• Title/Summary/Keyword: Loop adding

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Development and Evaluation of Loop-Mediated Isothermal Amplification Assay for Rapid Detection of Tylenchulus semipenetrans Using DNA Extracted from Soil

  • Song, Zhi-Qiang;Cheng, Ju-E;Cheng, Fei-Xue;Zhang, De-Yong;Liu, Yong
    • The Plant Pathology Journal
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    • v.33 no.2
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    • pp.184-192
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    • 2017
  • Tylenchulus semipenetrans is an important and widespread plant-parasitic nematode of citrus worldwide and can cause citrus slow decline disease leading to significant reduction in tree growth and yield. Rapid and accurate detection of T. semipenetrans in soil is important for the disease forecasting and management. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed to detect T. semipenetrans using DNA extracted from soil. A set of five primers was designed from the internal transcribed spacer region (ITS1) of rDNA, and was highly specific to T. semipenetrans. The LAMP reaction was performed at $63^{\circ}C$ for 60 min. The LAMP product was visualized directly in one reaction tube by adding SYBR Green I. The detection limit of the LAMP assay was $10^{-2}J2/0.5g$ of soil, which was 10 times more sensitive than conventional PCR ($10^{-1}J2/0.5g$ of soil). Examination of 24 field soil samples revealed that the LAMP assay was applicable to a range of soils infested naturally with T. semipenetrans, and the total assay time was less than 2.5 h. These results indicated that the developed LAMP assay is a simple, rapid, sensitive, specific and accurate technique for detection of T. semipenetrans in field soil, and contributes to the effective management of citrus slow decline disease.

A Research for Improvement of WIM System by Abnormal Driving Patterns Analysis (비정상 주행패턴 분석을 통한 WIM 시스템 개선 연구)

  • Park, Je-U;Kim, Young-Back;Chung, Kyung-Ho;Ahn, Kwang-Seon
    • Journal of Internet Computing and Services
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    • v.11 no.4
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    • pp.59-72
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    • 2010
  • WIM(Weigh-In-Motion) is the system measuring the weight of the vehicle with a high-speed. In the existing WIM system, vehicle weight is measured based on the constant speed and the error ratio has 10%. However, because of measuring the driving pattern, that is abnormal driving pattern which is like the acceleration and down-shift of the drivers, it has the error ratio which is bigger than the real. In order to it reduces the error ratio of WIM system, the improved WIM system needs to find the abnormal driving pattern. In order to reducing the error ratio of these WIM systems, the improved WIM system can find abnormal driving patterns. In this paper, the improved WIM system which analyzes the abnormality driving pattern influencing on the error ratio of WIM system of an existing and minimizes the error span is designed. The improved WIM system has the multi step loop structure of adding the loop sensor to an existing system. In addition, the measure function defined as an intrinsic is improved and the weight measured by the abnormal driving pattern is amended. The analysis of experiment result improved WIM system can know the fact that the error span reduces by 8% less than in the existing the maximum average sampling error 22.98%.

Loop-mediated Isothermal Amplification assay for Detection of Candidatus Liberibacter Asiaticus, a Causal Agent of Citrus Huanglongbing

  • Choi, Cheol Woo;Hyun, Jae Wook;Hwang, Rok Yeon;Powell, Charles A
    • The Plant Pathology Journal
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    • v.34 no.6
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    • pp.499-505
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    • 2018
  • Huanglongbing (HLB, Citrus greening disease) is one of the most devastating diseases that threaten citrus production worldwide. Although HLB presents systemically, low titer and uneven distribution of these bacteria within infected plants can make reliable detection difficult. It was known loop-mediated isothermal amplification (LAMP) method has the advantages of being highly specific, rapid, efficient, and laborsaving for detection of plant pathogens. We developed a new LAMP method targeting gene contained tandem repeat for more rapid and sensitive detection of Candidatus Liberibacter asiaticus (CLas), putative causal agent of the citrus huanglongbing. This new LAMP method was 10 folds more sensitive than conventional PCR in detecting the HLB pathogen and similar to that of real-time PCR in visual detection assay by adding SYBR Green I to mixture and 1% agarose gel electrophoresis. Positive reactions were achieved in reaction temperature 57, 60 and $62^{\circ}C$ but not $65^{\circ}C$. Although this LAMP method was not more sensitive than real-time PCR, it does not require a thermocycler for amplification or agarose gel electrophoresis for resolution. Thus, we expect that this LAMP method shows strong promise as a reliable, rapid, and cost-effective method of detecting the CLas in citrus and can be applied for rapid diagnosis is needed.

An Optical Disk Drive Servo System Using a Modified Disturbance Observer (수정된 외란관측기를 이용한 광 디스크 드라이브 서보 시스템)

  • Jeong Jong-Il;Kim Moo-Sub;Oh Kyung-Whan;Chung Chung Choo
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.6
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    • pp.484-491
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    • 2005
  • Using a disturbance observer is effective in enhancing the performance of dynamic system in presence of disturbances. Although various types of disturbance observers have been proposed to improve sensitivity of systems, there exist poor transient responses due to cross-couplings among disturbance observer loops. In this paper, dual disturbance observer (DOB) is proposed to reduce the effects of the cross-couplings. A different type of loop transfer function is proposed for external disturbance observer. While improving the sensitivity function by adding external DOB, it also provides improved complementary sensitivity function. The proposed dual DOB is applied to a commercial optical disk drive tracking system. It is shown that the dual DOB is an effective method in rejecting the effect of disturbance as well as improving the tracking performance.

