• Title/Summary/Keyword: high isolation

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Isolation and Characterization of Chloroplast DNA in Korea Ginseng, Panax gindeng C.A. Meyer (고려인삼(Panax ginseng C.A. Meyer)의 엽록체 DNA 분리 및 특성조사)

  • Lee, Jeong-Heon;Lim, Yong-Pyo;Choi, Kwang-Tae
    • Journal of Ginseng Research
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    • v.17 no.1
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    • pp.39-44
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    • 1993
  • In Korean ginseng, Panax ginseng C.A Meyer, it was difficult to isolate chloroplast DNA with classical methods, because of the high polysaccharide content of ginseng chloroplast The simple and efficient method of chloroplast DNA isolation from ginseng leaves has been developed by motificalion of recently advanced methods. Also, it can be successfully applied to ctDNA isolation of Chinese cabbage, radish, petunia tobacco as well as ginseng. Isolated chloroplast DNA from ginseng was digested with various restriction endonucleases. It was estimated that the molecular weight of Korean ginseng chloroplast DNA was about 142 kb. There was no difference in restriction endonuclease digestion patterns between two variants of Korean ginseng, which are Jakyung-Jong (violet-stem variant) and Hwang- sook-Jong (yellow-berry variant).

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Design of the Open-Loop Combined Meandered-Line 1-Layer Radiator for Diversity Antennas with Size-Reduction and Improved Isolation (다이버시티 안테나의 소형화와 격리도 향상을 위한 미앤더 선로와 개방형 루프가 결합된 방사구조의 설계)

  • Mok, Se-Gyoon;Kahng, Sung-Tek;Kim, Yong-Jin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.1
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    • pp.110-116
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    • 2012
  • This paper proposes a new diversity antenna which is the base of MIMO, tunable and reconfigurable antennas. The antenna has a small size and high inter-antenna isolation resulting from the compact radiating element comprising a meandered line and an open-loop combined in one limited uniplanar space and a modified T-shaped decoupling structure, respectively. In a WiMAX band, the radiating element and the entire antenna are $0.092{\lambda}$ and $0.2216{\lambda}$ in size, which shows effective size-reduction and the gain and efficiency of the proposed antenna attached to the ground of a handheld device are 3.7dBi and 56% acceptable to the industrial standard.

Base-isolated building with high-damping spring system subjected to near fault earthquakes

  • Tornello, Miguel Eduardo;Sarrazin, Mauricio
    • Earthquakes and Structures
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    • v.3 no.3_4
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    • pp.315-340
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    • 2012
  • There are many types of seismic isolation devices that are being used today for structural control of earthquake response in buildings. The most commonly used are sliding bearings and elastomeric bearings, the latter with or without lead core. An alternative solution is the use of steel springs combined with viscoelastic fluid dampers, which is the case discussed in this paper. An analytical study of a three-story building supported on helical steel springs and viscoelastic fluid dampers, GERB Control System (GCS), subjected to near-fault earthquakes is presented. Several earthquakes records have been obtained by the acceleration network installed in the isolated building and in its non-isolated twin since they were finished. These experimental results are analysed and discussed. The aim is to show that the spring-based system can be an alternative for base isolation of small building located near active faults.

Seismic analysis and modeling of isolated elevated liquid storage tanks

  • Seleemah, Ayman A.;El-Sharkawy, Mohamed
    • Earthquakes and Structures
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    • v.2 no.4
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    • pp.397-412
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    • 2011
  • In this paper, the seismic response of elevated broad and slender liquid storage tanks isolated by elastomeric or sliding bearings was investigated. The accuracy of predictions of SAP2000 vs. 3D-BASIS-ME programs was examined. A comparative study of the performance of base isolated tanks when isolation bearings are placed at the top or at the bottom of the supporting tower structure was conducted. It was found that base isolation is quite effective in reducing the earthquake response of elevated liquid storage tanks in which high reductions of base shear and shaft displacement were achieved. Modeling the isolated tanks in SAP2000 was very successful in producing results that are nearly identical to those of program 3D-BASIS-ME. Placing the isolators at the top of the shaft in elevated tanks proved to be much better than placing them at the bottom.

Smart passive control of buildings with higher redundancy and robustness using base-isolation and inter-connection

  • Murase, Mitsuru;Tsuji, Masaaki;Takewaki, Izuru
    • Earthquakes and Structures
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    • v.4 no.6
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    • pp.649-670
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    • 2013
  • It is known that a base-isolated building exhibits a large response to a long-duration, long-period wave and an inter-connected system without base-isolation shows a large response to a pulse-type wave. To compensate for each deficiency, a new hybrid passive control system is investigated in which a base-isolated building is connected to another building (free wall) with oil dampers. It is demonstrated that the present hybrid passive control system is effective both for pulse-type ground motions and long-duration and long-period ground motions and has high redundancy and robustness for a broad range of disturbances.

A Teleoperated Cleaning Robot for a High Radioactive Environment

  • Kim, Ki-Ho;Park, Jang-Jin;Yang, Myung-Seung;Oh, Chae-Youn
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.849-854
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    • 2003
  • The Korea Atomic Energy Research Institute has developed a teleoperated cleaning robot for use in the radioactive zone of the isolation room of the Irradiated Material Examination Facility where direct human access to the interior is strictly limited. The teleoperated cleaning robot that was designed to completely eliminate human interaction with the hazardous radioactive contaminants has five remotely replaceable submodules - a mobile module for navigation, a cleaning module for dislodging and sucking contaminated waste, a sensing module for obstacle avoidance, a collection module for storing the acquired waste, and a cover module for protecting the collection module. This cleaning robot is capable of cleaning the contaminated floor surface of the isolation room and collecting loose dry spent nuclear fuel debris and other radioactive waste fixed or scattered on the floor surface. The developed cleaning robot is operated either by a manual control or by autonomous control in conjunction with a graphical simulator, by which the human operator can monitor and intervene the robot performing cleanup tasks in the isolation room. In this paper, we present the mechanical and environmental design considerations and development of the teleoperated cleaning robot for radioactive isolation room use. We also demonstrate its mock-up performance test results from the viewpoint of a remote cleanup operation and remote maintenance.

