• Korean Journal of Remote Sensing
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• v.32 no.6
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• pp.647-656
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• 2016

Growth of UAV technology leads to expansion of UAV image applications. Many UAV image-based applications use a method called incremental bundle adjustment. However, incremental bundle adjustment produces large computation overhead because it attempts feature matching from all image pairs. For efficient feature matching process we have to confine matching only for overlapping pairs using exterior orientation parameters. When exterior orientation parameters are not available, we cannot determine overlapping pairs. We need another methods for feature matching candidate constitution. In this paper we compare matching candidate constitution methods without exterior orientation parameters, including partial feature matching, Bag-of-keypoints, image intensity method. We use the overlapping pair determination method based on exterior orientation parameter as reference. Experiment results showed the partial feature matching method in the one with best efficiency.

• Applied Microscopy
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• v.41 no.4
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• pp.223-228
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• 2011

White light scanning interferometry has been employed to analyze surface features of diverse specimens. Long established in the field of materials engineering, the technique provides quantitative three-dimensional data as well as qualitative morphological images. It uses white light that is split and reflected from a reference mirror and an object. Merged together, the light generates interference patterns representing topographical contours of the object surface. The amplitude of the z-axis data is differentiated by gray scale. The technique allows the rapid, noncontact, and wide-field measurements for morphometry of biological specimens including chondrocytes, tooth enamel, and plant leaves. Quantification of the dimension of surface structures such as width, length, and elevation angle could be achievable by white light scanning interferometry. The light reflection from plant leaves has been assumed to be sufficient for the technique. Without special specimen preparations like conductive metal coating, the technique can be increasingly used for quantitative three-dimensional surface measurements of biological specimens.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.1
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• pp.79-90
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• 2016

The study has purposed in evaluating experiences for achievable accuracy and precision of time series at 3-D coordinates. It has been estimated from the kinematic medium-range baseline processing of Continuously Operating Reference Stations (CORS) for the potential application of crustal displacement analysis during an earthquake event. To derive the absolute coordinates of local CORS, it is highly recommended to include some of oversea country references, since it should be compromised of an observation network of the medium-range baselines within the length range from tens of kilometers to about 1,000 kilometers. A data processing procedure has reflected the dynamics of target stations as the parameter estimation stages, which have been applied to a series of experimental analysis in this research at the end. From the analysis of results, we could be concluded in that the subcentimeters-level of positioning accuracy and precision can be achievable. Furthermore, the paper summarizes impacts of satellite ephemeris, data lengths and levels of initial coordinate constraint into the positioning performance.

• Aerospace Engineering and Technology
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• v.10 no.1
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• pp.79-88
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• 2011

A fill-drain valve is operated by provided control gas at the ground for liquid propellant feeding system of space launch vehicle, which fills or drains on-board propellant tanks with a cryogenic oxidizer. We have analyzed and modified the data of fill-drain valve designed by Yuzhnoye. The simulation model of fill-drain valve is designed by using the AMESim code to predict and evaluate the dynamic characteristics and pneumatic behavior of valve. In this study, we performed a dynamic characteristic simulation on design parameter. And we could predict opening/closing time and pressures, operating performances on design parameters. This study will serve as one of reference guides to enhance the developmental efficiency of fill-drain valves with the various operating requirements, which shall be used in the Koreanized Space Launch Vehicle.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.2
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• pp.55-64
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• 1990

This paper concerned about a study on the direct pole placement PID self-tuning controller design for DC servo motor control system. The method of a direct pole placement self-tuning PID control for a DC servo motor of Robot manipulator tracks a reference velocity in spite of the parameters uncertainties in nonminimum phase system. In this scheme, the parameters of classical controller are estimated by the recursive least square (RLS)identification algorithm, the pole placement method and diophantine equation. A series of simulation in which minimum phase system and nonminimum phase system are subjected to a pattern of system parameter changes is presented to show some of the features of the proposed control algorithm. The proposed control algorithm which shown are effective for the practical application, and experiments of DC servo motor speed control for Robot manipulator by a microcomputer IBM-PC/AT are performed and the results are well suited.

• Nuclear Engineering and Technology
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• v.27 no.1
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• pp.45-52
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• 1995

In influence of the vapor phase turbulent stress (i.e., the too-phase Reynolds stress) to the characteristics of two-phase system in a horizontal pipe has been theoretically investigated. The average two-fluid model has been constituted with closure relations for stratified flow in a horizontal pipe. A vapor phase turbulent stress model for the regular interface geometry has been included. It is found that the second order waves propagate in opposite direction with almost the same speed in the moving frame of reference of the liquid phase velocity. Using the well-posedness limit of the two-phase system, the dispersed-stratified How regime boundary has been modeled. Two-phase Froude number has been found to be a convenient parameter in quantifying the onset of slugging as a function of the global void fraction. The influence of the taper phase turbulent stress was found to stabilize the flow stratification.

