• The Journal of Korea Robotics Society
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• v.7 no.1
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• pp.9-19
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• 2012

This paper proposes a performance index for the multiple shape object handling of dual arm manipulator to determine whether a robot is good or not. When the dual-arm manipulator grasps a fixed object and is posed, the dual-arm manipulator should procure a space to freely control the manipulator. As a performance evaluation parameter, each joint torque from current sensor signal is utilized. From the current information, torque and energy for each joint are estimated. In this paper an performance index for an unstructured object is defined by an energy-cost function, and stability analysis for each motion is derived by the maximum force to the object. The maximum force to the object is computed by the inertia of object and acceleration information of end-effector. The acceleration data are derived by the double derivation of each encoder signal. Manipulability measure which implies how efficiently the dual-arm manipulator can move with the grasped object, can be represented by the intersection of the two manipulability ellipsoids for the left and right arms. Effectiveness of the proposed algorithm has been verified through the practical simulations and real experiments.

• Journal of Power System Engineering
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• v.11 no.3
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• pp.66-72
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• 2007

This study proposed new method to decide the reference model necessary for design PID controller. In generally, control design problems using the reference model have the following two factors. One factor is that numerical model of the controlled system can be obtained extremely, and the other is that specification for the closed-loop dynamic performance is pure moderate. Therefore, the control design procedure is essentially based on the partial reference model matching which offers a reasonable method to simplify the design and the controller configuration under the controlled system uncertainty. ITAE(Integral of time-multiplied absolute error) performance index and Kitamori method etc. which were used a reference model method had a limit to settling time and rising time of reference model that it arrived to steady state response according to the controlled system. On this study, if it only knew peak time of overshoot and settling time by measurement signal of the controlled system, it can be made the reference model easily. We proposed new method to improve performance index of the reference model superior to existing reference model index and illustrate the numerical simulation results to show the effectiveness of proposed control method design.

• Journal of Environmental Impact Assessment
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• v.8 no.3
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• pp.77-90
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• 1999

The degree of green naturality (DGN) has played a key role for maintaining the environmental quality from inappropriate developments, although the quality and effectiveness of the mapping of DGN has been under debate. In this study, spatial distribution of degree of green naturality was initially estimated from forest stand maps that were produced from the aerial photo interpretation and extensive field survey. Once the boundary of initial classes of DGN were defined, it were overlaid with normalized difference vegetation index (NDVI) data that were derived from the recently obtained Landsat Thematic Mapper data. NDVI was calculated for each pixel from the radiometrically corrected satellite image. There were no significant differences in mean values of vegetation index among the initial DGN classes. However, the satellite derived vegetation index was very effective to delineate the developed and damaged forest lands and to adjust the initial value of DGN according to the distribution of NDVI within each class.

• Earthquakes and Structures
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• v.14 no.2
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• pp.129-142
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• 2018

The current paper introduces a new approach for development of damage index to obtain the maximum damage in the reinforced concrete frames caused by as-recorded single and consecutive earthquakes. To do so, two sets of strong ground motions are selected based on maximum and approximately maximum peak ground acceleration (PGA) from "PEER" and "USGS" centers. Consecutive earthquakes in the first and second groups, not only occurred in similar directions and same stations, but also their real time gaps between successive shocks are less than 10 minutes and 10 days, respectively. In the following, a suite of six concrete moment resisting frames, including 3, 5, 7, 10, 12 and 15 stories, are designed in OpenSees software and analyzed for more than 850 times under two groups of as-recorded strong ground motion records with/without seismic sequences phenomena. The idealized multilayer artificial neural networks, with the least value of Mean Square Error (MSE) and maximum value of regression (R) between outputs and targets were then employed to generate the empirical charts and several correction equations for design utilization. To investigate the effectiveness of the proposed damage index, calibration of the new approach to existing real data (the result of Park-Ang damage index 1985), were conducted. The obtained results show good precision of the developed ANNs-based model in predicting the maximum damage of regular reinforced concrete frames.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.136-145
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• 2004

In companion paper, the composition and structure of the traffic environment is derived. Rules to regulate agent behaviors and the frameworks to communicate between the agents are proposed. In this paper, the model of a driver agent which controls a vehicle agent is constructed. The driver agent is capable of having different driving styles. That is, each driver agent has individual behavior settings of the yielding index and the passing index. The yielding index can be defined as how often the agent yields in case of lane changes, and the passing index can be defined as how often the agent passes ahead. According to these indices, the agents overtake or make their lanes for other vehicles. Similarly, the vehicle agents can have various vehicle dynamic models. According to their dynamic characteristics, the vehicle agent shows its own behavior. The vehicle model of the vehicle agent contains the nonlinear subcomponents of engine, torque converter, automatic transmission, and wheels. The simulation has proceeded for an interrupted flow model. The result has shown that it is possible to express the characteristics of each vehicle and its driver in a traffic flow, and that the change of the traffic state is closely related with the distance and the signal delay between intersections. The system developed in this paper shows the effectiveness and the practical usefulness of the traffic simulation.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.6
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• pp.768-775
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• 2014