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A High-Isolation MIMO Antenna with Dual-Port Structure for 5G Mobile Phones

  • Yang, Hyung-kyu;Lee, Won-Woo;Rhee, Byung-Ho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.4
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    • pp.1458-1470
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    • 2018
  • In this letter, a new dual-port Multiple-Input Multiple-Output (MIMO) antenna is introduced which has two independent signal feeding ports in a single antenna element to achieve smaller antenna volumes for the 5G mobile applications. The dual-port structure is implemented by adding a cross coupled semi-loop (CCSL) antenna as the secondary radiator to the ground short of inverted-F antenna (IFA). It is found that the port to port isolation is not deteriorated when an IFA and CCSL is combined to form a dual-port structure. The isolation property of the proposed antenna is compared with a polarization diversity based dual-port antenna proposed in the literature [9]. The operating frequency range is 3.3-4.0 GHz which is suitable for places where $4{\times}4$ MIMO systems are supposed to be deployed such as in China, EU, Korea and Japan at the band ${\times}$ (3.3 - 3.8GHz. The measured 6-dB impedance bandwidths of the proposed antennas are larger than 700 MHz with isolation between the feeding ports higher than 18 dB [1-2]. The simulation and measurement results show that the proposed antenna concept is a very promising alternative for 5G mobile applications.

Trends of the vibration isolation system for spacecrafts (진동절연 시스템의 위성체 적용 동향)

  • Park, Jong-Seok;Yang, Koon-Ho
    • Current Industrial and Technological Trends in Aerospace
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    • v.8 no.2
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    • pp.54-64
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    • 2010
  • A spacecraft contends with various vibration from the launch to the on-orbit operation, which is one of the major considerations in spacecraft design. The weight reduction has been indispensable to decrease the launch cost, however it produces worse disturbances for the spacecraft equipments. Besides, the load requirements at observation payload interfaces have became severe to secure their pointing stability as their images are required with high resolution. As a possible solution, a vibration isolation system is introduced and it reduces the vibration from the launch vehicle or isolates the spacecraft equipments from their generating/transmitted vibration. In this paper, it is examined the design consideration needed for the accommodation of the vibration isolation systems through the survey of recent applications of vibration mitigation technologies to spacecrafts.

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On-orbit Micro-vibration Isolation Performance Verification for Spaceborne Cryocooler Passive Vibration Isolator Using SMA Mesh Washer (SMA 메쉬 와셔를 적용한 우주용 냉각기 수동형 진동절연기의 궤도 미소진동 절연성능 검증)

  • Kwon, Seong-Cheol;Jeon, Su-Hyeon;Oh, Hyun-Ung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.25 no.1
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    • pp.24-32
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    • 2015
  • Pulse tube-type spaceborne cryocooler is widely used to cool down the infrared sensor of observation satellites. However, such cryocooler also generates micro-vibration which is the one of main sources to seriously affect the image quality during its on-orbit operation. Therefore, to comply with the mission requirement of high resolution observation satellite, additional technical efforts have been required. In this study, we proposed a spaceborne cryocooler passive vibration isolator using SMA mesh washer, which guarantees the structural safety of both the micro-vibration disturbance source and itself under harsh launch vibration loads without an additional holding mechanism and the micro-vibration isolation performance on orbit environment. To verify the micro-vibration isolation performance of the proposed vibration isolator, we performed the micro-vibration isolation measurement test using the dedicated micro-vibration measurement device proposed in this study.

Isolation of Cryphonechia parasitica from Cankers on Chestnut Trees in ]Korea

  • Ju, Young-Jik;Kim, Dae-Hyuk;Cha, Byeong-Jin
    • The Plant Pathology Journal
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    • v.18 no.1
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    • pp.23-29
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    • 2002
  • A total of 672 Cryphonectria parasitica was isolated from 2,536 blight lesions on chestnut twigs, which were collected from major chestnut plantations all over Korea. Isolation rates of each province ranged from 13.5% in Jeonbuk-ds to 37.4% in Gyeongnam-do, with an average rate of 25.6%. The isolates were classified into six groups according to color and shape of colony on PDA: smooth margin (S), irregular margin (I), yellow to brown (Y), white (W), and white with yellow center (C). Among these groups, IY was the most abundant with an isolation rate of 65%. On the other hand, SW, SC, IW, and SY were quite rare, with isolation rates ranging from 1.5% to 5.8%. When the 672 isolates were inoculated on the chestnut twigs,380 isolates (56.5%) caused lesions larger than the standard virulent isolate EPISS-2, while 158 isolates (23.4%) caused smaller lesions than the standard hypovirulent isolate UEP-1. However, 87.4% of the isolates belonged to the virulent group and only 12.6% belonged to the hypovirulent group based on Bavendamm test. In the provinces of Jeonnam-do, Jeonbuk-do, and Gyeongnamdo, which have high density of chestnut trees, the rates of hypovirulent-like isolates were over 20%.