• Journal of Korea Society of Industrial Information Systems
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• v.21 no.1
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• pp.83-92
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• 2016

This paper is intended for small businesses, and small-scale empirical analysis of the peripheral region has a research model of the relationship between consulting factors that are studied in various aspects of the existing and business performance. In other words, a model that is presented in the study with reference to the existing verification as to whether any association exists between management consulting factors and business performance targets in wonju region auto parts production enterprises. Consulting factors were modeled separately by the consumer and supplier factors as business performance and financial performance were divided into non-financial performance, we designed the model parameters as set by the corporate culture. Research consulting consumer factors and supplier factors business performance (financial and non-financial) showed that having a significant impact on corporate culture, set as a parameter also having a positive effect on business performance It showed that.

• Journal of Biomedical Engineering Research
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• v.25 no.1
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• pp.77-82
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• 2004

The purpose of this study is to establish a reference for image acquisition for completion of a standard brain for diverse Korean population, and to develop a management system that saves and manage database of the acquired brain image and personal information of those who were tested. 3D MP-RAGE technique, which has excellent SNR and CNR and reduces the times for image acquisition, was selected for anatomical Image acquisition, and parameter values were obtained for the optimal image acquisition. The database management system was devised to obtain not only anatomical image data but also subjects' basic demographic factors, medical history, handedness inventory state-trait anxiety inventory, A-type personality inventory, self-assessment depression inventory questionnaires of Sasang Constitution Mini-Mental State Examination, intelligence test, and personality test via a survey questionnaire and to save and manage the results of the tests. In addition, this system was designed to have functions of saving, inserting, deleting, searching, and Printing of image da a and personal information of subjects, and to have accessibility to them as well as automatic connection setup with ODBC. This newly developed system may have major contribution to the completion of a standard brain of diverse Korean population in that it can save and manage their image date and personal information.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.8
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• pp.758-765
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• 2015

This paper proposes an attitude control system to keep the balance for a two-wheeled mobile manipulator which consists of a mobile platform and a three D.O.F. manipulator. In the conventional control scheme, complicated dynamics of the manipulator need to be derived for balancing control of a mobile manipulator. The method proposed in this paper, however, three links are considered as one body of mass and the dynamics are derived easily by using an inverted pendulum model. One of the best advantage of a sliding mode controller is low sensitivity to plant parameter variations and disturbances, which eliminates the necessity of exact modeling to control the system. Therefore the sliding mode control algorithm has been adopted in this research for the attitude control of mobile platform along the pitch axis. The center of gravity for the whole mobile manipulator is changing depending on the motion of the manipulator. And the orientation variation of center of gravity is used as reference input for the sliding mode controller of the pitch axis to maintain the center of gravity in the middle of robot to keep the balance for the robot. To confirm the performance of controller, MATLAB Simulink has been used and the resulting algorithms are applied to a real robot to demonstrate the superiority of the proposed attitude control.

• Journal of Korean Biological Nursing Science
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• v.20 no.2
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• pp.67-75
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• 2018

Purpose: The aim of this study was to explore the prevalence of major chronic diseases related to daily oral water intake and to identify the physiological parameters related to dehydration in Korean elderly. Methods: The data were collected from the sixth Korea Health and Nutrition Examination Survey (KHANES), which was a nationwide and cross-sectional survey in 2015. We analyzed 1,392 participants using t-test and logistic regression. All participants were divided into the adequate water intake (AWI) group and the non-adequate water intake (NAWI) group based on the dietary reference intakes for Koreans. Results: There was a significant difference in the water intake between the AWI (6.8 cups in a day) and NAWI (2.8 cups) groups (p< .001). There was no statistically significant association between the level of water intake and any of the major chronic diseases. Blood urea nitrogen (BUN) and BUN/Creatinine (Cr) ratio were significantly higher in the NAWI group. Especially, BUN/Cr ratio shows that the NAWI group reached dehydration status. Older age (adjusted odd ratio, OR= 1.07, 95% confidence interval, CI [1.04-1.10]), female gender (adjusted OR= 1.56, 95% CI [1.05-2.33]), lower body mass index (BMI) (adjusted OR = 1.00, 95% CI [0.92-1.00]), higher BUN (adjusted OR = 1.04, 95% CI [1.01-1.08]), and higher urine specific gravity (USG) (adjusted OR= 1.56, 95% CI [1.19-2.05]) were factors associated with the NAWI group. Conclusion: The findings suggest that the level of water intake needs to be considered in relation to age, gender, BMI, BUN, and USG. These are sensitive physiological parameters used for predicting dehydration of the elderly according to their daily oral water intake. It would be helpful to develop strategies to prevent dehydration in elderly individuals and enhance their water intake.