• Journal of Bio-Environment Control
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• v.33 no.3
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• pp.129-138
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• 2024

This study was conducted to determine the differences in bioactive compounds and antioxidant activity according to the ripening stage of tomato fruits with different skin colors. The tomato samples used three tomato cultivars distinguished by their skin colors as yellow, black, and red at the mature stage. Tomato samples were analyzed for soluble sugars, lycopene, ascorbic acid, polyphenols, and antioxidant activity after being harvested at green, breaker, turning, and mature. The major sugars in tomato fruits are fructose and glucose. The content of fructose and glucose in yellow tomatoes gradually increased during the ripening stages. However, red and black tomatoes, their levels exhibited an initial increase at the breaker points, followed by a period of relative constancy. The lycopene contents in fruits of all skin colors showed a significant increase during ripening stages. The highest content of lycopene was observed at the mature stage in red tomato fruits. Differential patterns in the accumulation of ascorbic acid between yellow and black or red tomato fruits were detected during the entire ripening stages. In yellow tomato fruit, the content of ascorbic acid remained consistently low throughout the ripening stages. Ascorbic acid content in black tomato fruits significantly increased to 2,249 mg·kg^-1 of tomato fruits at the mature stage, while in red tomato fruits, it gradually increased to 3,529 mg·kg^-1 of fruits at the mature stage. Quercitrin content in tomato fruits gradually decreased during the ripening stages. In yellow tomato fruits, the ABTS radical scavenging activity abruptly increased at the turning stages, while in black and red tomato fruits, it gradually increased according to the ripening stages. The DPPH radical scavenging activity in tomato fruits significantly increased at the turning stages.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.494-496
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• 2002

A bi-directional and multi-channel wireless telemetry capsule, 11mm in diameter, is presented that can transmit video images from inside the human body and receive a control signal from an external control unit. The proposed telemetry capsule includes transmitting and receiving antennas, a demodulator, decoder, four LEDs, and CMOS image sensor, along with their driving circuits. The receiver demodulates the received signal radiated from the external control unit. Next, the decoder receives the stream of control signals and interprets five of the binary digits as an address code. Thereafter, the remaining signal is interpreted as four bits of binary data. Consequently, the proposed telemetry module can demodulate external signals so as to control the behavior of the camera and four LEDs during the transmission of video images. The proposed telemetry capsule can simultaneously transmit a video signal and receive a control signal determining the behavior of the capsule itself. As a result, the total power consumption of the telemetry capsule can be reduced by turning off the camera power during dead time and separately controlling the LEDs for proper illumination of the intestine.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.6
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• pp.1-7
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• 2011

This paper presents implementation and control of a two wheeled mobile robot system which consists of two systems, an inverted pendulum system and a mobile robot system. Control purpose is to regulate its balancing and navigation. The balancing robot has advantages of one point turning and robust balancing against disturbances from the ground. Simulation studies of local and global control methods are performed. Since the robot is implemented to have a symmetrical structure, simple linear control algorithms are used for balancing and navigation. Low cost sensors such as gyro and tilt sensor are fused together to detect the inclined angle. Experimental studies of following desired circular trajectory are conducted.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.9
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• pp.896-902
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• 2007

This paper proposes a vision-based kinematic control method for mobile robots with camera-on-board. In the previous literature on the control of mobile robots using camera vision information, the forward velocity is set to be a constant, and only the rotational velocity of the robot is controlled. More efficient motion, however, is needed by controlling the forward velocity, depending on the position in the corridor. Thus, both forward and rotational velocities are controlled in the proposed method such that the mobile robots can move faster when the comer of the corridor is far away, and it slows down as it approaches the dead end of the corridor. In this way, the smooth turning motion along the corridor is possible. To this end, visual information using the camera is used to obtain the perspective lines and the distance from the current robot position to the dead end. Then, the vanishing point and the pseudo desired position are obtained, and the forward and rotational velocities are controlled by the LOS(Line Of Sight) guidance law. Both numerical and experimental results are included to demonstrate the validity of the proposed method.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.1
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• pp.149-153
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• 2003

This study was conducted to survey the utilization possibility of composting system of small scale static pile with animal manure produced from cattle shed and the effect of addition of microorganism on the maturity of compost. Microorganisms added in composting substrate were bacteria+lactobacillus(BL)+photo.(BLP). The composting practiced was a windrow system without aeration equipment and turning was practiced periodically. The water content of substrate mixed with cow manure, rice husk, and sawdust was about 60%. The temperature during the composting process was increased at over $60^{\circ}C$ within 3 days after composting starting. Increase of temperature at the early stage of composting was fasten in BLP and BL than Control. Because the pH of the raw material was high, the changes of pH during composting was little and stabilized in weak alkaline condition. EC value was high for accumulation of manure and urine excreted continuously by animal and the changes of those during composting occurred in 5~10% increase. Reduction rates of C/N ratio were the largest as the 22.7% in BLP and 19.2and 17.5% in BL and Control respectively. In the evaluation of phytotoxicity, there was stabilized within the short time in BLP and not the difference between BL and Control. Treatment of animal manure produced from small scale cattle shed was possible by using the small scale static pile composting system with reasonable water content and turning and the addition of microorganism in composting substrate was effected on the temperature increase at the early stage of composting and reduction of plant toxicity compounds but little on the maturity of compost.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.65-71
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• 2012

