• Proceedings of the KSRS Conference
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• v.1
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• pp.500-503
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• 2006

To adjust the discrepancy between Light Detection and Ranging (LIDAR) strips, previous researches generally have been conducted using conjugate features, which are called feature-based approaches. However, irrespective of the type of features used, the adjustment process relies upon the existence of suitable conjugate features within the overlapping area and the ability of employed methods to detect and extract the features. These limitations make the process complex and sometimes limit the applicability of developed methodologies because of a lack of suitable features in overlapping areas. To address these drawbacks, this paper presents a methodology using area-based algorithms. This approach is based on the scheme that discrepancies make complex the local height variations of LIDAR data whithin overlapping area. This scheme can be helpful to determine an appropriate transformation for adjustment in the way that minimizes the geographical complexity. During the process, the contour tree (CT) was used to represent the geological characteristics of LIDAR points in overlapping area and the Iterative Closest Points (ICP) algorithm was applied to automatically determine parameters of transformation. After transformation, discrepancies were measured again and the results were evaluated statistically. This research provides a robust methodology without restrictions involved in methods that employ conjugate features. Our method also makes the overall adjustment process generally applicable and automated.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.3
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• pp.45-53
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• 1998

Traction control systems(TCS) improve vehicle acceleration performance and stability, particularly on slippery roads through engine torque and/or brake torque control. This research mainly deals with the engine control algorithm based on adjustment of the engine throttle valve opening. Hardware-in-the-loop simulation(HWILS) is carried out where the actual hardware is used for the engine/automatic transmission and TCS controller, while various vehicle dynamics are simulated on real-time basis. Also, use of the dynamometer is made in order to implement the tractive force that a road applies to the tire. Although some restrictions are imposed mainly due to the capability of the synamometer, simplified HWILS results show that the slip control algorithm can improve the vehicle acceleration performance for low-friction roads.

• Proceedings of the KIEE Conference
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• 2003.11b
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• pp.287-290
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• 2003

Over the last few years computer based image processing has become more prominent in forensic science. The image quality from many CCTV systems is too poor for facial recognition. but there are other human characteristics which allow us to recognize individuals from a distance. one of these parameters is a human's height. In this paper, we propose useful height measurement method by auto Position, size adjustment which uses image superimposition and edge detection regardless of lens distortion and not uses conventional photogrammetry calibration methods.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.4
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• pp.194-201
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• 2004

Optical fibers are indispensable fer optical communication systems that transmit large volumes of data at high speed. But the aligning technology under the sub-micron accuracy is required for the precise axis adjustment and connection. For the purpose of precise alignment of the optical arrays, in this research, we have developed the 12-axis(with 8 automated axis and 4 manual axis) automatic optical fiber alignment system including the image processing-based searching system, the automatic loading system using the robot and the suction toot and the automatic UV bonding system. In order to obtain the sub-micron alignment accuracy, two 4-axis PC-based motion controllers and the two 50nm resolution 6-aixs micro-stage actuated by micro stepping motors are adopted. The fiber aligning procedure consists of two steps. Firstly, the optical wave guide and an input optical array are aligned by the 6-axis input micro-stage with the IR camera. The image processing technique is introduced to reduce primary manual aligning time and result in achieving the 50% decrease of aligning time. Secondly, the IR camera is replaced by the output micro-stage and a wave guide and two optical arrays are aligned simultaneously before the laser power intensity delivered to the optical powermeter reached the threshold value. When the aligning procedure is finished, the wave guide and arrays are W bonded. The automatic loading/unloading system is also introduced and the entire wave guide handing time is reduced significantly compared to the former commercial aligning system.

