• Water for future
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• v.19 no.4
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• pp.339-346
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• 1986

A real-time single reservoir operation model using the Min-max Dynamic Programming for the flood control of Soyanggang Dam and Choongju Dam is developed. The objective function is to minimize the maximum release from each dam and the constraints are those from ther reservoir and channel characteristics. Control and utilization efficiencies are used to measure the performance of the reservoir operation method (ROM). In comparison with those of simulation models(such as the Rigid ROM, the Technical ROM and the Linear Decision Rule), the efficiencies of the optimization model are superior for all return periods.

• East Asian mathematical journal
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• v.40 no.2
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• pp.127-148
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• 2024

Maximum and minimum have a historical background in mathematics and occupy an important part of the differential unit in school mathematics. As the curriculum is revised, there are changes and problems in the way definition introduced. Therefore, this study analyzes the changes in the method of introducing maximum and minimum definitions following the reorganization of the 2007 and 2009 revised mathematics curriculum, and analyzes the differences in maximum and minimum definition methods compared to the nine mathematics II textbooks in the 2015 revised mathematics curriculum and three real analysis. In addition, methods to improve the terms used in relation to the maximum and minimum values are presented.

• Journal of Korea Multimedia Society
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• v.22 no.12
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• pp.1404-1414
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• 2019

Educational books commonly use some copyrighted images with various kinds of deformation for helping students understanding. When using several copyrighted images made by merging or editing distortion in legal, we need to pay a charge to original copyright holders for each image. In this paper, we propose an efficient matching algorithm by separating each copyrighted image with the merged and edited type including rotation, illumination change, and change of size. We use the Oriented FAST and Rotated BRIEF (ORB) method as a basic feature matching scheme. To improve the matching accuracy, we design a new MIN-MAX similarity in matching stage. With the distorted dataset, the proposed method shows up-to 97% of precision in experiments. Also, we demonstrate that the proposed similarity measure also outperforms compared to other measure which is commonly used.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.1
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• pp.253-262
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• 2016

This paper proposes a balance-swap method for the dynamic economic load dispatch problem. Based on the premise that all generators shall be operated at valve-points, the proposed algorithm initially sets the maximum generation power at $P_i{\leftarrow}P_i^{max}$. As for generator i with $_{max}c_i$, which is the maximum operating cost $c_i=\frac{F(P_i)-F(P_{iv_k})}{(P_i-P_{iv_k})}$ produced when the generation power of each generator is reduced to the valve-point $v_k$, the algorithm reduces i's generation power down to $P_{iv_k}$, the valve-point operating cost. When ${\Sigma}P_i-P_d$ > 0, it reduces the generation power of a generator with $_{max}c_i$ of $c_i=F(P_i)-F(P_i-1)$ to $P_i{\leftarrow}P_i-1$ so as to restore the equilibrium ${\Sigma}P_i=P_d$. The algorithm subsequently optimizes by employing an adult-step method in which power in the range of $_{min}\{_{max}(P_i-P_i^{min}),\;_{max}(P_i^{max}-P_i)\}$>${\alpha}{\geq}10$ is reduced by 10; a baby step method in which power in the range of 10>${\alpha}{\geq}1$ is reduced by 1; and a swap method for $_{max}[F(P_i)-F(P_i-{\alpha})]$>$_{min}[F(P_j+{\alpha})-F(P_j)]$, $i{\neq}j$ of $P_i=P_i{\pm}{\alpha}$, in which power is swapped to $P_i=P_i-{\alpha}$, $P_j=P_j+{\alpha}$. It finally executes minute swap process for ${\alpha}=\text{0.1, 0.01, 0.001, 0.0001}$. When applied to various experimental cases of the dynamic economic load dispatch problems, the proposed algorithm has proved to maximize economic benefits by significantly reducing the optimal operating cost of the extant Heuristic algorithm.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.11
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• pp.1428-1434
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• 2018

Canine cataract is developed with aging and can cause the blindness or surgical treatment if not treated timely. In this paper, we propose a method for extracting cataract suspicious areas automatically with FCM(Fuzzy C_Means) algorithm to overcome the weakness of previously attempted ART2 based method. The proposed method applies the fuzzy stretching technique and the Max-Min based average binarization technique to the dog eye images photographed by simple devices such as mobile phones. After applying the FCM algorithm in quantization, we apply the brightness average binarization method in the quantized region. The two binarization images - Max-Min basis and brightness average binarization - are ANDed, and small noises are removed to extract the final cataract suspicious areas. In the experiment with 45 dog eye images with canine cataract, the proposed method shows better performance in correct extraction rate than the ART2 based method.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.11a
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• pp.259-262
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• 2000

In this paper, an Adaptive neuro-fuzzy Inference system(ANFIS) using fuzzy min-max network(FMMN) is proposed. Fuzzy min-max network classifier that utilizes fuzzy sets as pattern classes is described. Each fuzzy set is an aggregation of fuzzy set hyperboxes. Here, the proposed method transforms the hyperboxes into gaussian menbership functions, where the transformed membership functions are inserted for generating fuzzy rules of ANFIS. Finally, we applied the proposed method to the classification problem of iris data and obtained a better performance than previous works.

