• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.5
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• pp.593-597
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• 2004

This paper presents the new design method of fuzzy control system for nonlinear system. Many conventional design methods for fuzzy controller find the control gain for stabilizing fuzzy controller with some mathematical approaches. However, there exist some controllers which are hard to design with mathematical approach. In order to solve these problems, we propose the intelligent design method for fuzzy controller by using genetic algorithm with evolution strategy. The genetic algorithm with evolution strategy finds the control gain by changing the evolution region of chromosome. Finally, an application example of stabilizing a cart-pole typed inverted pendulum system will be given to show the stabilizability of the fuzzy controller.

• Journal of Radiation Protection and Research
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• v.3 no.1
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• pp.6-22
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• 1978

High energy electron beams took effect for tumor radio-therapy, however, had a lot of problems in clinical application because of various conversion factors and complication of physical reactions. Therefor, we had experimentally studied the important properties of high energy electron beams from the linear accelerator, LMR-13, installed in Yonsei Cancer Center. The results of experimental studies on the problems in the 8, 10, 12 Mev electron beam therapy were reported as following. 1. On the measurements of the outputs and absorbed doses, the ionization type dosimeters that had calibrated by $^{90}Sr$ standard source were suitable as under 3% errors for high energy electrons to measure, but measuring doses in small field sizes and the regions of rapid fall off dose with ionization chambers were difficult. 2. The electron energy were measured precisely with energy spectrometer consisted of magnet analyzer and tele-control detector and the practical electron energy was calculated under 5% errors by maximum range of high energy electron beam in the water. 3. The correcting factors of perturbated dose distributions owing to radiation field, energy and material of the treatment cone were checked and described systematically and variation of dose distributions due to inhomogeneous tissues and sloping skin surfaces were completely compensated. 4. The electron beams, using the scatterers; ie., gold, tin, copper, lead, aluminium foils, were adequately diffused and minimizing the bremsstrahlung X-ray induced by the electron energy, irradiation field size and material of scatterers, respectively. 5. Inproving of the dose distribution from the methods of pendulum, slit, grid and focusing irradiations, the therapeutic capacity with limited electron energy could be extended.

• Women's Health Nursing
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• v.21 no.4
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• pp.297-307
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• 2015

Purpose: This study was aimed to understand the meaning and essentials of the experience of burnout for hospital nurses with turnover intention. Methods: The design was a qualitative research of phenomenological study. Participants: Seven hospital nurses who had worked over three years and had experiences of turnover intention in a hospital with over 400 beds were included. Results: Nine meaningful themes related to burnout experiences and four theme clusters of 1) battery warning sounds almost out; 2) the player who hit the drum and double-headed drum; 3) the target flying arrow without a break; and 4) the pendulum swaying to turn over. Registered nurses (RNs) felt burnout with an overload of work and by the thought that it was illegal action for registered nurses to receive insufficient rewards for their work. RNs also experienced there were no problem solving strategies to verbal violence by patient and medical team. Conclusion: The findings show that burnout experiences for those who had turnover intention was developed from the insight that insufficient training to do work independently with over-load for nurses was not ethical. It suggests that it is necessary to rethink training systems for nursing and hospitals to relieve turnover intention.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.2
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• pp.10-16
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• 2012

Currently, the majority of systems which are non-linear are in need of the correct system equations for controlling and monitoring. Therefore, the correct estimation of parameters is crucial. Generally, parameters are changed due to system deterioration or sudden environmental alterations. Given the limitations of system monitoring unstable controls can arise. In the following paper, the parameter estimation method is proposed using software filters to combat these system instabilities. For dynamic instances, a powerful particle filter is used to control the nonlinear and noisy environments in which they take place. Using a setup simulation comprised of a slider and pendulum, the state variable of noise is obtained. After collecting the data, the proposed algorithm is used to estimate both the state variable and its parameters. Finally, these results are checked with correct parameter estimations to evaluate and verify the algorithms performance.

• International Journal of Highway Engineering
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• v.19 no.1
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• pp.53-62
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• 2017

PURPOSES : This research was a fundamental study on the application of an integral $TiO_2$ solution to asphalt concrete pavement. The integral $TiO_2$ solution was produced in pilot production equipment; application of the integral $TiO_2$ solution to asphalt pavement was conducted to examine the pollution-reducing capability of photocatalytic compounds such as $TiO_2$. The photocatalytic $TiO_2$ reacted with air pollutants, converting them into small amounts of relatively benign molecules. METHODS : In this study, laboratory experiments were conducted using five various testing methods. Tensile strength ratio (TSR) and British pendulum test (BPT) were conducted in order to evaluate the properties of asphalt pavement subsequent to the integral $TiO_2$ solution coating. In addition, methylene blue testing, a measurement of nitrate on the coated pavement, and nitrogen oxide (NOx) reduction testing were conducted in order to evaluate photocatalytic reaction. Lastly, a UV-A lamp was used as a light source for photocatalytic reactions. RESULTS : Test results indicated no change in the properties of asphalt pavement following the integral $TiO_2$ solution coating. In order to evaluate the performance of asphalt pavement as a function of $TiO_2$, the moisture susceptibility and skid resistance were investigated. The moisture susceptibility and skid resistance satisfied there quirements related to pavement quality and safety specification. Furthermore, the effects of reduction of air pollution were significantly improved as determined via the methylene blue test and NOx reduction test. The $TiO_2$-paved asphalt specimen exhibited approximately 43% reduction of NOx. CONCLUSIONS : This study has suggested that applying $TiO_2$ rarely impacts asphalt pavement performance measures such as moisture susceptibility and skid resistance, and that its application may be a better means of reducing air pollution. Further studies, such as proper $TiO_2$ dosage rates and compatibility with various pavement types, are required to broaden and generalize its application.