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.8
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• pp.941-947
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• 1999

As pressure transducers are employed in many fields such as production facilities, test facilities vehicles and industrial machinery, there is an increasing need for high precision measurement of pressure without any calibration or maintenance. In this paper, we discuss the development of a smart thin film pressure transducer which is highly suitable for a precise measurement of pressure. The smart functions include automatic zero tracking, automatic span adjustment, temperature compenstion, continuous self-diagnostics for faults (open strain gages, abnormal data, incorrect A/D conversion, and overpressure), data memory and multi-drop communication with PC

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.3
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• pp.472-477
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• 1987

In order to prevent the short-channel effects due to threshold voltage adjustment implantation in conventional n+ doped silicon gate process, a new approach involving automatic doping of polycide by boron during source and drain implantation is introduced. P-MOSFET devece fabricated by theis approach shows improved short channel characteristics than conventional device with n+ doped gate. Some concerns of adopting this approach in CMOS technology are addressed togetheer with some suggestions.

• Proceedings of the Safety Management and Science Conference
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• 2000.11a
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• pp.203-216
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• 2000

In this paper, we Investigate rationales for feedback adjustment using some techniques associated with automatic process control based on some nonstatioary disturbance models. Feedback-control schemes are often operated so that the nature of the disturbance that is being compensated is concealed and unusual deviations from the target cannot be taken account of. In this connection feedback control schemes is useful to extend the idea of common causes and special causes to such systems. Minimum-cost feedback schemes are discussed for some simple ,but practically interesting ,models.

• Journal of Korean Society on Water Environment
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• v.36 no.5
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• pp.423-430
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• 2020

To improve the low treatment efficiency of sewage treatment plants, the separated sewer system must be maintained to provide an adequate flow rate and quality of the sewage under the effect of inflow. In this study, data from five locations of Namsuk, Dukgok1, Dukgok2, Kanggu, and Opo were used to conservatively calculate the inflow water volume. The sewer flow and rainfall data were collected in 2017. The factors in the standard method used to calculate the inflow of the combined sewer pipes including "rainy days", "rainfall impact period", and "period for basal sewer" were defined as 3 mm/day, continuous rain for two days, and two weeks prior to the inflow generation, respectively. "Rainy days", "rainfall impact period", and "period for basal sewer" were conservatively adjusted to 5 mm/day, continuous rain for five days, and three weeks prior to the inflow generation, respectively. As a results of the adjustment, the linearity (r²) was improved except for in Dukgok1. This implies that the conservative adjustment made in this study could improve the management quality of sewer pipes. Also, the linear correlation coefficient (a_i) between inflow and rainfall showed a large difference between the target locations, which can be another monitoring factor affecting the quality of sewer pipes. To improve the correlation based on the individual characteristics of the locations in Korea, the automatic algorithm for the inflow calculation should be developed by innovative intellectual technologies for application to the entire national area.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.6
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• pp.475-483
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• 2015

This study examined the feasibility of using an automatic lens distortion correction (ALDC) camera as the payload for a photogrammetric unmanned aerial vehicle (UAV) system. First, lens distortion for the interior orientation (IO) parameters was estimated. Although previous studies have largely ignored decentering distortion, this study revealed that more than 50% of the distortion of the ALDC camera was caused by decentering distortion. Second, we compared the accuracy of bundle adjustment for camera calibration using three image types: raw imagery without the ALDC option; imagery corrected using lens profiles; and imagery with the ALDC option. The results of image triangulation, the digital terrain model (DTM), and the orthoimage using the IO parameters for the ALDC camera were similar to or slightly better than the results using self-calibration. These results confirm that the ALDC camera can be used in a photogrammetric UAV system using only self-calibration.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.9
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• pp.951-959
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• 2013

In order to improve the speed performance of the direct drive mechanical systems, a comprehensive analysis of the velocity ripples of blushless DC motors should be required. Every motor has a certain level of torque ripples when it generates power, and the generated torque ripple also makes the velocity ripples in the final output stage in speed control system. In this paper, a novel algorithm for reducing velocity ripples is proposed based on the modeling of torque ripples for BLDC motors. Various algorithms have been made for torque ripples, but usually they should be installed inside the amplifier logic, result in the difficulties of flexibility for various kinds of torque ripples. The proposed algorithm was developed for being ported in the controller not the amplifier, and it has the capability of the automatic compensation adjustment. The performance of the proposed algorithm was verified by effective simulations and experiments.