• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.152-153
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• 2006

The new approach to buffer layer design for CIGS solar cells that permitted to reduce the buffer absorption losses in the short wavelength range and to overcome the disadvantages inherent to Cd-free CIGS solar cells was proposed. A chemical bath deposition method has been used to produce a high duality buffer layer that comprises thin film of CdS and Zn-based film. The double layer was grown on either ITO or CIGS substrates and its morphological, structural and optical properties were characterized. The Zn-based film was described as the ternary compound $ZnS_x(OH)_y$. The composition of the $ZnS_x(OH)_y$ layer was not uniform throughout its thickness. $ZnS_x(OH)_y$/CdS/substrate region was a highly intermixed region with gradually changing composition. The short wavelength cut-off of double layer was shifted to shorter wavelength (400nm) compared to that (520 nm) for the standard CdS by optimization of the double buffer design. The results show the way to improve the light energy collection efficiency of the nearly cadmium-free CIGS-based solar cells.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.5
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• pp.593-598
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• 2005

The standard Kalman filter has been used to estimate the states of the target, but in the presence of a maneuver, its error is occurred and performance may be seriously degraded. To solve this problem, this paper presents a new intelligent tracking algorithm using the fuzzy Kalman filter. In this algorithm, the unknown acceleration is regarded as an additive process noise by using the fuzzy logic based on genetic algorithm(GA) method. And then, the modified filter is corrected by the new update equation method which is a fuzzy system using the relation between the filter residual and its variation. To shows the feasibility of the suggested method with only one filter, the computer simulations system are provided, this method is compared with multiple model method.

• Korean Journal of Optics and Photonics
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• v.22 no.3
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• pp.141-150
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• 2011

Although significant amount of research has been done to develop LED lamp packages for improved performance, no standard theories or guidelines have been established yet for designing LED lamp packages. In this paper, the photon extraction efficiency depending on both the InGaN/Sapphire LED chip structure and its attachment schemes for chip mounting has been analyzed by using the Monte Carlo photon simulation method. Based on the results of the analysis, we have derived guidelines for LED lamp package design, which can be utilized in industries or research institutes for designing new LED lamp packages optimized for particular applications.

• Korean Journal of Ichthyology
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• v.32 no.4
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• pp.245-250
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• 2020

Two specimens (407~438 mm in standard length) of a pleuronectid Atheresthes evermanni were collected by a gill-net from the coastal waters off Goseong-gun, middle East Sea of Korea. These specimens are characterized by a large mouth, narrow interorbital space, invisible eye at blind side, long and slender gill rakers, emarginated caudal fin, and almost straight lateral line. This is the first record of A. evermanni in Korean waters; we therefore add it to the Korean fish fauna and propose new Korean name, "Hwa-sal-chi-ga-ja-mi-sog" for the genus and "Hwa-sal-chi-ga-ja-mi" for the species, respectively.

• Steel and Composite Structures
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• v.30 no.3
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• pp.293-304
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• 2019

The optimum cost of a reinforced concrete plane and space frames have been found by using the Genetic Algorithm (GA) method. The design procedure is subjected to many constraints controlling the designed sections (beams and columns) based on the standard specifications of the American Concrete Institute ACI Code 2011. The design variables have contained the dimensions of designed sections, reinforced steel and topology through the section. It is obtained from a predetermined database containing all the single reinforced design sections for beam and columns subjected to axial load, uniaxial or biaxial moments. The designed optimum beam sections by using GAs have been unified through MATLAB to satisfy axial, flexural, shear and torsion requirements based on the designed code. The frames' functional cost has contained the cost of concrete and reinforcement of steel in addition to the cost of the frames' formwork. The results have found that limiting the dimensions of the frame's beams with the frame's columns have increased the optimum cost of the structure by 2%, declining the re-analysis of the optimum designed structures through GA.

• The Journal of Internal Korean Medicine
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• v.36 no.2
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• pp.122-152
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• 2015