• Journal of Korean Association for Spatial Structures
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• v.8 no.2
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• pp.73-84
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• 2008

The various systems as the seismic resistance systems are used to reduce the seismic response of structure. And the seismic isolation system among them is the system that reduces the seismic vibration to be transmitted from foundation to upper structure. The purpose of isolation system is to lengthen the period of structure and make its period shift from the dominant period of earthquake. In this study, the seismic behavior of arch structure with lead rubber bearing(LRB) and friction pendulum system(FPS) is analyzed. The arch structure is the simplest structure and has the basic dynamic characteristics among large spatial structures. Also, Large spatial structures have large vertical response by horizontal seismic vibration, unlike seismic behavior of normal rahmen structures. When horizontal seismic load is applied to the large spatial structure with isolation systems, the horizontal acceleration response of the large spatial structure is reduced and the vertical seismic response is remarkably reduced.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.3
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• pp.1-11
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• 2008

This paper proposes a real-time method using a 3-axis accelerometer to enhance blurred images taken from a camera loaded in mobile devices. Blurring phenomenon is a smoothing effect occurring in photo images. Algorithms to cope with blurring phenomenon is essential since small-size mobile devices tremble severely by even a tiny hand-shaking of a user. In this paper, accurate sensing characteristics of the 3-axis accelerometer is acquired by applying the sensor in pendulum motion and the blurring phenomenon is modeled as a uniform distribution and Gaussian distribution. Also, non-Gaussian distributed model is observed in the experiment of real blurring phenomenon and a particular deblurring function is designed by reversing the model. It has been demonstrated that the application of trembling information to the deblurring function adequately removes the blurring phenomenon.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.4
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• pp.499-505
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• 2011

In this paper, we proposed an adaptive fuzzy sliding mode control for nonlinear systems without parameter projection method. By modifying the controller structure, the parameters of the estimated input gain function are guaranteed not being identically zero and it is shown that the control scheme will not cause any implementation problem even if the estimated value of input gain function is zero at any moment during on-line operations. Except for the input gain function which an approximate estimate for its lower bound is needed, the proposed control scheme does not assume a priori the exact values of the bounding parameters. Based on Lyapunov synthesis methods, the overall control system guarantees that the tracking error asymptotically converges to zero and that all signals involved in controller are uniformly bounded. This can be illustrated by the simulation results for an inverted pendulum system.

• The Journal of Engineering Geology
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• v.8 no.3
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• pp.235-245
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• 1998

Adquate friction resistance is needed to prevent pavement slipperiness and to allow vehicles to stop in a reasonable distance. Performance of the aggregates is reduced over time by wear and polishing as a consequence of vehicular traffic. In this research, the objective was to develop a laboratory method to test Indiana gravel aggregates to predict field performance, and determine causes for the range of values amang gravel aggregates. The assessment of gravel sources was primarily on the basis of individual rock types and those proportions comprising the gravel. Polish and friction values were determined in the laboratory with the British Wheel and Pendulum. The gravels of this study were composed primarily of carbonate aggregates that showed considerable variability in polishing thresholds. Igneous and metamorphic constituents polished to a lesser degree and are expected to improve overall aggregate performance. Estimates of the IFV (Initial Friction Value) and PV (Polished Value) for crushed gravel samples can be made based on the percentage of rock types present in the sample. A weighted average is used to make this calculation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.4
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• pp.61-80
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• 2012

This study is to offer the basic data for restoration and conservation of wetland ecosystem by surveying and analysing the flora distributed in the Binae marsh, Namhan River, Chungju-si. The flora in the Binae marsh were verified 204 taxa including 48 families, 152 genera, 179 species, 23 varieties and 2 forms. In flora, pteridophyta were 2 taxa including 1 family, 1 genus and 2 species, among angiospermae, dicotyledonae were 153 taxa including 37 families, 110 genera, 138 species, 13 varieties and 2 forms and monocotyledonae were 49 taxa including 10 families, 41 genera, 39 species and 10 varieties. In the result of classifying the life form of flora, megaphanerophytes (M), nanophanerophytes (N) and chamaiphytes (Ch) were each 9 taxa (4.4%), 37 taxa (18.1%) of hemicryptophytes (H), 19 taxa (9.3%) of geophytes (G), 97 taxa (47.6%) of therophytes (Th) and 24 taxa (11.8%) of hydrophytes (HH). The rare plant designated by Korea Forest Service was 1 taxa (Aristolochia contorta), and the endemic plant was 1 taxa (Salix koriyanagi) too. The specific plants by floristic region were 6 taxa. From among these, the species of degree I were 5 taxa including Salix chaenomeloides, Aristolochia contorta, Artemisia selengensis, Cirsium pendulum and Vallisneria natans, and degree III was 1 taxa including Alisma orientale. The naturalized plants were 45 taxa and the invasive alien plants were 3 taxa including Sicyos angulatus, Ambrosia artemisiifolia and Ambrosia trifida. The naturalized index (NI) was about 22.1%, 16.1% of urbanized index (UI) and 27.3% of disturbed index (DI). The extinct species by construction were 17 taxa including Persicaria sagittata, Typha orientalis, Zizania latifolia and so forth. The new-occured species were 14 taxa including Brassica juncea, Thlaspi arvense, Carduus crispus and so forth. The important species among the extinct species were Aristolochia contorta, Alisma orientale and Vallisneria natans.