• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.3
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• pp.245-251
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• 2014

As delineating market areas of retail businesses has become an interesting topic in marketing field, Lee and Lee recently suggested a noteworthy method, which applied the hydrological analysis of geographical information system (GIS), based on Christaller's central place theory. They used a digital elevation model (DEM) which inverted the kernel density of retail businesses, which was measured by using bandwidths of pre-determined 500, 1000 and 5000 m, respectively. In fact, their method is not a fully data-based approach in that they used pre-determined kernel bandwidths, however, this paper has been planned to improve Lee and Lee's method by using a kind of data-based approach of the L-index that describes clustering level of point feature distribution. The case study is implemented to automobile-related retail businesses in Seoul, Korea with selected Kernel bandwidths, 1211.5, 2120.2 and 7067.2 m from L-index analysis. Subsequently, the kernel density is measured, the density DEM is created by inverting it, and boundaries of market areas are extracted. Following the study, analysis results are summarized as follows. Firstly, the L-index can be a useful tool to complement the Lee and Lee's market area analysis method. At next, the kernel bandwidths, pre-determined by Lee and Lee, cannot be uniformly applied to all kinds of retail businesses. Lastly, the L-index method can be useful for analyzing the space structure of market areas of retail businesses, based on Christaller's central place theory.

• International Journal of Aeronautical and Space Sciences
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• v.12 no.4
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• pp.305-317
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• 2011

This paper presents an overview on flutter boundary prediction in tests which is principally based on a system stability measure, named Jury's stability criterion, defined in the discrete-time domain, accompanied with the use of autoregressive moving-average (AR-MA) representation of a sampled sequence of wing responses excited by continuous air turbulences. Stability parameters applicable to two-, three- and multi-mode systems, that is, the flutter margin for discrete-time systems derived from Jury's criterion are also described. Actual applications of these measures to flutter tests performed in subsonic, transonic and supersonic wind tunnels, not only stationary flutter tests but also a nonstationary one in which the dynamic pressure increased in a fixed rate, are presented. An extension of the concept of nonstationary process approach to an analysis of flutter prediction of a morphing wing for which the instability takes place during the process of structural morphing will also be mentioned. Another extension of analytical approach to a multi-mode aeroelastic system is presented, too. Comparisons between the prediction based on the digital techniques mentioned above and the traditional damping method are given. A future possible application of the system stability approach to flight test will be finally discussed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.2
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• pp.769-786
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• 2016

Object recognition and object location have always drawn much interest. Also, recently various computational models have been designed. One of the big issues in this domain is the lack of an appropriate model for extracting important part of the picture and estimating the object place in the same environments that caused low accuracy. To solve this problem, a new Salient Based Bag of Visual Word (SBBoVW) model for object recognition and object location estimation is presented. Contributions lied in the present study are two-fold. One is to introduce a new approach, which is a Salient Based Bag of Visual Word model (SBBoVW) to recognize difficult objects that have had low accuracy in previous methods. This method integrates SIFT features of the original and salient parts of pictures and fuses them together to generate better codebooks using bag of visual word method. The second contribution is to introduce a new algorithm for finding object place based on the salient map automatically. The performance evaluation on several data sets proves that the new approach outperforms other state-of-the-arts.

• Journal of Astronomy and Space Sciences
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• v.27 no.4
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• pp.359-366
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• 2010

In this study, we developed a global ionosphere model based on measurements from a worldwide network of global positioning system (GPS). The total number of the international GPS reference stations for development of ionospheric model is about 100 and the spherical harmonic expansion approach as a mathematical method was used. In order to produce the ionospheric total electron content (TEC) based on grid form, we defined spatial resolution of 2.0 degree and 5.0 degree in latitude and longitude, respectively. Two-dimensional TEC maps were constructed within the interval of one hour, and have a high temporal resolution compared to global ionosphere maps which are produced by several analysis centers. As a result, we could detect the sudden increase of TEC by processing GPS observables on 29 October, 2003 when the massive solar flare took place.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.3
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• pp.129-140
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• 2017

This study aims to interpret the current landscape design of the place and landscape of memory, such as post-industrial parks and memorials that have an old, aging appearance from an aesthetic perspective. The objects of the study are large parks and open spaces that have collective memories for visitors. Visitors' aesthetic experience from these places and landscapes of memory could be explained by aesthetic concepts such as the sublime, nostalgia, and melancholy. Because these aesthetic concepts are associated with past traumas, visitors may be affected morbidly. However, due to the capability of the media to form an aesthetic experience when visitors visit a given place and landscape, visitors can autonomously adjust the distance to the place of memory and gain an aesthetic experience. The aesthetic experiences through the sublime, nostalgia, and melancholy are based on temporality and irreversibility. Temporality here refers to a characteristic of memory, and time in the place and landscape of memory and is based on the irreversibility of time, as time cannot go back. Both the place memory and the memory that is recalled from the combination with visitor's past memories and knowledge are two major factors involved in the construction of the aesthetic experience in the place and landscape of memory. The results of the present study are meaningful in that this study presents a framework for a better understanding and use of both the place memory and appreciators' memory in the design process of a place and landscape of memory and also criticizes a materialistic approach that fails to take into account the visitors' memories.