The purpose of this study was to analyze consumption patterns of health functional foods (HFF) according to climacteric symptoms. Subjects were 450 middle-aged women divided into four groups by Kupperman's index. This study collected all information by self-administrated questionnaires. Higher Kupperman's index was associated with higher Menopause-specific quality of life questionnaire (MENQOL) (P<0.001) and current smoker ratio (P<0.01) as well as lower monthly income (P<0.05). Exactly 28.4% of subjects showed negative responses to effectiveness of HFF. The average number of HFF intake per person was 2.01. The main reason for consumption of HFF was treatment or prevention of disease (33.6%). The information source for buying HFF was family or relatives (40.0%). The main types of HFF were vitamins (28.2%), omega-3 fatty acid (18.6%) and red ginseng (17.3%). The intake ratio of individual approval type (Cynanchum extract and Angeli extract) was significantly higher in subjects with high Kupperman's index (P<0.001). In conclusion, these results can be used as basic data that reflect middle-aged women's needs for HFF intake according to climacteric symptoms.

• Journal of Periodontal and Implant Science
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• v.35 no.4
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• pp.975-989
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• 2005

Periodontal disease is caused by accumulation of bacterial plaque. For the reason, plaque control is essential to control and prevent periodontal disease. Among the plaque control methods, mechanical plaque removal, tooth brushing is common and reliable. But it depends on individual habituation and their manner. To catch up the gap of effectiveness, lots of oral hygiene appliances have been developing. Powered toothbrush is the most interesting field and is showing on the market with various motion type. This study was performed to compare clinical effects of plaque removal between powered toothbrush and manual toothbrush. The results were as follows : 1. Plaque index was decreased statistically after the brushing than before the brushing in every group.(p<0.05) 2. Comparing plaque index among the three groups before and after brushing, there were no statistically significant differences. 3. Interproximal plaque index was decreased statistically after the brushing than before the brushing in every group.(p<0.05) 4. Comparing interproximal plaque index among the three groups before and after brushing, there were no statistically significant differences.

• Journal of the Korean Institute of Telematics and Electronics
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• v.10 no.1
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• pp.1-8
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• 1973

It is often difficult, or almost impossible, in most cases to obtain the optimal solution to the non-linear control systems by analytical method. In this paper, the authors have treated with the technique of parameteric adaptation which is introduced into the performance index, in order to circumvent the difficulties arising in seal.ch of optimal policy for the non-linear feedback control systems. This approach is shown to provide the advantage of making it possible to design the non-linear feedback control system even if the design specifications are not completely discribed in mathematical form. This is fundamentally due to a certain degree of freedoln in design, which this method allows the designer in establishing the performance index. The effectiveness and feasibilities of this concept are demonstrated by working out some illustrative examples with the performance index of integral quadratic form.

• Korean Journal of Organic Agriculture
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• v.30 no.4
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• pp.499-516
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• 2022

Blueberry producers' management is failing as a result of the price decline caused by an increase in blueberry imports and the accompanying deterioration in management. Consequently, an endeavor was undertaken to verify the measurement and impact from the standpoint of efficiency and productivity of blueberry management, and to offer an indication of management improvement through analysis. Using the Rural Development Administration's income survey data, the data for twenty-four blueberry farms was analyzed. First, the management effectiveness of blueberry cultivators was evaluated. Using the CCR model (0.7297) and the BCC model (08148), the efficiency of a farm was examined. When the efficiency is one, CCR is ten and BCC is fifteen, and in overall, it was found to be ineffective, the efficiency declined from 2018 to 2019, but climbed again in 2020, according to the annual analysis. The MPI index was then used to examine productivity. T2's MPI index was 1.3338, whereas T3's MPI index was 0.8896, demonstrating a considerable decline in TC. This indicates that technological progress is not being accomplished, necessitating the need for countermeasures. In order to improve the management efficiency of blueberry producers, it is necessary to reduce costs and improve receivable prices through producer organization, and to actively introduce new technologies.

• International Journal of Highway Engineering
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• v.18 no.3
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• pp.95-107
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• 2016

PURPOSES : This study compared two measures of traffic flow effectiveness on roads with roundabouts and signalized intersections and determined the more appropriate measure. METHODS : In addition to average delay time, the conventionally used measure, average travel time was introduced to measure traffic flow effectiveness because it is able to be obtained through field survey and reflect different travel distances and speed limits of roundabouts and signalized intersections. Using the two measures, roundabouts and signalized intersections were compared through simulations in terms of traffic flow effectiveness. RESULTS : For one-way single-lane roads, the two measures indicated consistent results that roundabouts were more effective than were signalized intersections when the traffic volume was less than 300 vphpl but vice versa when it exceeded 450 vphpl; however, the measures yielded inconsistent results when the volume was 350~400 vphpl. For one-way double-lane roads, the two measures indicated consistent results that roundabouts were more effective than were signalized intersections when the volume was less than 200 vphpl but vice versa when it exceeded 400 vphpl; however, the measures yielded inconsistent results when the volume was 250~350 vphpl. The results obtained using the two measures differed substantially for double-lane roads because behaviors such as weaving and lane changing at roundabouts are more common in double-lane roads than in single-lane roads. CONCLUSIONS : The average delay time would be lower on roads with roundabouts, but average travel time would be lower on roads with signalized intersections. Thus, evaluating the relative effectiveness of roads with roundabouts and signalized intersections by using average delay time alone would be inappropriate, whereas using average travel time as the evaluation index would yield fairer results.