• Proceedings of the Korean Society of Life Science Conference
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• 2003.05a
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• pp.60-60
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• 2003

• Korean Journal of English Language and Linguistics
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• v.2 no.1
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• pp.23-30
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• 2002

Phonologically, the difference between the English stops /b, d, g/ and /p, t, k/ is carried by the presence or the absence of the vocal fold vibration throughout their oral closure phase. If phonology has its foundation in phonetics, there must be phonetic evidence for the voiced-voiceless distinction. This study is aimed to determine whether or not the voiced-voiceless distinction is acceptable or proper in English. The determination was based mainly on findings in the existing literature and in informal experiments. In conclusion, there is no phonetic evidence for the voiced-voiceless distinction both in production and perception. The [voice] appears to be one of potential phonetic correlates of the phonologically voiced stop. It is improper to use the [voice] as independent phonological marker, regardless of position (word-initial, intervocalic, word-final). A feature other than the voiced-voiceless feature must distinguish /b, d, g/ from /p, t, k/.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.893-894
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• 2006

This paper presents a design and analysis solutions for the general class and control parameter estimation of slotted iron-cored Permanent Magnet Linear Synchronous Motor with Halbach magnetization stator and 3-phase winding mover. In our design and analysis, stator consisting of permanent magnets and slotted iron-cored coil mover are treated in a uniform way via magnetic vector potential. For one such motor structure, we give analytical formulas for its magnetic field, back electromotive force and trust force. Moreover, the detent force are calculated by the relative permeance function. In good agreement with the estimated values from the analyses, the experimental results and Finite Element Method (FEM) confirm the validity of the design and analysis framework.

• Nuclear Engineering and Technology
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• v.28 no.6
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• pp.522-531
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• 1996

The adoption of expert systems mainly as operator supporting systems is becoming increasingly popular as the control algorithms of system become more and more sophisticated and complicated. The verification phase of knowledge base is an important part for developing reliable expert systems, especially in nuclear industry. Although several strategies or tools have been developed to perform potential error checking, they often neglect the reliability of verification methods. Because a Petri net provides a uniform mathematical formalization of knowledge base, it has been employed for knowledge base verification. In this work, we devise and suggest an automated tool, called COKEP(Checker Of Knowledge base using Extended Petri net), for detecting incorrectness, inconsistency, and incompletensess in a knowledge base. The scope of the verification problem is expanded to chained errors, unlike previous studies that assume error incidence to be limited to rule pairs only. In addition, we consider certainty factor in checking, because most of knowledge bases have certainty factors.

• Journal of the Korea Safety Management & Science
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• v.14 no.2
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• pp.245-252
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• 2012

The biggest difficulty the small and small business currently face is not to have the effective cusomer management system that is the computerization of management. This suggests their will to introduce data marketing in order to differentiate 'Customer Marketing' and 'One to One Marketing'. The potential needs as well as visible needs of customer should be considered in order to research and analyze the customer data. At this point mayor enterprises are paying much attention to Customer Segmentation and their related markets are expanding rapidly. I'll give a brief introduction to the Multi Criteria Importance-Performance Analysis and go into the problems that should be considered and which phase to emphasize when building this system.

• Journal of the Korean Solar Energy Society
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• v.27 no.4
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• pp.51-58
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• 2007

Gas hydrate is a special kind of inclusion compound that can be formed by capturing gas molecules to water lattice in high pressure and low temperature conditions. When referred to standard conditions, $1m^3$ solid hydrates contain up to $172Nm^3$ of methane gas, depending on the pressure and temperature of production. Such large volumes make natural gas hydrates can be used to store and transport natural gas. In this study, three-phase equilibrium conditions for forming methane hydrate were theoretically obtained in aqueous single electrolyte solution containing 3wt% NaCl. The results show that the predictions match the previous experimental values very well, and it was found that NaCl acts as an inhibitor.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1128-1130
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• 2008

Bimodal tram is a new public transportation to improve the existing traffic system. The purpose of this study was to investigate the environmental characteristics of the developed bimodal tram through its life cycle. The used tool was life cycle assessment (LCA), which could evaluate environmental loads quantitatively for a product. Based on bill of material (BOM), the environmental impacts of bimodal tram was calculated from manufacturing to operating phase. Among impact categories, photochemical oxidant creation potential (POCP) was the highest, which was resulted from the manufacturing and the combustion of CNG used as a fuel of bimodal tram. In the future, the application of LCA results can enhance increasingly the environment of bimodal tram as an environmental-friendly transportation.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.9
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• pp.863-871
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• 2004

The use of fossil fuels like coal, oil and natural gases around the world causes an increase of the carbon dioxide content in the atmosphere. In order to reduce the concentration of the greenhouse gas, the idea of carbon dioxide sequestration in the ocean is proposed to be an effective mitigation strategy to counteract potential global warming due to the greenhouse effect. Therefore, in the present study, calculations of the dissolution behavior of carbon dioxide when liquid carbon dioxide is released at 1,000m and 1,500m in depth by fixed pipeline are performed. The results show that carbon dioxide droplets change to carbon dioxide bubbles in gas phase around 500m in depth, and the droplets are completely dissolved below 500 m in depth if the liquide carbon dioxide is released both at 1,000 m in depth with the initial diameter of 0.007m or less and at 1,500m in depth with the diameter of 0.011m or less.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.7 no.3
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• pp.512-520
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• 1995

This study investigates the simultanceous heat and mass transfer between a falling desiccant film and air in cross flow at the interface. The application of this work is the optimization of falling film evaporators for use in potential hybrid air conditioning systems. The specific geometry considered is liquid TEG films falling along the vertical cooled surfaces of a channel with air in cross flow. The equations to describe the coupled heat and mass transfer between a falling desiccant film and air in cross flow for a falling film evaporator have been presented and solved numerically. The effects of important design and operating variables on the evaporator performance predicted by the parametric numerical analysis and suggestions for performance improvements of the evaporator are presented.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.12
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• pp.883-888
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• 2007

As a starting point of investigating what molecular dynamic simulations can reveal about the nature of atomic level of heating and cooling process, argon described by the LJ potential is considered. Stepwise heating and cooling of constant rates are simulated in the NPT (constant number, pressure and temperature) ensemble. Hysteresis is found due to the superheating and supercooling. Drastic change of volume and energy is involved with phase change, but the melting point can not be obtained by simply observing the changes of these quantities. Since liquid and solid phases can co-exist at the same temperature, Gibbs free energy should be calculated to find the temperature where the Gibbs free energy of liquid is equal to that of the solid since the equilibrium state is the state of minimum Gibbs free energy. The obtained melting temperature, $T^*=0.685$, is close to that of the experiment with only 2% error.