• International Journal of Knowledge Content Development & Technology
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• v.13 no.1
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• pp.59-74
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• 2023

Third places are those that offer a space outside of work and home for people to escape the stress associated with the primary spaces of their lives. Through social interactivity these help in acquiring some emotional support provided by a close and intimate attachment. Such social support can turn into social resources for individuals and can lead to forming communities that may become incubators for social capital through regular visits to shared socializing places. This paper focuses on social interaction that takes place through the third place and the communities that are being created as a contributing factor to knowledge management. The study being reported in this paper investigated the role of coffee shops as third places in building communities and social capital in Kuwait. A mixed-method approach was used to conduct the study. These methods included qualitative methods such as extended conversations in the form of semi-structured interviews and quantitative methods of using questionnaires distributed to coffee shop staff and visitors. Results indicated that importance attached to providing facilities by coffee shops reflected that the owners perceived these as third places. The facilities attracted customers to coffee houses where interactions took place that helped to build communities. The pattern of visits by customers showed that mostly they come in groups and have meetings and gatherings that facilitated and encouraged interactions. The communities that are being built in the coffee shops are indicative of these being perceived as third places by owners, customers, and staff. This study shows the potential of coffee shops as a major sector of the food industry promising a valuable contribution in transformation and transition to a knowl- edge-based economy in Kuwait.

• Journal of Korean Society of Transportation
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• v.26 no.5
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• pp.163-174
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• 2008

The conventional four-step travel demand model is still widely used as the state-of-practice in most transportation planning agencies even though it does not provide reliable estimates of travel demand. In order to improve the accuracy of travel demand estimation, implementing an alternative approach would be critical as much as acquiring reliable socioeconomic and travel data. Recently, the role of travel demand model is diverse to satisfy the needs of microscopic analysis regarding various policies of travel demand management and traffic operations. In this context, the activity-based approach for travel demand estimation is introduced and a case study of developing a spatial-temporal activity presence-based approach that estimates travel demand through forecasting number of people present at certain place and time is accomplished. Results show that the spatial-temporal activity presence-based approach provides reliable estimates of both number of people present and trips actually people made. It is expected that the proposed approach will provide better estimates and be used in not only long-term transport plans but short-term transport impact studies with respect to various transport policies. Finally, in order to introduce the spatial-temporal activity presence-based approach, the data such as activity-based travel diary and land use based on geographic information system are essential.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.16 no.1
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• pp.103-108
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• 1987

The heat transfer processes taking place in the side wall of a thermocline enclosure have been analyzed for idealized conditions based on the assumption that, at any instant time, side wall heat transfer processses are independent of the thermocline bulk motion. However, the axial tempera-ture distribution in the thermocline core provides the means for specifying the liquid medium-side boundary condition to the enclosure side wall. A picture is drawn which reflects the side wan response to thermocline bulk motion within the frame work of a quasi-steady analytic approach. For valves of the parameters typical of systems of engineering interest, the analysis shows that a significant amount of heat transfer short - circuiting can take place along the side wall enclosure. This phenomenon is favored by high values of $H_l$ and low values of P and $H_g$ respec-tively. The location of the point of zero normal heat flux on the side wan can be expected to mark, approximately, the region of confluence of two sidewall boundary flows respectively driven by the buoyant effects.

• Proceedings of the IEEK Conference
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• summer
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• pp.70-73
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• 2004

We have developed an optimization algorithm based formulation for performing efficient time driven simultaneous place and route for FPGAs. Field programmable gate array (FPGAs) provide of drastically reducing the turn-around time for digital ICs, with a relatively small degradation in performance. For a variety of application specific integrated circuit application, where time-to-market is most critical and the performance requirement do not mandate a custom or semicustom approach, FPGAs are an increasingly popular alternative. This has prompted a substantial amount of specialized synthesis and layout research focused on maximizing density, minimizing delay, and minimizing design time.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04c
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• pp.283-285
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• 2003

We have developed an optimization algorithm based formulation for performing efficient time driven simultaneous place and route for FPGAS. Field programmable gate array(FPGAS) provide of drastically reducing the turn-around time for digital ICs, with a relatively small degradation in performance. For a variety of application specific Integrated circuit application, where time-to-market is most critical and the performance requirement do not mandate a custom or semicustom approach, FPGAS are an increasingly popular alternative. This has prompted a substantial amount of specialized synthesis and layout research focused on maximizing density, minimizing delay, and minimizing design time.