• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.12
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• pp.1069-1078
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• 2013

In this paper, we propose a distributed time synchronization technique for OFDMA- based wireless mesh communication systems. The proposed technique employs the bio-inspired algorithm for self-time synchronization in the physical layer. To achieve the network synchronicity, the proposed technique updates the transmission time and the FFT window using the TDoA information of received signals from the neighbor nodes. The proposed technique can achieve fast self-synchronization among nodes with a simple algorithm, without the need of a centralized controller. The performance of the proposed time synchronization technique is evaluated by simulation in terms of convergence speed and convergence probability.

• The Journal of the Korea Contents Association
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• v.16 no.6
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• pp.236-247
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• 2016

Considering the prevalent use of mobile devices and the mobile Internet in Korea, there should be open doors for retailers to a different type of distribution if they could find out what makes consumers satisfied with m-commerce sites as well as what makes consumers purchase from m-commerce sites. Therefore, we explored: 1) the antecedents of satisfaction with m-commerce sites and 2) the determinants of purchasers vs. browsers of m-commerce. As possible antecedents of the two dependent variables, the following were utilized in the current study: the Technology Acceptance Model (TAM), perceived shopping values, and interactivity. According to the results of this study, these variables related to the performance of mobile commerce sites (Perceived ease of use, Perceived usefulness, Synchronicity, Richness of content, and Contextual services) significantly affected satisfaction with m-commerce sites. On the other hand, the most important discriminator of an m-commerce purchaser vs. a browser was human-oriented interactivity, especially interpersonal communication among users. With the help of information technology.

• Smart Structures and Systems
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• v.14 no.3
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• pp.469-477
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• 2014

As a kind of intelligent materials, conductive asphalt concrete has a broad application prospect including melting ice and snow on the pavement, closing cracks in asphalt concrete, sensing pavement damage, and so on. Conductive pavement will be suffered from fatigue failure as conventional pavement in the process of service, and this fatigue damage of internal structure can be induced by electrical signal output. The characteristics of electrical signal variation of conductive asphalt concrete in the process of fatigue cracking were researched in this paper. The whole process was clearly divided into three stages according to resistance changes, and the development of fatigue damage wasn't obvious in stage I and stage II, while in stage III, the synchronicity between the resistance and damage began to appear. Thus, fatigue damage variable D and initial damage value $D_0$ represented by the functions of resistance were introduced in stage III. After calculating the initial damage value $D_0$ under different stress levels, it was concluded that the initial damage value $D_0$ had no noticeable change, just ranged between 0.24 and 0.25. This value represented a critical point which could be used to inform the repair time of early fatigue damage in the conductive asphalt pavement.

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.285-288
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• 2005

If the motion is universal over the differences between the ancient age and the modern age, and between primitiveness and civilization, It is required to be studied, which make it possible to discover the universally valid interpreting elements of various societies and cultural phenomena. The study on the motion, as a base of universal motion study on animation and character modelling is considered as a very important part. The sampled motion prototype was classified by the continuity and the synchronicity that is a basis of modular analysis and of motion flow. Koguryo's mural paintings in old tombs has been the heritage and the symbol of the nation's historical identity and pride in Korean history. Koguryo is obviously a part of Korean history, which are of Korean elements. Accordingly, the mural paintings that this study has explicated is the origin as well as the history of Korean visual animation history, while the analysed and restored motion prototype is a module of Korean motion with golden section proportion.

• Korean Institute of Interior Design Journal
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• v.22 no.1
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• pp.115-123
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• 2013

Today, the views on Temporality of space have been changed not only to be based on the concept of time, but also to identify the space with a body adapted to the new circumstances. The study suggests that the actions of performers in space have been important by changes of views and are connected to the music phenomenology mixed with music whose tempo is the phenomenology related with of human consciousness itself, and derives the temporal property by putting them into Rem Koolhaas space with the fluid quality. According to Clifton's Phenomenology of Music, an understanding of music is made in both human body and consciousness as two ways to listen to sounds and enjoy music. Though a correlation between the characteristics of Clifton's Phenomenology of Music and one of resulted from uncertainty and immateriality of modern space Temporality, we could work out four kinds of characters which are the continuity of the fluidity from temporal programs, contrasting changes or synchronicity, the multidimensionality from synesthesia of line and face, ventilation by quality of the material and immaterial circumstances of sound effects, the implication in events resulted from cognition for information and unexpected actions, and the autonomy of the route of a variety of experiences including intimate connection of inter-related events and temporary and diverse external conditions. Hereby Temporality of musical phenomenology in Rem Koolhaas's space can be experienced by systems base oh the importance of host's motion, changes of programs according to the motion as well as uncertainty and immaterial changes. Due to the changes user's emotion and motion is undergone as Temporality that changes automatically.

