• Title/Summary/Keyword: on-off control

Search Result 2,536, Processing Time 0.031 seconds

Design on Optimum Control of Subthreshold Current for Double Gate MOSFET (DGMOSFET에서 최적의 서브문턱전류제어를 위한 설계)

  • Jung, Hak-Kee;Na, Young-Il;Lee, Jong-In
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • v.9 no.2
    • /
    • pp.887-890
    • /
    • 2005
  • The double gate(DG) MOSFET is a promising candidate to further extend the CMOS scaling and provide better control of short channel effect(SCE). DGMOSFETs, having ultra thin updoped Si channel for SCEs control, are being validated for sub-20nm scaling, A channel effects such as the subthreshold swing(SS), and the threshold voltage roll-off(${\Delta}V_{th}$). The propsed model includes the effects of thermionic emission and quantum tunneling of carriers through the source-drain barrier. The proposed model is used to design contours for gate length, channel thickness, and gate oxide thickness.

  • PDF

Stabilization of elevation for gunner primary sight using variable structure control (가변구조제어에 의한 조준경 고각 안정화)

  • 김중완;이정규;김주상;이만형
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1990.10a
    • /
    • pp.643-647
    • /
    • 1990
  • Gunner primary sight(GPS) stabilization system lays line of sight(LOS) to find out a target and transmits informations to the fire control system (FCS). In a moving vehicle, accuracy of LOS and FCS depends on the design of GPS and servomechanism system. The heavy vibration of vehicle on the severe off-road environment degenerates the stabilization capability of GPS. In this study, to stabilize of elevation for GPS using the variable structure control, we derived the dynamic equation of GPS system and designed the variable structure controller. Computer simulation results fulfilled the static and dynamic stability of GPS using the variable structure control.

  • PDF

Development of an Environmental Control System for Agricultural Storage Facility (상온저장 시설의 환경 제어 시스템 개발)

  • 임종환;현명택
    • Food Science and Preservation
    • /
    • v.4 no.2
    • /
    • pp.101-113
    • /
    • 1997
  • Temperature, relative humidity and ventilation are closely related one another, and they are the main factors to be controlled for the environmental control system of a storage facility. Conventional environmental control systems do not consider the interrelationship between temperature, relative humidity and ventilation, which results in low performance and high energy consumption. To overcome the inefficiency of the conventional ones, it was developed an on-off control system based on the interrelationship between the factors. The usefulness of the system was illustrated with the results produced by a set of experiments in a real world.

  • PDF

SCARA robot calibration on off-line programming (오프라인 프로그래밍에서 스카라 로봇의 보정)

  • Jung, Sung-Woo;Son, Kwon;Lee, Min-Chul;Choi, Jae-Won
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1997.10a
    • /
    • pp.1832-1835
    • /
    • 1997
  • Off-line programming systems are widely spread in assembly lines of minute electronic products to huge offshore structures. Any OLP system has to be calibrated before the on-line robot tasks are performed because there are inherent differences between the CAD model on OLP and the real robot workspace. This paper uses simple geometric expressions to propose a calibration method applicable to an OLP for SCARA robots. A positioning task on the two-dimensional horizontal surface was used in the error analysis of a SCARA robot and the anaysis shows that the inaccuracy results from the two error sources non-zero offset angles of two rotational joints at the zero return and differences in link lengths. Pen marks on a sheet of plotting paper are used to determine the accurate data on the joint centers and link dimensions. The calculated offset angles and link lengths are fed back to the OLP for the calibration of the CAD model of the robot and task environments.

  • PDF

Numerical Study on Characteristics and Control of Heading Angle of Floating LNG Bunkering Terminal for Improvement of Loading and Off-loading Performance

  • Oh, Seunghoon;Jung, Dong-Woo;Kim, Yun-Ho;Kwak, Hyun-Uk;Jung, Jae-Hwan;Jung, Sung-Jun;Park, Byeongwon;Cho, Seok-Kyu;Jung, Dongho;Sung, Hong Gun
    • Journal of Ocean Engineering and Technology
    • /
    • v.34 no.2
    • /
    • pp.77-88
    • /
    • 2020
  • In this study, heading characteristics and heading control performances were evaluated to achieve the wave shield effect. The wave shield effect originating from heading control reduces the relative motions of moored vessels in a floating liquefied natural gas bunkering terminal (FLBT). Therefore, loading and off-loading performances are improved through reduced relative motion. For the objective of this study and efficiency of the analysis, a simplified model was used that assuming no relative motion of the moored vessels in the FLBT. The simplified model involved modeling the environmental loads and inertia of several floating bodies, including FLBT, into the environmental loads and inertia of a single vessel. The simplified model was validated through comparisons with model tests. With the simplified model, heading characteristics and heading control simulations were performed using low-frequency planar motion equations. The heading characteristics and heading control performances of FLBT were analyzed through the results of simulations under the expected environmental conditions. The capacity of the tunnel thrust for the heading control performance was confirmed to be adequate for improvement of the loading and off-loading performances using the wave shielding effects under the operation conditions.

