• Journal of the Korean Chemical Society
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• v.41 no.8
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• pp.427-436
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• 1997

A simple relation exists between electronegativities of cations and their oxidation states and ionic radii. An empirical law is proposed: X = 0.274 z-0.15 z r - 0.01 r+1+${\alpha}$, z being oxidation number, r ionic radius in $\AA$ and ${\alpha}$ a term related to the atomic number. this relation permits to calculate an electronegativity scale covering a large set of electronic and crystallographic situations. An application to the calculation of acid strengths of cations is presented.

• Journal of the Korean Mathematical Society
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• v.37 no.6
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• pp.943-956
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• 2000

We investigate a relation between multiplicity of solutions and source terms of jumping problem in wave equation when the nonlinearity crosses an eigenvalue and the source term is generated by finite eigenfunctions. We also show that the jumping problem has infinitely many solutions when the source term is positive multiple of the positve eigenfunction.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1994-1999
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• 2003

This paper discusses dynamic characteristics of motion of a pair of multi-degrees of freedom robot fingers executing grasp of a rigid object and controlling its orientation with the aid of rolling contacts. In particular, the discussions are focused on a problem of gain-tuning of sensory feedback signals proposed from the viewpoint of sensorymotor coordination, which consist of a feedforward term, a feedback term for controlling rotational moment of the object, and another term for controlling its rotational angle. It is found through computer simulations of the overall fingersobject dynamics subject to rolling contact constraints that some dynamic characteristics of torque-angular velocity relation may play an important role likely as reported by experimental results in muscle physiology and therefore selection of damping gains in angular velocity feedback depending on the guess of object mass is crucial. Finally, a guidance of gain-tuning in each feedback term is suggested and its validity is discussed by various computer simulations.

• Korea Journal of Hospital Management
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• v.19 no.4
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• pp.34-44
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• 2014

The objective of this study is to analyze the effects of DINESCAPE on patient satisfaction and the intention of maintaining long-term relationship for Chinese Patients who received medical services at plastic surgery clinics in South Korea. For an empirical analysis, a total of 250 respondents were surveyed from may 1 to october 20, 2014. Of these, 200 respondents were considered to be reliable for statistical analysis. According to the analysis results, among the components of DINESCAPE, atmosphere, cleanliness, convenience and accessibility, employees service, and the convenience of using the websites had positive effects on patient satisfaction, which exerted a positive effect on the intention of maintaining long-term relationship with patients.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.1
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• pp.31-37
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• 2019

This study investigates the effects of long-term artificial-aging on hardness variation in the dissimilar metal weldments for nuclear power plant facilities. These dissimilar welds are inevitably required to join the components in nozzle parts of pressurized vessels, such as austenitic stainless steels and ferritic steels. A artificial thermal aging was conducted in an electrical furnace to simulate material degradation at high temperatures. The test materials were held at the temperature of $600^{\circ}C$ for 10000 hours and interrupted at various levels of degraded specimens. The degradation of hardness is a well-known phenomenon resulting from long-term aging or high-temperature degradation of structural materials. In this study, the variation of hardness at each position was different, and complicated in relation to microstructures such as twins, grains, precipitates, phase transformations, and residual stresses in dissimilar weldments. We discussed the variation of hardness in terms of microstructural changes during long-term aging.

• The Journal of Korean Association of Computer Education
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• v.19 no.3
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• pp.11-19
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• 2016

Enhancement of computing education became an international phenominon including South Korea's revised national curriculum 2015. As the enhancement begins to focus on universal computing education, researches to investigate long-term effect of the enhancement is needed. To explore whether the reinforced computing education will bring which long-term impacts, this study investigated university students' experience on computer subject in their secondary schools, and major selection and achievement in a college computing course. As results, there was no statistically significant relation of taking the computer subject per se and major selection and achievement, but significant relation between contents of the subject, and major selection and achievement. This study has limitation on design and results lacking longitudinal data but contributes emphasizing need of longitudinal study to measure long-term effect of enhancement of computing education and providing clues of what impact it would bring.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.4
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• pp.476-490
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• 1991

