• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.139-139
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• 2012

With angle resolved photoemission spectroscopy (ARPES), the surface electronic band structures of Pt3Co (111) and Pt3Ni (111) single crystals are investigated, which allow to study the bonding interaction between chemically absorbed atomic oxygen and its surfaces. The d-band electrons of subsurface TM are separated from the direct chemical bonding with atomic oxygen. That is, the TM does not contribute to direct chemical bonding with oxygen. From the density functional theory (DFT) calculations, it is identified that the main origin of improved oxygen absorption property, i.e. softening of Pt-O bonding, is due to the suppression of Pt surface-states which is generated from change of interlayer potential, i.e. charge polarization, between Pt-top and TM-subsurface. Our results point out the critical roles of subsurface TM in modifying surface electronic structures, which in turn can be utilized to tune surface chemical properties.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1991.10a
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• pp.133-138
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• 1991

The aim of the present paper is to develop a computer program predicting ultimate fracture strength of initially cracked structure under monotonically increasing external loads. For this purpose, two kinds of 3-D isoparametric solid elements, one 6-node wedge element and another 8-node brick element are formulated along the small deformation theory. Plasticity in the element is checked using von Mises' yield criterion. Elasto-plastic stiffness matrix of the element is calculated taking account of strain hardening effect. If the principal strain at crack tip which is one nodal point exceeds the critical strain dependin on the material property, crack tip is supposed to be opened and the crack tip node which was previously constrained in the direction perpendicular to the crack line is released. After that, the crack lay be propagated to the adjacent node. Once a crack tip node is fractured, the energy of the newly fractured node should be released which is to be absorbed by the remaining part. The accumulated reaction force which was carried by the newly fractured node so far is then applied in the opposite direction. During the action of crack tip relief force, since unloading may be occured in the plastic element, unloading check should be made. If a plastic element unloads, elastic stress-strain equation is used in the calculation of the stiffness matrix of the element, while for a loading element, elasto-plastic stress-strain equation is continuously used. Verification of the computer program is made comparing with the experimental results for center cracked panel subjected to uniform tensile load. Also some factors affecting ultimate fracture strength of initially cracked plate are investigated. It is concluded that the computer program developed here gives an accurate solution and becomes useful tool for predicting ultimate fracture load of initially cracked structural system under monotonically increasing external loads.

• Journal of Korean Society of Transportation
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• v.28 no.6
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• pp.75-84
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• 2010

Controlled traffic intersection is critical point in terms of transportation network performance, where the most of traffic congestion arises. One of the most important and favorable measure of effectiveness in the signal controlled intersection is approach delay. Although lots of efforts to develop traffic delay estimation models have been made throughout the years, most of them were focusing on homogeneous traffic flow. The purpose of this research is to develop a traffic delay estimation model for traffic flow mixed with bus based on the horizontal shockwave theory. Traffic simulation is performed to test the adaptation level of the model in generic environment. The result shows that the delay increases with increasing bus traffic. Overall model accuracy comparing simulation result is acceptable, that shows the error range around 10 percent.

• International Journal of Costume and Fashion
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• v.5 no.1
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• pp.14-25
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• 2005

The objective of this study is to understand bodily extension and identity in contemporary fashion art through the analysis of 'the fashion acting on the body' among the fashion theory excluding body and the conspicuous works on the opening and covering images as a fashion art as a body-space'. This study also investigated identity problems where there are poles apart in opening and closure their bodies and body-space in which its clothing types were distorted by being de-bodilization out of the traditional and ideological expression method in contemporary fashion art from a opening and closure point of view. Image of opening and closure among body-space in fashion art can be classified into opposing structure of opening and closure. Destroying the boundary between bodily opening and closure for a primary function of clothing and dismantling the role and boundary between body and clothing, opening body-space in appearance as a reemergence of body image or the border between inner and outer are being ambiguous because of transparent material. Being representative work of this study opening body-space was expressed as an opening space image using transparency. On the contrary, closure body-space was isolated from external environment and confined in the certain space, which could limit or restraint body- action. Excluding boundary of body and clothing on the whole or in part, boundary of work becomes body-space. However, these were appeared to be a work inducing unlimited curiosity and meaning from the audience. The interpretation of artistic and body-space in fashion art are indicating the role and function of the fashion art exceeding the suggestible dimensions in the every day life of fashion. The body-space of fashion art showing similar aspect of body art today could be understood that it is substituted into an metaphorical, critical space by seeing it as a symbol system connected with social space. Therefore, contemporary fashion art should be interpreted as an equivocal space looking at the body-space with open mind.

