• Proceedings of the Korean Quaternary Association Conference
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• 2004.06a
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• pp.29-29
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• 2004

Long term observational analysis by climatologists has confirmedthat the global warming is no longer a topic of debate among scientists andpolicy makers. According to the report of IPCC-2001 (Intergovernmental Panelon Climate Change), the global mean surface air temperature is increasinggradually. The reported increase of mean temperature is by 0.6 degree in the end of twentieth century. This could represent severe threat for propertylosses especially due to increase in the number of extreme weather arising out of global warming. period of model integration from 2001 to 2100 using output of ECHAM4/HOPE-G of Max Planet Institute of Meteorology (MPI) for IPCC SRES (Special Report on Emission Scenarios). The main results of this study indicate increase of surface air temperature by 6.20C and precipitation by 2.6% over Korea in the end of 21st century. Simulation results also show that there is increase in daily maximum and minimum temperatures while decrease in diurnal temperature range (DTR). DTR changes are diminished mainly due to relatively rapid increase of daily minimum temperature than that of daily maximumtemperature. It has been observed that increase in precipitation amount anddecrease in the number of rainy days lead to increase of pre precipitationintensity.

• Journal of Labour Economics
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• v.34 no.3
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• pp.29-58
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• 2011

Using careful background research and methodology, we proposed a revised sectoral index of vulnerability that is directly applied to two central labor examples: working hours and minimum wages. The valued calculated by each specific index represent the degree of weakness in corresponding conditions at the level of workplace units. Our proposed vulnerability index promises to be applicable to all business units under labor spot inspection. Also, it can be easily updated as the business environment evolves. The index is useful in selecting certain groups of business units and in evaluating the effectiveness of each regional government office.

• Journal of the Korean Operations Research and Management Science Society
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• v.38 no.4
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• pp.11-33
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• 2013

We analyzed the structures and properties of the global financial market networks using social network analysis approach. The Minimum Spanning Tree (MST) lengths and networks of the global financial markets based on the correlation coefficients have been analyzed. Firstly, similar to the previous studies on the global stock indices using MST length, the diversification effects in the global multi-asset portfolio can disappear during the crisis as the correlations among the asset class and within the asset class increase due to the system risks. Second, through the network visualization, we found the clustering of the asset class in the global financial markets network, which confirms the possible diversification effect in the global multi-asset portfolio. Meanwhile, we found the changes in the structure of the network during the crisis. For the last one, in terms of the degree centrality, the stock indices were the most influential to other assets in the global financial markets network, while in terms of the betweenness centrality, Gold, Silver and AUD. In the practical perspective, we propose the methods such as MST length and network visualization to monitor the change of the correlation risk for the risk management of the multi-asset portfolio.

• Journal of Korea Foundry Society
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• v.10 no.3
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• pp.219-224
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• 1990

In this, we have investigated the solute behavior in front of solid-liquid interface according to the change of the cooling rate in bronze alloy and phosphor bronze alloy. The conclusive summary is as follows: 1) The secondary dendrite arm spacing was decreased with increasing the cooling rate. 2) The minimum solute concentration happened to along centerline of primary arm, and the maximum solute concentration was found at the boundary of arm or between the arms the minimum solute concentration was increased with the cooling rate. 3) Segregation Index S was decreased with increasing the cooling rate and content of P. 4) The degree of the microsegregation was decreased with increasing the cooling rate. The effective distribution coefficient, Ke was increased with addition of P in Cu-Sn.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.11
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• pp.1029-1037
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• 2010

If an internal combustion engine is operated by consolidated control, the minimum fuel consumption is achieved and the demanded objectives are satisfied. For this, it is necessary that the engine is operated on the ideal operating line which satisfies minimum fuel consumption. In this context of view, there are many tries to achieve given object. However, the parameters in the internal combustion engines are variable and depend on the operating points. Therefore, it is necessary to cope with the uncertainties such that the optimal operating may be possible. From this point of view, this paper gives a controller design method and a robust stability condition for engine torque control which satisfies the given control performance and robust stability in the presence of physical parameter perturbation. Exactly, in this paper, we consider the robust stability problem of this 2DOF servosystem with nonlinear type uncertainty in the engine system, and a robust stability condition for the servosystem is shown. This result guarantees that if the plant uncertainty is in the permissible set defined by the given condition, then a gain tuning can be carried out to suppress the influence of the plant uncertainties.