Dual Buck Half-Bridge Inverter with Zero Voltage Switching (ZVS를 이용한 DB하프브리지 인버터 구현 방법)

  • Park, Chong-Yun;Lim, Ki-Seung;Sin, Dong-Seok;Choe, Hyeon-Hui
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.4
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    • pp.756-762
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    • 2009
  • This paper proposes a high efficient Dual Buck Inverter design with a zero voltage switching (ZVS) control technique. The ZVS control is realized by adding a feedback loop circuit which is implemented by simple RS latch and TTL gate. The used load was 200W -Ceramic Metal Halide Lamp. The experimental results show that the proposed Inverter system could avoid the acoustic resonance and achieve high efficiency by Zero Voltage Switching.

The High Performance of a Output Voltage in 3-phase PWM Converter (3상 PWM 콘버어터의 출력전압 속응제어)

  • Yong, Hong-Taek;Cho, Sun-Bong;Hyun, Dong-Seok
    • Proceedings of the KIEE Conference
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    • 1992.07b
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    • pp.992-994
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    • 1992
  • Diode rectifier has many low order harmonics in line currents. So, power factor of input side is relatively low. Recently, PWM conveters have been actively studied in order to reduce the harmonics. This paper describes a voltage source PWM rectifier with feed-forward compensation of instantaneous load power. By adding feed-forward compensation to dc link voltage control loop, the fluctuation of dc link voltage at a sudden load change can be considerably suppressed. Simulation based on analytical approach Was performed and the results of it showed a good agreement with theory.

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The PWM Speed Control of DC servo Motor for Movable Robot Drives (자립형 이동로보트 구동을 위한 DC서보전동기 PWM속도제어)

  • Hong, S.I.;Kim, C.J.;Jo, C.J.;Kim, C.W.
    • Proceedings of the KIEE Conference
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    • 1992.07b
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    • pp.1185-1187
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    • 1992
  • In this paper, PWM control is applied to the microprcessor-based adjustable speed dc motor drives. The motor drive system is composed of phase locked loop. Main drive circuit of the system is consisted of H-type bridge with switching transistors. PWM drive circuit is linearized by adding flywheeling diodes. And also. We study the optimum PWM data and period time so that it hase a nearly liner relationship between current and torque.

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Position-Based Force Control Application of a Mobile Robot with Two Arms (두 팔이 달린 이동 로봇의 위치기반 힘 제어응용)

  • Ahn, Jae Kook;Jung, Seul
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.4
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    • pp.315-321
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    • 2013
  • This paper presents the position-based force control application of a mobile manipulator. The mobile manipulator consists of two six DOF manipulators and a mobile robot. Kinematics of the robot is analyzed and simulated to validate the analysis. A position-based force control technique is applied to the robot by adding an outer loop to interact with the environment. Experimental studies of force control applications of robot arm and interaction with a human operator are conducted. Experimental results show that the robot arm is well regulated to follow the desired force.

Self-Tuning Position Control of a Remotely Operated Vehicle (원격무인 잠수정의 자기동조 위치제어)

  • Lee, Pan-Muk
    • Journal of Ocean Engineering and Technology
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    • v.3 no.2
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    • pp.551-551
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    • 1989
  • In general, a remotely operated vehicle(ROV) operates at deep sea. The control system of ROV is composed of two local loops; the first loop placed on the surface vessel monitors and manipulates the attitude of the ROV using joystick, and the second part on the ROV automatically controls thrusters and acquires positional data. This paper presents a position control simulation of a ROV using an adaptive controller and discusses the control effects of two different conditions. The design of an adaptive control system is obtained by the application of a self-tuning controller with the minimization of an appropriate cost function. The parameters of the control system are estimated by a recursive least square method(RLS). In the simulation, a Runge-Kutta method is used for the numerical integration and the generated outputs are obtained by adding measurement errors. Additionally, this paper discusses the mathematical modelling of a ROV and make a survey of control systems.

Self-Tuning Position Control of a Remotely Operated Vehicle (원격무인 잠수정의 자기동조 위치제어)

  • Lee, Pan-Muk
    • Journal of Ocean Engineering and Technology
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    • v.3 no.2
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    • pp.51-58
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    • 1989
  • In general, a remotely operated vehicle(ROV) operates at deep sea. The control system of ROV is composed of two local loops; the first loop placed on the surface vessel monitors and manipulates the attitude of the ROV using joystick, and the second part on the ROV automatically controls thrusters and acquires positional data. This paper presents a position control simulation of a ROV using an adaptive controller and discusses the control effects of two different conditions. The design of an adaptive control system is obtained by the application of a self-tuning controller with the minimization of an appropriate cost function. The parameters of the control system are estimated by a recursive least square method(RLS). In the simulation, a Runge-Kutta method is used for the numerical integration and the generated outputs are obtained by adding measurement errors. Additionally, this paper discusses the mathematical modelling of a ROV and make a survey of control systems.

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