• Proceedings of the KIEE Conference
• /
• 1999.07c
• /
• pp.1506-1509
• /
• 1999

This paper presents a new economic dispatch algorithm to improve the unit commitment solution while guaranteeing the near optimal solution without reducing calculation speed. The conventional economic dispatch algorithms have the problem that it is not applicable to the unit commitment formulation due to the frequent on/off state changes of units during the unit commitment calculation. Therefore, piecewise linear iterative method have generally been used for economic dispatch algorithm for unit commitment. In that method, the approximation of the generator cost function makes it hard to obtain the optimal economic dispatch solution. In this case, the solution can be improved by introducing a inverse of the incremental cost function. The proposed method is tested with sample system. The results are compared with the conventional piecewise linear iterative method. It is shown that the proposed algorithm yields more accurate and economical solution without calculation speed reduction.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2002.08a
• /
• pp.835-837
• /
• 2002

The 17" Backlight Unit (BLU) employing twelve EEFLs (External Electrode Fluorescent Lamp) has been developed for LCD-TV The characteristics of the EEFL BLU without dual brightness enhancement film (DBEF) were equivalent to those of CCFL (Cold cathode Fluorescent Lamp) BLU employing eight CCFLs with DBEF. Luminance, power consumption and uniformity were 12,000nits, 32watt and 80%, respectively. The inverter of EEFL Backlight Unit is composed of 2 transformers and driven by the sinusoidal waveform.

• Elastomers and Composites
• /
• v.50 no.2
• /
• pp.87-91
• /
• 2015

Cure characteristics of non-oil-extended solution SBR (S-SBR_NO) and oil-extended solution SBR (S-SBR_ EO) compounds reinforced with silica/carbon black were investigated. Minimum and maximum torques of S-SBR_ EO compounds were much smaller than those of S-SBR_NO ones. Delta torques of S-SBR_NO compounds were greater than those of S-SBR_EO ones, and that of S-SBR_NO compound increased with increase in the 1,2-unit content. Optimum cure time ($t_{90}$) of S-SBR compound decreased with increase in the 1,4-unit content, whereas it increased with increase in the 1,2-unit content. Cure rate index of S-SBR compound increased with increase in the 1,4-unit content, whereas it decreased with increase in the 1,2-unit content. Comparing cure characteristics of S-SBR_NO and S-SBR_EO compounds with the same 1,2-unit content, $t_{90}$s of S-SBR_EO compounds were longer than those of S-SBR_NO ones and cure rate indices of S-SBR_EO compounds were smaller than those of S-SBR_NO ones.

• Nuclear Engineering and Technology
• /
• v.49 no.2
• /
• pp.286-294
• /
• 2017

The events at the Fukushima Daiichi Nuclear Power Station in March 2011 point out, among other matters, that concurrent accidents at multiple units of a site can occur in reality. Although site risk has been deterministically considered to some extent in nuclear power plant siting and design, potential occurrence of multi-unit accident sequences at a site was not investigated in sufficient detail thus far in the nuclear power community. Therefore, there is considerable worldwide interest and research effort directed toward multi-unit site risk assessment, especially in the countries with high-density nuclear-power-plant sites such as Korea. As the technique of probabilistic safety assessment (PSA) has been successfully applied to evaluate the risk associated with operation of nuclear power plants in the past several decades, the PSA having primarily focused on single-unit risks is now being extended to the multi-unit PSA. In this paper we first characterize the site risk with explicit consideration of the risk associated with spent fuel pools as well as the reactor risks. The status of multi-unit risk assessment is discussed next, followed by a description of the emerging issues relevant to the multi-unit risk evaluation from a practical standpoint.

• Communications of the Korean Mathematical Society
• /
• v.12 no.2
• /
• pp.427-456
• /
• 1997

This paper concerns constructing wavelet bases on the unit interval, where a new boundary treatment is provided to overcome certain drawbacks of eariler constructions. Wavelet expansions on the unit interval usually suffer from artificial boundary effects and poor convergence at the boundaries. Many researchers have suggested a solution to the drawbacks. From a practical point of view, their solutions also have a common disadvantage. This paper provides a new solution using biorthogonality near the boundaries, that avoids the disadvantage while preserving their advantages.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.49 no.2
• /
• pp.70-77
• /
• 2000

This paper proposes a method of solving a unit commitment problem using tabu search (TS) which is heuristic algorithm. Ts is a local search method that starts from any initial solution and attempts to determine a better solution using memory structures. In this paper, to reduce the computation time for finding the optimal solution, changing tabu list size as intensification strategy and path relinking method as diversification strategy are proposed. To show the usefulness of the proposed method, we simulated for 10 units system and 110 units system. Numerical results show improvements in the generation costs and the computation time compared with priority list, genetic algorithm(GA), and hybrid GA.

• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.1609-1612
• /
• 1997

Kinematically redundantant manipulators have a nimber of potential advantages over nonredundant ones. Questions associated with manipulability measures for (non)redundant manipulators derived by minimum 2-norm solution and minimum infinity-norm solution in unit joint velocity are examined in detail.

• Korean Journal of Adult Nursing
• /
• v.16 no.3
• /
• pp.452-459
• /
• 2004

Purpose: To investigate the effect of oral care either with normal saline or with tantum solution on the oral state of the patients in intensive care unit as well as the frequency of bacteria occurrence inside their oral cavities. Method: The study was performed from March thru May of 2003 on the nonequivalent control group non-synchronized quasi-experimental design. Forty subjects were selected for each group. The data were analyzed using the SPSS 10.0 Win. The pre-experimental homogeneity and post-experimental differences between the two groups were analyzed with t-test. Result: There was a significant difference in the oral cavity state between the experimental group that had used normal saline and the control group that had used tantum solution. Conclusion: Based on the results described above, it is considered that normal saline is more effective than the tantum solution for the oral care of the patients in intensive care unit.

• Journal of Biosystems Engineering
• /
• v.32 no.4
• /
• pp.263-268
• /
• 2007

An auto sampling and filtering unit was developed for monitoring automation of a fermentation process and its performance was evaluated. The automatic sampling and filtering unit was constructed with a glass filter, a diaphragm suction pump, and a flow direction change valve. To evaluate operating stability, delivery volumes of the suction pump were measured according to the experimental conditions of cellulose powder, pore size of the glass filter and suction head of the pump. The developed unit could deliver the sample solution under any experimental conditions except the filter pore size of $16{\mu}m$ and the suction head of 20cm. In case of the suction head of 30cm, the pump could not deliver the sample solution at all. Concentrations of the sample solutions were converged on those of the standard glucose solution after 8 minutes from the initial sampling time. The relative error of concentration between the sample and the standard solution showed 3.8, 4.8, 7.0% for the 1, 3, 5% contents of cellulose powder, respectively.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2006.07a
• /
• pp.616-616
• /
• 2006