• The Journal of Information Systems
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• v.18 no.1
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• pp.1-24
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• 2009

Recently many companies have increased their investment in IT because they are increasingly interested in taking advantage of IT and they recognized that it was a very important strategic resource that any organization should manage. That means that the members of a company or an organization realized the importance of IT specialists' coordinating and working in partnership with the business employees to ascertain the high quality and productivity through IT services. While the company looks at IT cost reduction, there is a pressure from users for more support and service from IT departments. That means IT service providers have to offer improved service quality at reasonable cost. To solve the contradictory problem, this paper proposes the application of IT service management. If the IT service management is implemented properly, an organization can attain the tangible and intangible results which are profitable and effective. In Korea, studies on IT service management have focused only on getting a certification and development issues, and there are few papers which accomplished empirical studies. From the viewpoint of Resource-based theory, this study reviews the definition of IT service management and its elements. It has demonstrated empirically how IT service management can have an impact on IT service management performance. As a result, IT service management plays a role in adding and improving the practical use and efficiency of IT service management. In conclusion, this study contributes to support and show the critical point of the previous literatures about IT service management and offers the new practical implications for business sectors.

• The Journal of Information Systems
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• v.20 no.3
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• pp.257-277
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• 2011

The current study categorizes factors of smartphone into three, using KANO model: attractive factors which cause only product satisfaction, must-be factors for dissatisfaction, and one-dimensional factors for both. Based on it, it presents a new model for the effects that smartphone factors have on satisfaction or dissatisfaction. The purpose is to theoretically explain that smartphone factors on which companies and users place a high value can actually affect satisfaction or dissatisfaction. After choosing 15 factors out of 25 which had been selected through literature study, these were divided into attractive, must-be, and one-dimensional ones. 93 out of 109 questionnaires returned were used for analysis. After frequency analysis using SPSS were conducted on the surveys, the factors were grouped, based on KANO table. The grouping results are as follows. Attractive factors include 'expansion slots for external memory, battery desorption, brand awareness, mobile banking and internet telephony'. Must-be ones include 'multi-touch, information security, entertainment, information retrieval, location based service and SNS. Finally, 'screen visibility, size of internal memory, the amount of internal memory, battery life, and response to after-sales service' are classified as one-dimensional factors. A critical finding of this paper is that since the results are different depending on the operating system of smartphones, it must be taken into consideration in studies on smartphones. The wide and rapid spread of smartphones has changed people's lifestyle as well as business environment, which forces companies to compete with each other to adapt to the changed circumstances. In this competitive system, studies on smartphone factors of satisfaction and dissatisfaction are essential for firms to establish a new strategy. From this point of view, the present paper is expected to be a basic material for enterprises not only to develop goods and services that maximize customer satisfaction and minimize dissatisfaction, but also to establish the future business strategy.

• Journal of Engineering Education Research
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• v.5 no.1
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• pp.50-58
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• 2002

The most important point in electronic learning(e-learning) is to gain the learning sympathy by improving interaction among the learners, instructors and operators around instruction contents. But it is necessary for the instructor to have active assistance of an administrator as a supporter and an operator because instructors do not accept all the learner's demands. So, operator's activity is very critical in success of e-learning. In this paper, wamine the theory of constructionism to effectively reflect the characteristic of WWW, and to build up a foundation of the web-based integrated e-learning circumstance. The circumstance is composed of 3 modules of the learner, instructor and the administrator. This aims to coordinate instruction functions in order to improve the effect of learning and to intensify the interaction. This paper presents the design and implementation of an e-learning system which is focused on the administrator's module to effectively support the operator's activity. As a result of this research, the system can be used in building up a variety of e-learning in university, that is, general training course and technical training course.