Isolation and Identification of Burkholderia pyrrocinia CH-67 to Control Tomato Leaf Mold and Damping-off on Crisphead Lettuce and Tomato

  • Lee, Kwang-Youll;Kong, Hyun-Gi;Choi, Ki-Hyuck;Lee, Seon-Woo;Moon, Byung-Ju
    • The Plant Pathology Journal
    • /
    • v.27 no.1
    • /
    • pp.59-67
    • /
    • 2011
  • A bacterial strain CH-67 which exhibits antagonism towards several plant pathogenic fungi such as Botrytis cinerea, Fulvia fulva, Rhizoctonia solani, Sclerotinia sclerotiorum, Colletotrichum sp. and Phytophthora sp. was isolated from forest soil by a chitin-baiting method. This strain was identified as Burkholderia cepacia complex (Bcc) and belonging to genomovar IX (Burkholderia pyrrocinia) by colony morphology, biochemical traits and molecular method like 16S rRNA and recA gene analysis. This strain was used to develop a bio-fungicide for the control of tomato leaf mold caused by Fulvia fulva. Various formulations of B. pyrrocinia CH-67 were prepared using fermentation cultures of the bacterium in rice oil medium. The result of pot experiments led to selection of the wettable powder formulation CH67-C containing modified starch as the best formulation for the control of tomato leaf mold. CH67-C, at 100-fold dilution, showed a control value of 85% against tomato leaf mold. Its disease control efficacy was not significantly different from that of the chemical fungicide triflumidazole. B. pyrrocinia CH-67 was also effective in controlling damping-off caused by Rhizoctonia solani PY-1 in crisphead lettuce and tomato plants. CH67-C formulation was recognized as a cell-free formulation since B. pyrrocinia CH-67 was all lethal during formulation process. This study provides an effective biocontrol formulation of biofungicide using B. pyrrocinia CH-67 to control tomato leaf mold and damping-off crisphead lettuce and tomato.

A Controller test for the Attitude Control of a sounding Rocket using a Testbed (평가장치를 이용한 과학 로켓 자세 제어기 테스트)

  • 전상운;공현철
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.189-189
    • /
    • 2000
  • A controller test on a sounding rocket using a testbed is discussed in the paper. Because of the high cost and the risk for the flight test the hardware simulation on the ground is performed. In this paper the conventional On/Off Controller is applied to the attitude control of a sounding rocket. The hardware simulation results are compared with those of the software simulation.

  • PDF

CAD Based Robot Off-line Programming for Shoe Adhesive Application System (신발 접착제 도포 시스템을 위한 CAD 기반 로봇 오프라인 프로그래밍)

  • 윤중선;차동혁;김진영
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.10 no.7
    • /
    • pp.643-648
    • /
    • 2004
  • Most of shoes manufacturing processes are not yet automated, which puts restrictions on the increase of productivity. Among them, adhesive application processes particularly are holding the most workers and working hours. In addition, its working conditions are very poor due to the toxicity of adhesive agents. In case of automating adhesive application processes by using robots, the robot teaching by playback is difficult to produce high productivity because the kinds of shoes to be taught mount up to several thousands. Therefore, it is essential to generate the robot working paths automatically according to the kind, the size, and the right and left of shoes, and also to teach them to the robot automatically. This study deals with automated adhesive spraying to shoe outsoles and uppers by using a robot, and develops the program to generate three-dimensional robot working paths off-line based on CAD data. First, the three-dimensional data of an outsole outline or an upper profiling line are extracted from the two-dimensional CAD drawing file or the three-dimensional scanner. Next, based on the extracted data and the nozzle conditions for adhesive spraying, a robot working path is generated automatically. This research work is the core in automating adhesive spraying processes, and will do much for increasing productivity of shoes manufacturing.

Integrated Management of Process Schedule and Quantity Take-Off for Steel Structures using BIM Information (BIM정보를 활용한 강구조물의 공정 물량 통합관리)

  • Kim, Jin-Uk;Shin, Tae-Song
    • Journal of KIBIM
    • /
    • v.8 no.2
    • /
    • pp.10-18
    • /
    • 2018
  • BIM technologies store, share and integrate the information produced in each sector of the construction industry. From this point on, it increases the efficiency of the work. Currently, quantity take-off and process schedule are derived separately based on BIM technology. When calculating the quantity by process, relevant information shall be collected, reinterpreted, and reevaluated as required by the practice. The purpose of this study is to develop an integrated process and quantity management system through BIM collaboration and to build prototypes for steel structures. The main research is to build a construction BIM model for steel structures and a process BIM model through BIM collaboration. Furthermore, necessary information was selected and processed according to the user's needs for integrated management. Relevant integration outcomes are visualized graphically to maximize utilization. Through these studies, a system for integrated control of processes and supplies is provided, and the results are expected to contribute to the improvement of working efficiency and are easily and quickly reflected in design change and process change. In this study, we intended to enhance the usability of information by linking process schedules with quantity calculations based on BIM. Thus, the process for integrated control of the quantity of structural components by process unit and the BIM based schedule information was established. In addition, the efficiency of the information link of the integrated management system was considered for design changes and process schedule changes.

Development of Tire Test Bed for Dynamic Behavior Analysis of Vehicles on Off-roads (비포장노면 차량 거동 분석을 위한 타이어 테스트베드 개발)

  • Lee, Dae-Kyung;Sohn, Jeong-Hyun
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.21 no.3
    • /
    • pp.29-35
    • /
    • 2022
  • When a vehicle is driven off a road surface, the deformations of the road surface and tire are combined. Consequently, the dynamic behavior of wheel movement becomes difficult to predict and control. Herein, we propose a tire test bed to capture the dynamic behavior of tires moving on sand and soil. Based on this study, it is discovered that the slip rate can be controlled, and the vertical force can be measured using a load cell. The test results show that this test bed can be useful for capturing the dynamic behavior of the tire and validating dynamic simulations. In fact, the tire test bed developed in this study can be used to verify the results of computer simulations. In addition, it can be used for basic experiments pertaining to the speed control of unmanned autonomous vehicles.