• Journal of Fashion Business
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• v.24 no.4
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• pp.144-160
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• 2020

Today, the development of innovative technologies is accompanied by changes in the industrial structure and the Big Blur phenomenon, where the boundaries in various fields are blurred. The purpose of this study was to view the Big Blur phenomenon as a big paradigm shift in the 21st century and derive environmental changes and characteristics of the Korean fashion market. The research method included an analysis of the fashion brands after 2015. Through this study, we intended to establish a framework for understanding the changes in the fashion market from the perspective of Big Blur and discuss the direction of brand marketing. The research results showed the hyperlinks, connectivity, openness, homeostasis, synchronicity, mobility, interactivity, and brand experience of online and offline spaces beyond the boundaries of virtual space and offline physical spaces such as online physical and spatial viewpoints. It also showed the characteristics. The characteristics from the socio-cultural point of view were characteristic of diversity, mixture, coexistence, composability, and pluralism beyond the traditional socio-cultural and regulatory scopes. Hip hop fashion, street fashion, unisex, genderless, androgynous fashion, and kid fashion are the backbone of the Big Blur and are becoming important factors in fashion. The characteristics of the market and economic viewpoint are prosumers that play roles both as producers and consumers. It shows the extensibility of consumers as producers, the cohesiveness of producers and consumers, the cooperation, and the interconnectivity.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.9
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• pp.752-759
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• 2012

This paper presents a mission orbit design method for spacecraft which use the sun-synchronous and ground repeat orbits. In this work, we have proposed a new design procedure, "Nonlinear simulation-based numerical optimization technique" using the commercial S/W's such as STK (Satellite Tool kit) and Matlab, which are widely adopted S/W's in the area of orbital mechanics and engineering analysis. Inclusion of all the perturbation effects on the spacecraft not only can more precisely satisfy the mission requirements for sun-synchronicity and repeated ground track, and also operational requirements such as minimum change in the S/C local time, maximization of the contact time with a specified ground station, etc. can be appropriately considered. Design examples for LEO sun-synchronous mission are presented to demonstrate the usefulness of the proposed method in this paper.

• Ocean and Polar Research
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• v.41 no.3
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• pp.159-168
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• 2019

Understanding the interaction between climate and the water cycle is critical especially in a drought sensitive region such as California. This study explored hydrologic changes in central and southern California in relation to the glacial-interglacial climate cycles over the last 30 thousand years. To do this, we reconstructed paleovegetation using plant wax carbon isotopic compositions (${\delta}^{13}C$) preserved in marine sediment cores retrieved from the central California continental shelf (ODP Site 1018) and Santa Barbara Basin (ODP Site 893A). The results were then compared to the existing sea surface temperature (SST) and pollen records from the same cores to understand terrestrial hydrology in relation to oceanographic processes. The Last Glacial was generally dry both in central and southern California, indicated by grassland expansion, confirming the previously suggested notion that the westerly storm track that supplies the majority of the precipitation in California may not have moved southward during the glacial period. Southern California was drier than central California during the Last Glacial Maximum (LGM). This drying trend may have been associated with the weakening of the California Current and northerly winds leading to the early increase in SST in southern California and decline in both offshore and coastal upwelling. The climate was wetter during the Holocene in both regions compared to the glacial period and forest coverage increased accordingly. We attribute this wetter condition to the precipitation contribution increase from the tropics. Overall, we found a clear synchronicity between the terrestrial and marine environment which showed that the terrestrial vegetation composition in California is greatly affected by not only the global climate states but also regional oceanographic and atmospheric conditions that regulate the timing and amount of precipitation over California.

• Proceedings of the Korea Society of Design Studies Conference
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• 2004.05a
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• pp.44-45
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• 2004

With the development of informational machinery and tools in the modern industrial society, the image is expressed diversely as tools of informational transmission and artistic communication. This image is revival equipment and transmissional media in which sound and light are comprehensively formed. The image's intuitive and sensational expressivity can revive subjects and express a fiction, a reality, a nonfiction, and a virtual reality as a communication tool that has synchronicity and the medium of meaning. Because of this, the domain of the image will be gradually extended in the future, and the world of cognizance that can be detected across our living space will absorb the image diversely and react. In this context, the investigator examined what influence image media and equipments have in space as spatial equipments, based on the recognition of cerrelation among the image, space, and mankind, namely, the environmental meaning the mage and the space contain. Therefore, this study was conducted from the aspects of relationship establishment between image equipments that are ever expansive to a variety of domains and the space that accommodates the equipments. As study findings, the influences the image equipments have on space and their expressional features are presented in three aspects: 'the expressional medium of mutual synergy','metaphysical ultra-epithelial space constituent',' and 'object'. This study seems to be meaningful in that we can expect the spatial approach method by purposes and spatial layout of image structures, with this study, through analyzing the meaning of relationship between image equipments and space.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.6
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• pp.27-37
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• 2016

Startup teams should be prompt to seize an business opportunity and handle various business problems with which they has not been faced before. This research examines and compares the hypotheses about the processes of communication media usage, knowledge sharing and team agility by the level of task conflict. In order for detailed investigation, each of antecedent was divided into sub-dimensions: communication media usage into synchronous and asynchronous media usage, and knowledge sharing into speed and quantity of knowledge sharing. Team agility, the dependent variable, was proposed as an important success factor of startup teams. The research model describes that the communication media usage affects knowledge sharing and consequently team agility. The differences of media usage and relationships among variables were proposed as the level of task conflict in teams. 230 data points were collected from startup teams under 5 years and statistically processed to test research model and hypotheses. From the total sample analysis, the results indicate that the knowledge sharing speed is positively associated with the quantity, and the knowledge sharing speed and quantity have positive associations with team agility. Both synchronous and asynchronous communication media usage also has significant positive associations with knowledge sharing speed. On the other hand, media usage did not show significant direct association with knowledge sharing quantity. From the group comparisons of task conflict, it was found that the higher task conflict, the higher in media usage, knowledge sharing speed and quantity, and team agility. The process of media usage, knowledge sharing, and team agility were found to be different between the high and low task conflict. From these results, the authors discussed and proposed some implications for startup team leaders.