• Journal of The Korean Association For Science Education
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• v.18 no.4
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• pp.617-626
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• 1998

Inquiry approach in teaching science has been widespread in Korea since the Third National Curriculum in 1970's. But the effect of the approach has never been evaluated systematically in Korea, so the science educators do not know if the inquiry approach really works and if any critical problems inhibit the effect of the approach. In this context, the NAEP of the Unied States and the APU of the United Kingdom were model programs for assessing the effect of the inquiry approach in teaching science. The purpose of this study is to develop an assessment system for evaluating the effect of inquiry teaching in elementary and secandary schools. For this purpose, an assessment framework and 240 test items were developed and tried with a sample of 8,906 students. The results say that the developed tests are reliable. The average Cronbach $\alpha$ reliability coefficient of the tests was 0.69. The discrimination index(point-biserial correlation coefficient) ranged from 0.39 to 0.54 with a mean of 0.49, which indiate they are excellent in discriminating students in terms of their inquiry achievement. The test items were also analyzed by "item response theory." The results also say that the items are successfully developed.

• Journal of the Korea Society of Computer and Information
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• v.15 no.12
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• pp.237-245
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• 2010

Korea Communications Commission (KCC) has been providing the pilot service of URC(Ubiquitous Robot Companion), which is a network-based personal robot, to 1000 Korean households since 2006 to define potential users' needs and adoption behaviors. Personal innovativeness might play a critical role in adoption of URC services by users because much sophisticated and convergence technologies are incorporated into URC services. Also, defining not only perceived beliefs about URC services but also expected beliefs about them are very crucial to reduce disconfirmation between users' perception and expectation of URC services. From this point of view, this paper aimed to examine robot users' adoption behavior by considering constructs such as personal innovativeness, usefulness (perceived usefulness - expected usefulness, P-E), user attitude, and intention to use. The findings reveal that personal innovativeness is negatively related to usefulness (P-E) whereas usefulness (P-E) influences significantly and positively on user attitude. It is also shown that usefulness (P-E) and user attitude have strong positive effects on intention to use.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.2
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• pp.87-104
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• 2015

As the influence of Landscape Urbanism has grown, various criticisms on the discourse also have increased. A study on critical opinions of Landscape Urbanism is necessary to fully comprehend the theoretical structure of the discourse and its limitations. This study introduced the concept of Intension and Extension, which is used in the field of Logics and Semiotic, as an analytical tool to interpret various criticisms based on different views in a more objective and synthetic way. After examining the development of criticisms of Landscape Urbanism, 30 texts with important critiques on the theory were selected and analyzed. Criticisms can be classified as internal criticism and external criticism according to specific topics they are engaged with. The study only covers internal criticism as a research scope. The internal criticisms on Landscape Urbanism are re-categorized into topics of theory, practice and the relation between theory and practice. Vagueness of concepts and error in concepts are two types criticism related to the issue of theory. Lexical Ambiguity and Intensional Vagueness are the main causes of conceptual vagueness in Landscape Urbanism. Conceptual vagueness related with the problem of redefining an existing concept through expanding its meaning reveals a structural dilemma. There are three types of criticism included in the topic of practice: absence of practical results, form-oriented practice, and ambiguous identity in practical results. Ambiguous identity is caused by Extensional Vagueness allowing borderline cases. Because these borderline cases overlap with extensions of landscape architecture, it is hard to differentiate projects of Landscape Urbanism and those of conventional landscape architecture. Most criticisms on the relation between theory and practice raise the question on the practical method. Two types of criticism are engaged with the topic of the practical method: errors in practical methods and absence of practical methods. The absence of practical methods is a fundamental problem of Landscape Urbanism which is hard to solve by the proposed solutions. However, these structural problems are not only the weak point but also the factor that is able to prove the potentials expand the scope of Landscape Urbanism. In addition to the results of the study, internal criticisms on Landscape Urbanism should be examined in the following studies in order to predict the next direction of Landscape Urbanism.