Although various technical details of the surgical procedures have been improved, Skeletal relapse is the most noteworthy complication of orthognathic surgery. It seems to be an imbalance of the perioral muscular groups resulting from changes in the cavitas oris propria after surgery. Among other factors, it is widely known with the changes of tongue posture, as indicated by the hyoid position. Ten patients that had undergone mandibular setbacks by way of Modified Obwegeser method were evaluated retrospectively. The serial cephalometric films were taken preoperatively, immediately postoperatively, after removal of IMF, and at a subsequent long-term follow-up period. The cephalometric evaluation of tongue posture were based on stable craniofacial landmarks. The relation between the 2-dimensional changes of tongue posture and hyoid position and the relapse of mandibular setback are discussed. Anatomic changes that were found to accompany such setback are as follows. 1.There are 2 cases of relapse in 10 patients at long-term follow-up(20%) 2.The tongue was moved posteriorly and its size was reduced anteriorly and posteriorly at immediate postoperative change and then the mandible shifted slightly toward the preoperative position, but the long was adapted to its new environment due to changing the position of its posterior part, and also the hyoid that moved posterioly and inferiorly was stabilized sightly posteriorly than its original position. 3.On the distance change of the suprahyoid muscle, the distance of P-H, ST-H was increased at immediate postoperative change(p<0.01) and decreased at IMF period(p<0.001), but the distance of H-Me, H-Ge was slightly decreased at IMF and long-term period(p<0.05). 4.On the width change of the pharyngeal air way, the width of the upper part of the pharyngeal space was lightly contracted at IMF and long-term period(p<0.05). 5.On the relation between mandibular setback and tongue posture and hyoid position, the significant correlation was found between the changes of some parts of mandibular setback and those of tongue posture, and not found those of hyoid position.

• Environmental and Resource Economics Review
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• v.29 no.2
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• pp.195-217
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• 2020

The improvement of energy intensity is drawing attention as a way to achieve sustainable development. Energy price and technology level are the main factors affecting energy intensity, and empirical studies on the relationship between the variables have been conducted mainly in overseas countries. However, analyzing the relation between energy intensity, energy price and technology has not been studied in Korea. Therefore, this study analyzed the dynamic relationship between energy intensity, energy price, and total factor productivity (TFP) in Korea. As a result of the analysis, the three variables form a long-term equilibrium relationship. The increase in TFP reduces energy intensity in both short and long term, and the long-term effect is greater than short-term effect. On the other hand, energy price do not have a significant impact on energy intensity. Granger causality test results show that energy intensity and TFP granger cause each other, but energy price is weak-exogenous.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.2
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• pp.212-217
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• 2009

There are rule-based learning method and statistic based learning method and so on which represent learning method for hierarchy relation between domain term. In this paper, we propose to leveling and similarity measure using the extended AHP of fuzzy term in Information system. In the proposed method, we extract fuzzy term in document and categorize ontology structure about it and level priority of fuzzy term using the extended AHP for specificity of fuzzy term. the extended AHP integrates multiple decision-maker for weighted value and relative importance of fuzzy term. and compute semantic similarity of fuzzy term using min operation of fuzzy set, dice's coefficient and Min+dice's coefficient method. and determine final alternative fuzzy term. after that compare with three similarity measure. we can see the fact that the proposed method is more definite than classification performance of the conventional methods and will apply in Natural language processing field.

• Proceedings of the Korea Contents Association Conference
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• 2006.11a
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• pp.84-89
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• 2006

Keeping pace with the speed of development of science & technology domain, the domain terms continuously repeat the step of creation and extinction. This study tries to define term life cycle and analyze extracted terms from a large corpus with the viewpoint. We chose 'ETNEWS' corpus which includes about 17 million Eojeols for 12 years because it is easy to inspect the transition of term life cycle and the corpus represents computer, IT, and electrotechnology domains. This study acquired several useful conclusions including the relation between specificity and life of terms. We expect that term life cycle will contribute to analyze the competition of similar technologies and determine which term be registered into general dictionary.