently, It is proceeding the project of offshore structures in the many contury. A hybrid boundary-integral method is developed for computing wave forces on floating bodies. In this method, using the cylindric boundary for deviding elements, it is convenient to analysis but is difficult to apply to the rectangular or slender bodies. Thus, in this paper, I propose the new method by using the fictitious vertical cylinder of arbitary cross-section and shows results of the numerical analysis for testing.

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Mobile Robot Navigation For Recovering Local Minimum Using Ultrasonic Sensor (초음파센서를 이용한 이동 로봇의 지역 최소 회복을 위한 주행 알고리즘)

  • Myung, Ki-Ho;Yang, Dong-Hoon;Yoo, Young-Dong;Hong, Suk-Kyo
    • Proceedings of the KIEE Conference
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    • 1999.07g
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    • pp.3086-3088
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    • 1999
  • An ultrasonic sensor is one of most popular sensor used to navigate mobile robots within environments containing obstacles. But many navigation algorithm have studied because of the drawback of ultrasonic sensor such that poor directionality, frequent misreadings, specular reflections. Also, the most crucial drawback of this algorithm, that is VFF, VFM, EDM, PFM, WFM, GFM etc. has been that the mobile robot may become trapped in a local minimum. In this paper, we present a theoretical study of a navigation algorithm which integrals a heuristic-search local minimum (or trap) recovery method with a vector-field based method to maneuver cylindric mobile robots in unknown of unstructured environments. Also, an autonomous mobile robot uses dead-reckoning to estimate the current position and orientation of a mobile robot.

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A Sensorless Speed Control of Cylindric;31 Permanent Magnet Synchronous Motor using an Adaptive Integral Binary Observer (적응 적분바이너리 관측기를 이용한 원통형 영구자석 동기전동기의 센서리스 속도제어)

  • 최양광;김영석;한윤석
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.53 no.3
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    • pp.152-163
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    • 2004
  • This paper presents a sensorless speed control of cylindrical permanent magnet synchronous motors(PMSM) using an adaptive integral binary observer In view of composition with a main loop regulator and an auxiliary loop regulator, the binary observer has a property of the chattering alleviation in the constant boundary layer. However, the steady state estimation accuracy and robustness are dependent upon the width of the constant boundary. In order to improve the steady state performance of the binary observer, the binary observer is formed by adding extra integral dynamics to the switching hyperplane equation. With the help of integral characteristic, the rotor speed can be finely estimated and utilized for a sensorless speed controller for PMSM. Since the Parameters of the dynamic equations such as machine inertia or a viscosity friction coefficient are lot well known, there are many restrictions in the actual implementation. The proposed adaptive integral binary observer applies an adaptive scheme so that observer may overcome the problem caused by using the dynamic equations and the rotor speed is constructed by using the Lyapunov function. The observer structure and its design method are described. The experimental results of the proposed algorithm are presented to demonstrate the effectiveness of the approach.

A Study on the Reduction of Soil Particle Dissociation Rate by the Root of 'Salix Gracilistyla' (갯버들 근계의 토양 입자 해리 억제효과에 관한 연구)

  • Lee, Chun-Seok;Park, Myung-Ahn;Kang, Ho-Chul
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.6 no.3
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    • pp.69-78
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    • 2003
  • The main purpose of this study was to verify the shore margin protection effect of the root system of Salix gracilistyla Miq. developed from direct sticking cuttings on wetland, focusing on the effect of the root system reducing soil particle dissociation rate in water. The soil dissociation rate was examined through slaking tests with cylindric pure soil column at maximum particle density and the same size column of root reinforced soil. The dry weight of remained soil was measured after 5, 10, 15, 30minutes and 1, 6, 12, 24, 48hours inundation. As results, the soil particles began to dissociate severely at 10 minutes and only 10% of soil particles were left after 25minutes inundation. The stable slope angle of pure soil was $36^{\circ}$after 24 hours. On the other hand, the columns of root reinforced soil were stable even after 24hours, being dissociated only 7.2% of soil particles. So, it was revealed that the root system was very effective materials protecting more than 80% of soil particle from dissociation in inundation.

Numerical analysis of fracture mechanisms for porous calcium phosphate (다공성 칼슘포스파이트에 대한 파괴분석)

  • Park, Jin-Hong;Bae, Ji-Yong;Shin, Jae-Bum;Jeon, In-Su
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1301-1302
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    • 2008
  • In this study, the fracture strength for fracture mechanism porous calcium phosphate made from sintered with ${\beta}$-tricalcium phosphate obtained by wet precipitation procedure is analyzed using finite element method and experiment measurement. First, three $3{\times}3{\times}3mm^3$ and $5{\times}5{\times}5mm^3$ specimens are prepared and tomographic images of one $5{\times}5{\times}5mm^3$ specimen are obtained by micro focus X-ray CT. The compression tests using the specimens are carried out to measure the elastic modulus and fracture strength to analyze the fracture mechanism of porous calcium phosphate specimen. The tomographic images are reconstructed by 3D reconstruction program. The finite elements are directly built up in the reconstructed specimen. The numerical simulation for the compression tests is performed using the element. The mechanism of calcium phosphate of simulation are obtained by the compression tests using there cylindric specimen of height 19.5 mm and diameter 10 mm. From the results, the applicability of porous calcium phosphate is evaluated to care fracture and vacant bone of a patient as the reinforcement material.

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