Objectives: This study was designed to develop a standard tool for pattern identification of gastroesophageal reflux disease (GERD) patients. Methods: Korean and Chinese literature was selected that mentioned pattern identification of GERD. We gathered the pattern identification and their symptoms and a Chinese medical doctor proficient in Korean translated the Chinese characters into Korean. A Korean linguist then confirmed the translation results to develop a draft of the standard tool for pattern identification of gastroesophageal reflux disease (PIGERD). The final PIGERD was developed after assessment by an expert committee composed of professors from the Korean Medicine University, using the following items: inclusion of the pattern identification and its symptoms, importance of items, and validity of translation. Results: Six pattern identifications and 94 symptoms were selected from 45 references and translated into Korean. Four pattern identifications [pattern/syndrome of liver qi invading the stomach (肝胃不和), spleen-stomach weakness (脾胃虛弱), spleen-stomach dampness-heat (脾胃濕熱), and stomach yin deficiency (胃陰不足)] and 49 symptoms were then selected through the Delphi method by the expert committee. The final standard PIGERD tool was completed after the assessment of translation validity and reflection of individual opinions by the expert committee. This tool consists of 40 items including tongue and pulse diagnosis. The weighted value was also computed from assessment of the importance of items. Conclusions: We developed a standard tool for pattern identification of gastroesophageal reflux disease (PIGERD) to clarify the pattern identification of patients with gastroesophageal reflux disease for standardized diagnosis.

• Journal of Sericultural and Entomological Science
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• v.35 no.2
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• pp.79-85
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• 1993

Winter dormancy of the mulberry(Morus species) in Suwon was investigated with regards to mulberry varieties, such as Kaeryangppong, Daeryunppon, Yongchionppong and Hongolppong application of fertilizers and growth hormone. In general, It initiated at late September and it subsequently became deeper and reached the highest degree through late October to early November. After that early November it gradually turned into the breaking state and was terminated by late November. Intensity and duration of dormancy were lower and shorter in Kaeryangppon. The standard application of N. P. K(30-13-18kg/10a) affects it delayed, but terminated earlier. On the other hand, the double amount of nitrogen affects the dormancy fast, but terminated late. The treatments of GA3 at the early and termination stages increased the bad sprouting. The contents of RNA and protein in the bark gradually increased as the dormancy becomes deeper.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.5
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• pp.433-441
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• 2011

The optimization of a centrifugal compressor was conducted. The ANN (Artificial Neural Network) was adopted as an optimization algorithm, and it was learned and trained with the DOE (Design of Experiment). In the DOE, it was predicted the main effect and the interaction effect of design variables to the objective function. The ANN was improved in the optimization process using the GA (Genetic Algorithm). When any output at each generation was reached a standard level, it was re-calculated by the CFD (Computational Fluid Dynamics) and it was applied to develop a new ANN. After 6th generation, the prediction difference between ANN and CFD was less than 1%. A pareto of the efficiency versus the pressure ratio was obtained through the 21th generation. Using this method, the computational time for the optimization was equivalent to the time consumed by the gradient method, and the optimized results of multi-objective function were obtained.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.4
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• pp.211-220
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• 2017

The application of the theoretical model to real assembly lines has been one of the biggest challenges for researchers and industrial engineers. There should be some realistic approach to achieve the conflicting objectives on real systems. Therefore, in this paper, a model is developed to synchronize a real system (A discrete event simulation model) with a theoretical model (An optimization model). This synchronization will enable the realistic optimization of systems. A job assignment model of the assembly line is formulated for the evaluation of proposed realistic optimization to achieve multiple conflicting objectives. The objectives, fluctuation in cycle time, throughput, labor cost, energy cost, teamwork and deviation in the skill level of operators have been modeled mathematically. To solve the formulated mathematical model, a multi-objective simulation integrated hybrid genetic algorithm (MO-SHGA) is proposed. In MO-SHGA each individual in each population acts as an input scenario of simulation. Also, it is very difficult to assign weights to the objective function in the traditional multi-objective GA because of pareto fronts. Therefore, we have proposed a probabilistic based linearization and multi-objective to single objective conversion method at population evolution phase. The performance of MO-SHGA is evaluated with the standard multi-objective genetic algorithm (MO-GA) with both deterministic and stochastic data settings. A case study of the goalkeeping gloves assembly line is also presented as a numerical example which is solved using MO-SHGA and MO-GA. The proposed research is useful for the development of synchronized human based assembly lines for real time monitoring, optimization, and control.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.1
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• pp.21-34
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• 2008

An improved optimum design method for reinforced concrete frames using integrated genetic algorithm(GA) with direct search method is presented. First, various sets of initially assumed sections are generated using GA, and then, for each resultant design member force condition optimum solutions are selected by regression analysis and direct search within pre-determined design section database. In advance, global optimum solutions are selected from accumulated results through several generations. Proposed algorithm makes up for the weak point in standard genetic algorithm(GA), that is, low efficiency in convergence causing the deterioration of quality of final solutions and shows fast convergence together with improved results. Moreover, for the purpose of elevating economic efficiency, optimum design based on the nonlinear structural analysis is performed and therefore makes all members resist against given loading condition with the nearest resisting capacity. The investigation for the effectiveness of the introduced design procedure is conducted through correlation study for example structures.