This paper is concerned with the suppression of brake system noise and vibrations of the elevator traction machine by means of a solenoid control technique. The solenoid is used to hold the brake shoe, which is then released by turning the solenoid off. Since the brake shoe hits the brake disk, vibrations and noise occur. We develop the solenoid control technique based on the dynamic behavior of the solenoid. The theoretical model for the solenoid is modeled by using linear magnetic principles. The solenoid model was then combined with the vibration model to simulate the brake system vibrations. The simulation results show that the additional pulse input to the solenoid can decrease the vibrations. The timing of the applied pulse is determined by observing the current. The experimental results show that both the vibrations and noise can be substantially decreased, which validates the approach developed in this paper.

• Journal of Drive and Control
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• v.14 no.3
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• pp.8-17
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• 2017

With automobiles sharply increasing in numbers worldwide, we are faced with critical social issues such as traffic accidents, traffic jams, environmental pollution, and economic inefficiency. In response, research on ITS is promoted mainly by regions with advanced automotive industry such as the U.S., Europe, and Japan. While Korea is working on moving forward in the global market through developing and turning to global standards systems related to ASV (Advanced Safety Vehicle), the country is not fully prepared for such projects. The purpose of ACC (Adaptive Cruise Control) is to control a vehicle's longitudinal speed and distance and minimize driver workload. Such a system should be valuable in preventing accidents, as it reduces driver workload in the 21st-century world of telematics created by development of the automobile culture industry. In this light, the thesis presents a method to test and evaluate ACC system and a mathematical method to assess distance. For the proposed test and evaluation, theoretical values are tested with vehicle test and a database is acquired, by using vehicles equipped with an ACC system. Theoretical evaluation criteria for developing ACC system may be used and scenario-specific evaluation methods may find useful application through testing the formula proposed by comparing the database and mathematical method.

• IEMEK Journal of Embedded Systems and Applications
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• v.17 no.5
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• pp.257-263
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• 2022

Active stabilizers use signals such as steering angle, yaw rate, and lateral acceleration to vary the roll stiffness of the front and rear suspension depending on the vehicle's driving conditions, and are attracting attention as RSC (Roll Stability Control) system that suppresses roll when turning and improves ride comfort when going straight. Various studies have been conducted in relation to active stabilizer bars and RSC systems. However, accurate modeling of passive stabilizer model and active stabilizer model and vehicle dynamics analysis result verification are insufficient, and performance result analysis related to vehicle roll angle estimation and electric motor control is insufficient. Therefore, in this study, an accurate vehicle dynamics model was constructed by measuring the passive/active stabilizer bar model and component parameters. Based on this, the analysis result with high reliability was derived by comparing the roll angle estimation algorithm based on the lateral acceleration and suspension of the vehicle with the actual vehicle driving test result. In addition, it was intended to accurately analyze the motor torque characteristics and roll reduction effects of the electric motor-driven RSC system.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.2
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• pp.124-132
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• 2023

In this paper, we present a simple classification model based on statistical features and demonstrate the successful implementation of a brain-computer interface (BCI) based light on/off control system. This research shows study and development of light on/off control system based on BCI technology, which allows the users to control switching a lamp using electroencephalogram (EEG) signals. The logistic regression algorithm is used for classification of the EEG signal to convert it into light on, light off control commands. Training data were collected using 14-channel BCI system which records the brain signals of participants watching a screen with flickering lights and saves the data into .csv file for future analysis. After extracting a number of features from the data and performing classification using logistic regression, we created commands to switch on a physical lamp and tested it in a real environment. Logistic regression allowed us to quite accurately classify the EEG signals based on the user's mental state and we were able to classify the EEG signals with 82.5% accuracy, producing reliable commands for turning on and off the light.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1669-1674
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• 2004

In this paper, a nonlinear information filter (IF) for curvilinear motions in an interacting multiple model (IMM) algorithm to track a maneuvering vehicle on a road is investigated. Driving patterns of vehicles on a road are modeled as stochastic hybrid systems. In order to track the maneuvering vehicles, two kinematic models are derived: A constant velocity model for linear motions and a constant-speed turn model for curvilinear motions. For the constant-speed turn model, a nonlinear IF is used in place of the extended Kalman filter in nonlinear systems. The suggested algorithm reduces the root mean squares error for linear motions and rapidly detects possible turning motions.