• International Journal of Railway
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• v.2 no.2
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• pp.43-49
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• 2009

Wear and rolling contact fatigue (RCF) defects are most important causes of rail damage, and often interaction competitive at present railway track. Head check is one of rolling contact fatigue (RCF) defects, and generally occurs in mild circular curves and transition curves that are set at both ends of sharp circular curves. Wear tends to limit the crack growth of head checks by removing the material from the RCF surface. In order to clarify the conditions of the occurrence and growth of head checks, the authors measured the interacting forces between wheels and rails and the angle of attack of wheelset, and carried out contact analyses using the actual profile data of wheels and rails. The effects of the lateral force, the contact geometry, and the wear rate at rail gauge comer on the formation of head checks were also analyzed by using the worn profiles of actual wheels and rails and the data obtained by a track inspection car. Some specific range of wear rate at the gauge comer was identified as having close relation with occurrence of head checks.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2007.05a
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• pp.101-110
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• 2007

Current strategic trends in service distribution and software development in response to Web as a platform represent a paradoxical concurrent pursuit of 'economy of scale' and 'service'. From the software perspective, the major novel elements of the Web 2.0 era are Web as a platform and the emergence of long-tail service enabling web sites to function as an independent distribution channel. The current study analyzed the platform strategy for establishing a community of interactive developer and customers taking the issue of economy of scale into consideration. Software industry should face the new reality and utilize the open source community for cost minimization and securing customer base. Furthermore, Lego-style software development should be adopted for maintaining cost-competitiveness in customized software development.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.27.2-27.2
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• 2010

We report the HST pixel analysis results of the interacting face-on spiral galaxy, NGC 5194 (M51), which is the first step of a new observational research project, PANCluG (Pixel Analysis of Nearby Cluster Galaxies). We derive several quantities describing the pixel color-magnitude diagram (pCMD) of NGC 5194, suitable for future comparisons with the pCMDs of other galaxies. We investigate the spatial distribution of pixel stellar populations, finding that the spiral arm pattern and the tidal interaction with NGC 5195 significantly affect the stellar populations in NGC 5194. We find that the pixels corresponding to the central active galactic nucleus (AGN) of NGC 5194 show a very tight sequence in the bright-end of the pCMD, of which spatial distribution seems to agree with the AGN torus region.

• International Journal of Advanced Culture Technology
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• v.5 no.1
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• pp.51-57
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• 2017

Digital signage is becoming part of daily life across a wide range of visual advertisements segments market used in stations, hotels, retail stores, hotels, etc. The current digital signage system used in market is generally works on limited user interactivity with static contents. In this paper, a new approach is proposed using computer vision based dynamic audience adaptive cost-effective digital signage system. The proposed design uses the Camera attached Raspberry Pi Open source platform to employ the real-time audience interaction using computer vision algorithms to extract facial features of the audience. The real-time facial features are extracted using Haar Cascade algorithm which are used for audience gender specific rendering of dynamic digital signage content. The audience facial characterization using Haar Cascade is evaluated on the FERET database with 95% accuracy for gender classification. The proposed system, developed and evaluated with male and female audiences in real-life environments camera embedded raspberry pi with good level of accuracy.

• Earthquakes and Structures
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• v.3 no.3_4
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• pp.533-548
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• 2012

Dynamic analysis of concrete gravity dam-reservoir systems is an important topic in the study of fluid-structure interaction problems. It is well-known that the rigorous approach for solving this problem relies heavily on employing a two-dimensional semi-infinite fluid element. The hyper-element is formulated in frequency domain and its application in this field has led to many especial purpose programs which were demanding from programming point of view. In this study, a technique is proposed for dynamic analysis of dam-reservoir systems in the context of pure finite element programming which is referred to as the wavenumber approach. In this technique, the wavenumber condition is imposed on the truncation boundary or the upstream face of the near-field water domain. The method is initially described. Subsequently, the response of an idealized triangular dam-reservoir system is obtained by this approach, and the results are compared against the exact response. Based on this investigation, it is concluded that this approach can be envisaged as a great substitute for the rigorous type of analysis.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.39 no.3
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• pp.62-78
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• 2002

In this paper, we describe a system that can interact with agents in the virtual space incorporated in the system. This system is constructed by an analysis system for analyzing human gesture and an interact system for interacting with agents in the virtual space using analyzed information. An implemented analysis system for analyzing gesture extracts a head and hands region after taking image sequence of an operator's continuous behavior using CCD cameras. In interact system, we construct the virtual space that exist an avatar which incarnating operator himself, an autonomous object (like a Puppy), and non-autonomous objects which are table, door, window and object. Recognized gesture is transmitted to the avatar in the virtual space, then transit to next state based on state transition diagram. State transition diagram is represented in a graph in which each state represented as node and connect with link. In the virtual space, the agent link an avatar can open and close a window and a door, grab or move an object like a ball, order a puppy to do and respond to the Puppy's behavior as does the puppy.

