• Horticultural Science & Technology
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• v.29 no.6
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• pp.568-574
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• 2011

Measuring tray as a component in irrigation control system using drainage electrodes was designed and applied for tomato perlite bed culture, and the effectiveness of the irrigation control system was investigated in terms of cultural development and cultivation costs. Five different types of measuring trays equipped with drainage electrodes were tested and the traditional tray was used as the control equipped with time clock. After the first experiment, "Tube-2" was removed because of instability of water content in the substrate. After second experiment, "Tube-1" was removed because of instability of water content in the substrate and low plant yields. In third experiment, "Up-Board" exhibited the best stability in water contents and yields as well as efficiencies in water and fertilizer utilization. The "Up-Board" was the most economical and the easiest system among the tested trays. Therefore, the "Up-Board" system was concluded as the excellent design to apply for the control method using drainage electrodes for tomato perlite bed culture.

• Journal of Satellite, Information and Communications
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• v.9 no.4
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• pp.127-133
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• 2014

In this paper, we present the design, functions and performance analysis of the virtual machine (VM) based on the Lua interpreter for On-Board Control Procedure Execution Environment (OEE). The development of the OEE has been required in order to operate the lunar explorer mission autonomously which is planned by Korea Aerospace Research Institute (KARI) autonomously. The concept of On-Board Control Procedure (OBCP) is already being applied to the deep space missions with a long propagation delay and a limited data transmission capacity since it ensure he autonomy of the mission without the ground intervention. The interpreter is the execution engine in the VM and it interpreters high-level programming codes line by line and executes the VM instructions. So the execution speed is very more slower than that of natively compiled codes. In order to overcome it, we design and implement OEE using register-based Lua interpreter for execution engine in OEE. We present experimental results on a range of additional hardware configurations such as usages of cache and floating point unit. We expect those to utilized to the OBCP scheduling policy and the system with Lua interpreter.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.145-153
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• 2011

In the system necessary for safety such as the train control system, to make train control information be sent correctly is very important to enable organic movement between trains. In the case of the system such as RF-CBTC (Radio Frequency Communication Based Train Control) the control related information is sent through wireless transmission between on-board system of a train and wayside transmitter. The wayside transmitter collects the running information such as location, velocity from the on-board system and operates the optimizing control by sending the control information such as the target, limited velocity to the on-board system. But, when the communication disconnect or train failure, the critical hazard such as train collision or derailment may be possible because the RF-CBTC depends on the information through wireless communication. This paper discribes of performing Fall-Back system to detect train position in the case of rail break or communication failure to avoid train accident and allows train to be operated safely. It can be implemented with ATP function through track circuits using active-type transformers and axle counters, and allows train to be operated manually in emergency status.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.2
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• pp.133-142
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• 1993

In a computer-controlling wave generating system. it is sometimes necessary to incorporate the discrete transfer operation of wave board into control circuit in order to control the system in a more delicate way. A numerical filter simulating the transfer operation of wave board in time domain is designed in the form of a discrete recursive filter. The filter was applied to some example board inputs f3r either regular or irregular wave conditions in order to evaluate the filter performance. The filter outputs were compared with the results of theoretical analysis or the discrete convolution method. showing their excellent agreements. The discrete realization of the filter presented hen is in fact of the bilinear transformation. It was shown that the transformation always avoids the aliasing errors, being surely applicable with a sufficient accuracy even for the band-unlimited transfer function of wave board.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.6
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• pp.626-631
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• 1997

This paper represents the design of a real-time image preprocessing system. The preprocessing system performs hardware-wise mask operations and thresholding operations at the speed of camera output single rate. The preprocessing system consists of the preprocessing board and the main processing board. The preprocessing board includes preprocessing unit that includes a $5\times5$ mask processor and LUT, and can perform mask and threshold operations in real-time. To achieve high-resolution image input data($20485\timesn$), the preprocessing board has a linescan camera interface. The main processing board includes the image processor unit and main processor unit. The image processor unit is equipped with TI's TMS320C32 DSP and can perform image processing algorithms at high speed. The main processor unit controls the operation of total system. The proposed system is faster than the conventional CPU based system.

• Korean Journal of Applied Biomechanics
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• v.13 no.3
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• pp.99-116
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• 2003

The purpose of this study was to kinematics factors on during round-off at end of beam-salto backward stretched with step-out to cross on balance beam. Four elite female gymnastics players participated as subject of this study. The methods of this study was analyzed using three dimentional analysis. The results and conclusion of this paper is obtained as follows ; 1. The phase of time was the most short time in board touch down phase and board take-off phase. Also, it was shown a more long time in total time compared to previous study. 2. The horizontal displacement of each phase was shown the most high levels in balance beam landing. The vertical displacement was display a non-linearity increase in board take-of phase, and it was shown the most high levels in vertical displacement during landing of balance beam. 3. The horizontal velocity of each phase was shown the most high levels in board touch down, and it was display a gradually decreased levels because flight during board take-of. The resultant velocity of CG on each phase was shown the most high levels in board touch down and board take-off. 4. The angle of hip joint was shown the most high levels as performed a motion in extension state during board take-off, and the angle of knee joint was display a increased levels because of flight cause body extension in board take-off. Also the angle of ankle joint was shown a increasing levels during board take-off. Considering to this results, it is suggest that the change of kinematics factors in board touch down and board take-off is key role on the effective board control.