• Tuberculosis and Respiratory Diseases
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• v.47 no.1
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• pp.26-34
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• 1999

Background : Generally $VO_2$ max is higher in treadmill exercise than cycle ergometer exercise. According to Hassen and Wasserman, $VO_2$ max with treadmill exercise is higher at ratio of 1.11 than that with cycle ergometer. $VO_2$ max also is influenced by race, sociocultural background, exercise habit In this study, $VO_2$ max and AT were evaluated between Treadmill and cycle exercise in male Korean college students. Method: Study subjects were 44 male college students. We randomized them into 2 groups; 24 students did treadmill exercise at first and 1 week later did cycle ergometer. Another 20 students did in opposite method. They made symptom limited maximal exercise. Author defined maximal exercise as followings: 1) respiratory exchange ratio(RER)> 1.1, 2) plateau>30 sec, 3) heart rate reserve(HRR) <15%, or 4) breathing reserve (BR)<30%. Otherwise their results are excluded as submaximal exercise. Anaerobic threshold(AT) was estimated by V-slope method. Results: $VO_2$ max and AT was $45.1{\pm}6.66m\ell$/kg/min and $26.0{\pm}6.78m\ell$/kg/min in treadmill and $34.9{\pm}5.89m\ell$/kg/min, $19.5{\pm}4.77m\ell$/kg/min in Cycle Ergometer. The measured-$VO_2max$/pred-$VO_2max$ was $98.8{\pm}13.24%$ in treadmill; $84.4{\pm}13.42%$ in cycle ergometer. Comparing $VO_2$ max in treadmill with that obtained by Hassen's method, there were significant differences.(p<0.01). At maximal exercise there were differences in HRR, $O_2$/pulse, BR, $V_E$/MVV, $V_E/VCO_2$ between treadmill and cycle but not in $V_E/VO_2$, Vd/Vt, Ti/Ttot. At AT there were differences in $O_2$/pulse, BR, $V_E$/MVV, Ti/Ttot between treadmill and cycle, otherwise not. Conclusion: According to the result of this study, there are larger gap between treadmill and cycle ergometer in normal Korean adults than foreign data, and it needs further study to obtain reference value of Korea.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.2C
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• pp.117-122
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• 2006

In this paper, we present a simple and general soft bit decision expression for a Gray coded PAM signal over additive white Gaussian noise(AWGN) channel with the log likelihood ratio(LLR). In order to reduce the complexity of the LLR calculation, we make the bitwise LLR expression simple by replacing the mathematical max functions of the conventional Max-Log-MAP expression with simple arithmetic functions associated with some deterministic parameters, such as a received value and distance between symbols on a signal space. Taking the implementation issues, like the area of silicon, the power consumption, the timing latency, and so on, into consideration, we submit that the proposed method is a promising alternative way to conventional methods for reconfigurable systems.

• Tuberculosis and Respiratory Diseases
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• v.42 no.6
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• pp.900-912
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• 1995

Background: Although graded exercise stress tests are widely used for the evaluation of cardiorespiratory performance, normal standards on respiratory gas exchange and ventilatory functions at maximal exercise in Koreans have not been well established. The purpose of this study is to provide reference values on these by sex and age, along with derivation of some of their prediction equations. Method: Symptom-limited maximal exercise test was carried out by Bruce protocol in 1,000 healthy adults consisting of 603 males and 397 females, aged 20~66 years. Among them VC, $FEV_1$ and MVV were also determined in 885 cases. All the subjects were members of a health center, excluding athletes. During the exercise, subjects were allowed to hold on to front hand rail of the treadmill for safety purpose. Results: The $VO_2\;max/m^2$, $VCO_2\;max/m^2$ and $V_E\;max/m^2$ were greater in males than in females and decreased with age. The RR max in men and women was similar but decreased slightly with age. The $V_T$ max was markedly greater in men but showed no significant changes with age in either gender. The mean of $V_T$ max/VC, $V_E$ max/MVV and BR revealed that there were considerable ventilatory reserves at maximal exercise even in older females. The regression equations of the cardinal parameters obtained using exercise time(ET, min), age(A, yr), height(Ht, cm), weight(W, kg), sex(S, 0=male; 1=female), VC(L), $FEV_1$(L) and $V_E$ max(L) as variables are as follows: $VO_2\;max/m^2$(L/min)=1.449+0.073 ET-0.007A+0.010W-0.006Ht-0.209S, $VCO_2\;max/m^2$(L/min)=1.672+0.063ET-0.008A+0.010W-0.005Ht-0.319S, VE max/$m^2$(L/min)=58.161+1.503ET-0.315A-9.871S or VE max/$m^2$(L/min)=47.873+6.548 $FEV_1$-5.715 S, and VT max(L)=1.497+0.223VC-0.493S. Conclusion: Respiratory gas exchange and ventilatory variables at maximal exercise were studied in 1,000 non-athletes by Bruce protocol. During exercise, the subjects were allowed to hold on to hand rail of the treadmill for safety purpose. We feel that our results would provide ideal target values for patients and healthy individuals to be achieved, since our study subjects were members of a health center whose physical fitness levels were presumably higher than ordinary population.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.4
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• pp.375-383
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• 2012

Together with the GPS-based approach, geolocation through mobile communication networks is a key technology for location-based service. Since the Mobile WiMAX system is considered as a candidate for fourth-generation mobile systems, it is important to investigate its location capability. The geolocation of Mobile WiMAX can be realized when the preamble symbols in the down-link channel are appropriately used for a TDOA (Time-Difference-of-Arrival) approach. However, the cellular structure of Mobile WiMAX inevitably generates co-channel interference, and it is difficult for the mobile terminal to acquire distance measurements from multiple base stations. Therefore, for geolocation via multilateration using the Mobile WiMAX network, it is very important to increase hearability. This paper proposes a geolocation method for Mobile WiMAX which employs interference cancellation and preamble signal overlapping for the enhancement of hearability. A novel interference cancellation strategy for complex-valued Mobile WiMAX signals is presented which has an iterative structure. Simulation results show that the proposed geolocation method provides the user's position with an accuracy of less than 20 m through the Mobile WiMAX cellular network if there is no multi-path or NLOS (None-Line-of-Sight).