• Journal of The Korean Association For Science Education
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• v.41 no.5
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• pp.415-428
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• 2021

The COVID-19 pandemic has changed everything, even education. Last year when distance learning was introduced, science teachers faced many challenges to overcome. However, teachers adapted quickly, and in this year, it became the 'new normal'. In this situation, teachers are likely to habitually repeat past practices, but the context of the second year of distance learning is changing constantly, and teachers are asked to interpret the problem occurring in a situation and to adjust their practice for solving the problem with their teacher agency. In this study, we explore the emergence of science teacher agency and factors shaping teacher agency in the second year of distance learning and we focus on teachers' agentic practice that did not follow their past practice without reflection. For this purpose, we mainly analyze the semi-constructed interview of three science teachers. In the first year of distance learning, two teachers maintained their practice, not much different to face-to-face learning. However, one teacher reflected upon herself and started to recognize and solve her problems. Reflection for her practice can support this process. Another teacher changed her practice due to external suggestions, but it evolved her practice to fit the situation better, and her experience of last year helped her to adapt to the change. The other teacher who modified her practice to persist her professional purpose last year was consistently practicing in the second year and collaboration and autonomy can support her. This study shows the teachers' dynamic change of agency and the emergence for the relational interaction between teacher and context.

• The Journal of Sustainable Design and Educational Environment Research
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• v.23 no.3
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• pp.1-13
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• 2024

This study aims to identify users' perceptions and needs to improve college teaching spaces in nursing education, and thus derive improvement measures. Therefore, group interviews (three to five participants per category) were conducted with professors (7), students (9), and administrative staff (8) at a college of nursing located in Seoul. All interviews were conducted face-to-face, with each interview taking approximately 60-90 min. The interview results were analyzed for professors, students, and administrative staff separately. The following implications were drawn by synthesizing the interview results for each group: (1) the physical environment and quality of interaction between professors and students need to be improved in order to enhance the quality of teaching and learning; (2) a well-designed practice environment that allows students to practice various skills with confidence needs to be provided; (3) classrooms need to be configured and arranged in a way that is appropriate the nursing curriculum and educational activities to maximize learning effectiveness; (4) spatial restructuring is necessary in terms of living and resting spaces to help nursing students manage stress and provide them with psychological stability; and (5) administrative support reflecting the nursing curriculum is needed in establishing classroom assignment criteria and space use regulations. Finally, the limitations of this study and suggestions for further research were discussed.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.1
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• pp.123-132
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• 1999

One of the major difficulties in the seismic analysis of a dam-reservoir system is the treatment of the energy radiation in the upstream direction of the reservoir. In the paper, a new transmitting boundary is presented that can model properly the radiation of energy in the far field direction of a semi-infinite reservoir with constant depth. In the newly developed method, effects of surface wave motion are taken into accounted and the reservoir-foundation interaction is approximately accounted for with an absorbing boundary condition. If a dam has vertical upstream face and the infinitely long reservoir maintains constant depth, then the proposed transmitting boundary can be directly coupled with the model of dam body. In present study, the dam body is assumed to behave elastically and modeled by finite element method. Seismic responses of a dam model are investigated using the newly developed transmitting boundary.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.8
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• pp.1297-1309
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• 2007

The purpose of this study is to investigate the effect of shirt color, tie color, tone, perceiver' gender on impression formation by applying tone-in-tone coloration of shirt and necktie: coloration of two colors. This experiment was designed to utilize the $2{\times}6{\times}4{\times}2$ factorial designs. and they are shirt color(red, blue), tie color(red, yellow red, yellow, green, blue, purple), tone(vivid, light, dull, dark), and perceiver' gender(a male, a female). The experimental materials developed for this study were a set of stimulus and response scales. The stimuli were 48 upper body photographs which were color outputs by CAD system(4D-box program). The subjects of this research were 288 male and 288 female college students. There were established impression dimension from factor analysis 27 bi-polar adjectives and investigated the effect of interaction between each variable affected impression formations. The items of the adjectives are classified into 4 Impression dimensions: activity, potency, attractiveness, and tenderness. Shirt color, tie color, tone, and perceiver' gender influenced on impression formation. Specially, tie color and tone influenced on the 4 impression dimension greatly by interaction as well as independently. As a result tie is very important clue of impression formation in tone-in-tone coloration of shirt and necktie. Even though tie occupies only a small area in men's clothes it has great effect since it is close to the face.