• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.574-577
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• 1995

The proposed method is described for scheduling their output of thermal power units so as to comply with total emission constraint, area emission constraint and the both of those constraints. Also, by using a trade-off curve, representing all dispatch alternatives and conflict between the emission and the fuel cost, the sensitivity analysis of the emission and the fuel cost is applied to this algorithm. By the way, this proposed method is analyzed how dispatch changes as a function of the total environmental cost, and as a function of the relative weighting of individual environmental insults, e.g, NOx and $SO_{2}$. By applying the proposed method to the system, the usefulness of this method is verified.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.9
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• pp.494-499
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• 2004

This paper presents to compute the power economic dispatch, an optimal power flow (OPF) computation algorithm, considering the load power factor limits constraint in developed. Efficient reactive power planning enhances economic operation as well as system security. Accordingly, an adequate level of power factor limits for the load busesshould be evaluated for economic operation. In this paper, the ranges of acceptable load power factors are portrayed as bandwidths of load power factor expressed as a function of load level. The load power factor limits are included and described into the OPF's objective function. The method Proposed is applied to IEEE 26 bus system.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.98-100
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• 2003

This paper presents the method for computing the power economic dispatch with an optimal power flow (OPF) computation algorithm, considering the power factor limits constraint. Efficient reactive power planning enhances economic operation as well as system security. Accordingly, an adequate level of power factor limits for the load buses should be evaluated for economic operation. The power factor limits are included and described into the OPF's objective function. The proposed method is applied to IEEE 26 buses system.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1064-1072
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• 2017

The power of controlled generators in microgrids randomly fluctuate because of the stochastic volatility of the outputs of photovoltaic systems and wind turbines as well as the load demands. To address and dispatch these stochastic factors for daily operations, a dynamic economic dispatch model with the goal of minimizing the generation cost is established via chance-constrained programming. A Monte Carlo simulation combined with particle swarm optimization algorithm is employed to optimize the model. The simulation results show that both the objective function and constraint condition have been tightened and that the operation costs have increased. A higher stability of the system corresponds to the higher operation costs of controlled generators. These operation costs also increase along with the confidence levels for the objective function and constraints.

• 재활복지
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• v.21 no.1
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• pp.253-277
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• 2017

The purpose of this study was to develop the Constraints in Physical Activity Scale for people with physical Disabilities(CPASD) which measures the constraints in physical activity of people with physical disabilities. For this study, the 5 step analytic framework of unified validity developed by Messick (1995), the framework for conducting a strong program of construct validation by Benson (1998) method were applied. Furthermore, the validity of CPASD was systematically presented by applying common factor model and measurement model to 264 persons with physical disabilities. The conclusion based on the results and discussions of this study is as follows. First, CPASD presented evidence of job validity. Four factors (17 items) were developed, consisting of leader constraints, economic constraints, prejudice, and exercise environment constraints through the analysis of the factor structure and the fit of factor coefficients. Second, the factor structure of the developed CPASD (leader constraint, economic constraint, prejudice, exercise environment constraint) was statistically distinguished and stably reflected the existing exercise participation constraints theory. Third, the developed CPASD presented evidence of the validity of the criteria. Leader constraints and prejudice were negatively correlated with positive motor emotions, leader constraints, prejudice, and exercise environment constraints were positively correlated with negative motor emotions. Therefore, in future research, it is necessary to reevaluate the current system and actual condition related to leader constraints, economic constraints, prejudices, and exercise environment constraints derived as factors of CPASD. To do this, it is necessary to judge the degree of reality based on the causal relationship verification and IRT theory using CPASD.

• Journal of the Korea Institute of Building Construction
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• v.3 no.2
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• pp.149-156
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• 2003

The purpose of this study was to find out the most reasonable design in the superstructure of an underground parking lot which needs to be considered with the economic efficiency being influenced on the subdivision price, construction duration, workability and the maintenance of crack and leakage status of apartment house. In this research, we've evaluated the fitness for the superstructure of an underground parking lot by examination of construction constraint, which was based on the calculated data of structural design and quantity survey. The results of this study are summarized as follows. 1. The system of the absent structure of beam is proper structure for economic efficiency, construction duration and workability, but it is disadvantageous at the side of maintenance efficiency because of the many part of large slab. In the opposite direction, the establishing structure of beam has the advantages of structural stability except economic efficiency, construction duration and workability 2. It's required a proper selection for the views being contrary to each other which the owners considers good quality, on the other hand, the contractors consider construction duration and workability. 3. In making a selection for the superstructure of an underground parking lot, we have concluded that it is the most important to choose the proper structure for the demanded performance by contrasting with two system. (2Bay or 3Bay)

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.656-659
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• 2005

his paper develops the systematic and quantitative priority-determining method for national investment using the framework of evaluating R&D. This study proposes multi criteria for evaluating the R&D of New & Renewable Energy through analysing the attribute of 11 types of energy. The framework is constituted by 4 criteria, the political urgency, economic impact, regional constraint. and technological attribute and the each criteria has 3 or 4 sub-criteria. These sub-criteria are weighted using AHP.

• Proceedings of the Korea Association of Information Systems Conference
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• 2004.11a
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• pp.37-41
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• 2004

The existing network can be expanded with addition of new nodes and multiple choices of link type for each nossible link. In this paper, the design problem of network expansion is defined as finding the network topology minimizing cost subject to reliability constraint. To efficiently solve the problem, an genetic algorithm approach is suggested.

• Korean Journal of Culture and Social Issue
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• v.29 no.1
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• pp.101-123
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• 2023

As an effort to further extend the existing understanding on the Psychology of Working Theory, this study examined gender differences in the paths to the attainment of decent work with Korean emerging adults. A total of 311 South Korean employees (mean age = 25.96, men = 94, women = 217) completed online questionnaires. We found that economic constraints inversely predicted work volition and career adaptability, which were positively relatedin turn, led to decent work. The overall indirect effect of work volition and career adaptability between economic constraints and decent work was significant., hHowever, the specific indirect effect of work volition and career adaptability was not significant. Further analyses showed a gender difference in the paths. Specifically, economic constraint was significantly negatively associated with work volition, and work volition predicted decent work only for women, but not for men. Moreover, economic constraint was significantly inversely associated with career adaptability, and career adaptability positively predicted decent work only for men, but not for women. Work volition mediated between economic constraints and decent work for women, while career adaptability had a mediating effect for men. It suggests that career resources for obtaining a decent work may be distinctive by genderdifferent groups.

• Journal of Electrical Engineering and Technology
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• v.4 no.3
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• pp.337-345
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• 2009

Deregulation in power industry has made the reactive power ancillary service management a critical task to power system operators from both technical and economic perspectives. Reactive power management in power systems is a complex combinatorial optimization problem involving nonlinear functions with multiple local minima and nonlinear constraints. This paper proposes a practical market-based reactive power ancillary service management scheme to tackle the challenge. In this paper a new model for voltage security and reactive power management is presented. The proposed model minimizes reactive support cost as an economic aspect and insures the voltage security as a technical constraint. For modeling validation study, two optimization algorithm, a genetic algorithm (GA) and particle swarm optimization (PSO) method are used to solve the problem of optimum allocation of reactive power in power systems under open market environment and the results are compared. As a case study, the IEEE-30 bus power system is used. Results show that the algorithm is well competent for optimal allocation of reactive power under practical constraints and price based conditions.