• Journal of the Korean Wood Science and Technology
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• v.18 no.4
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• pp.86-101
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• 1990

The primary objective of this research was to investigate the strength properties of Comply, a composite panel. fabricated with particle board as core material and veneer or plywood as face and back. 20types of comply composites were manufactured according to the four specific gravity levels(0.5, 0.6, 0.7 or 0.8) of particleboard core and three veneer or two plywood thicknesses for face and back. They were tested and compared with matching particleboard (control) on moisture content. specific gravity, bending properties(MOE, MOR SPL). nail resistance and internal bond strength. The obtained results were summarized as follows: The increasing effect of modulus of elasticity was shown by the increase of face and back veneer or plywood thickness. The modulus of rupture and stress at proportional limit of the comply composites bonded with 3mm thick veneers or 3mm thick plywood face and back were higher than 2mm thick veneer or 2mm thick plywood as face and back. Both of modulus of rupture and stress at proportional limit on bending of Comply were higher than those of control board. Also the modulus of elasticity of Comply showed much higher than that of control board. The nail resistance of Comply, composed of plywood as face and back was higher than that of veneer. The nail resistance of control board was higher than that of Comply at Sp.Gr 0.7 and 0.8 core boards. Internal bond of Comply, composed of 1mm and 2mm thick veneer as face and back was higher than that of 3mm thick veneer. The increasing effect of modulus of elasticity was shown by the increase of shelling ratio in Comply composed of veneer and plywood as face and back. The modulus of rupture was increased by the increment of shellmg ratio in Compiy, composed of plywood as face and back. The modulus of elasticity and modulus of. rupture of comply were higher than those of particleboard(control) in effect of shelling ratio. Therefore it was concluded that the mechanical property values of Comply were clearly greater than those of particleboard(control).

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.3
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• pp.270-276
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• 2013

The educational process and result of onboard training should be evaluated according to the 1995 Amendments to the International Convention on Standards of Training, Certification and Watch-keeping for seafarers(STCW), 1978. In particular, the revised Convention requires that a trainee's seagoing service must be recorded in each cadet's Training Record Book approved by the maritime administration responsible for the issuance of certificates of competency. Trainees for certification under regulation III/1 of the STCW Convention are required to complete an approved on-board training programme. The purpose of this paper is to understand the compliance of the education for an approved on-board training programme. The questionnaire was distributed among 110 cadets being trained on board the training ship of the maritime college of the Mokpo National Maritime University. In this study, we conducted the questionnaire survey which is related to the on-board training programme such as marine engineering; controlling the operation of the ship and care for persons on board; electrical, electronic and control engineering; etc. The survey revealed that onboard training program was normally satisfactory, however, lack of practical training tools and time have accounted for most of the reasons for dissatisfaction. Therefore, it is our goal to enhance the satisfactory value of onboard training education by analyzing the reason of the dissatisfaction.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.12
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• pp.562-570
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• 2002

The Purpose of this paper is to design and manufacture an educational system in order to demonstrate the causes and effects of electromagnetic induction.'rho educational system described in this study is a "jumping ring apparatus". This system demonstrates the principle of electromagnetic induction, a force from AC sources, Lenz's law of repulsion and transformer. The educational system is composed of a jumping ring apparatus, a sensor array, encoder, A/D converter, D/A converter and nonlinear controller. The educational system is controlled by 586 PC using Turbo C program. The sensor array is composed of 20 optical sensors. The nonlinear controller consists of nonlinear control algorithm and control board included SCR, FET and phase controller. The A/D converter is used to show the height of ring position to analog for an education purpose. The control signal calculated from the nonlinear control of algorithm send control board through 8 bit D/A convertor. Experiment results are given to verify that Proposed nonlinear controller is useful in on line control of the educational system.al system.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1684-1688
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• 2003

In this paper, position and speed control algorithm of LSM (Linear Stepping Motor) using general-purpose PCI I/O board is discussed. The main purpose of this paper is to show that LSM controller can be established on the non real time operating system such as Microsoft Win2000 under the assumption that thread priority strategy is well designed. We can guarantee sampling interval less than 5msec based on the Pentium III microprocessor. Therefore this kind of LSM controller development environment makes shorten the prior research period needed to verify the validness of the proposed control strategy. We also introduce the tool of the real-time windows target system of matlab, which also makes shorten the prior research period. The main focus of this paper is on developing general purpose NT device driver which can drive the general purpose PCI board and applying it for implementing the hardware interface for 2- axis linear stepping motor control. From the experimental results show that the developed LSM controller guarantee 2 micrometer resolution in position control with 10cm/sec moving speed