• Journal of Chest Surgery
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• v.7 no.1
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• pp.1-8
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• 1974

Acute pulmonary edema was induced by intravenous injection of epinephrine, intravenous infusion of dextran and intratracheal instillation of acid solution index was determined from pressure volume curves in excised lungs. Surface activity was also investigated with measurements of maximum and minimum surface tension and stability index on saline extracts of same lungs. The results were as follows. 1. The expansion index of excised lung in which pulmonary edema was induced by intravenous injection of epinephrine, intravenous infusion of dextran and intratracheal instillation of acid solution was ignificantly decreased as compared with the normal control of $0.86{\pm}0.017$ to $0.74{\pm}0.03$, $0.71{\pm}0.081$and $0.76{\pm}0.02$, respectively. 2. The deflation curves of excised lungs in which pulmonary edema was induced were significantly decreased as compared with the normal controls. 3. The minimum surface tension of excised lung in which pulmonary edema was induced was significantly increased in each groups and stability index was significantly decreased as compared with the normal controls 0.78 to $0.35{\pm}0.039$, $0.29{\pm}0.02 $ and $0.31{\pm}0.083$, respectively. 4. The decrease of pulmonary surface activity in acute pulmonary edema was in proportion to the degree of pulmonary edema regardless of their etiology.

• Architectural research
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• v.1 no.1
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• pp.47-53
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• 1999

An interesting of desktop air-conditioning system is the Personal Environmental Module(PEM) System. The PEM system allows the occupant to choose the desired temperature, air volume and direction of the discharged air. In this study, the measurements on the age of air and the air change effectiveness, using the tracer gas method, are carried out to analyze the ventilation performance for provision of fresh air near the breathing zone by the PEM. The relations between the PEM for optimal control and other factors related to indoor air quality, and the ventilation for the PEM are examined. Also, three different supply diffuser types(desktop, floor and ceiling) are compared in view of their ability to distribute supply air to the workstation breathing zone. The desktop diffuser type could deliver air directly to the occupants breathing zone with a high degree of effectiveness. The minimum local age of air was measured in the breathing zone, which is directly supplied with air from the PEM diffusers, and the measured local air change effectiveness of the desktop diffuser in the breathing zone was about 1.13 to 1.23 times greater than that of the ceiling and floor diffusers. When the minimum outside air change rate as specified using ASHRAE Standard 62R is supplied with a desktop diffuser type, the volume of outside air can be reduced 13 to 23%, resulting in a commensurate in ventilation energy use.

• School Mathematics
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• v.7 no.4
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• pp.353-373
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• 2005

The purpose of this paper is to analysis the basic network problem which can be applied to the mathematically gifted students in elementary school. Mainly, we discuss didactic transpositions of the double counting principle, the game of sprouts, Eulerian graph problem, and the minimum connector problem. Here the double counting principle is related to the handshaking lemma; in any graph, the sum of all the vertex-degree is equal to the number of edges. The selection of these subjects are based on the viewpoint; to familiar to graph theory, to raise algorithmic thinking, to apply to the real-world problem. The theoretical background of didactic transpositions of these subjects are based on the Polya's mathematical heuristics and Lakatos's philosophy of mathematics; quasi-empirical, proofs and refutations as a logic of mathematical discovery.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.11 no.1
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• pp.82-91
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• 2004

Purpose: The purpose of this study was to identify health promoting behavior and life satisfaction in rural elderly people. Method: The data were collected from October 1st 2002 to October 31th, 2003. The participants were 142 elderly people living in Hong Cheon, Korea. Data were collected using structured questionnaires and analyzed using the SPSS program. Result: The average score for the health promoting behavior was 2.64 (${\pm}0.34$), with a minimum of 1.48 and maximum of 3.80. The average scores for each subscale were, nutrition, 2.98, interpersonal support, 2.78, health responsibility, 2.67, self-actualization, 2.66, stress management, 2.58, and exercise, 1.93. Signifiant differences in health promoting behavior were found according to the following general characteristics: education level, religion, senior citizens center usage and allowance. The average score for life satisfaction was 2.68 (${\pm}0.42$), with a minimum of 1.38 and a maximum of 3.85. Senior citizens center usage was the only general characteristics that showed a significant difference for life satisfaction. There was a significant positive correlation between health promoting behavior and life satisfaction (r= 0.5783, p=0.001). Self-actualization and stress management had statistically significant casual effects on life satisfaction ($R^2$=0.3961). Conclusion: Effective methods to enhance life satisfaction of rural elderly should emphasize self-actualization and stress management.

• Journal of KIISE:Computer Systems and Theory
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• v.35 no.2
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• pp.60-65
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• 2008

The matching preclusion set of a graph is a set of edges whose deletion results in a graph that has neither perfect matchings nor almost perfect matchings. The matching preclusion number is the minimum cardinality over all matching preclusion sets. We show in this paper that, for any $m{\geq}4$, the matching preclusion numbers of both m-dimensional restricted HL-graph and recursive circulant $G(2^m,4)$ are equal to degree m of the networks, and that every minimum matching preclusion set is the set of edges incident to a single vertex.