• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.6
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• pp.95-104
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• 2015

Recently, collecting and analyzing method of users location has been studied due to the development of mobile devices. There is analyzing method using Semantic Location History in order to identify of characteristics and extract pattern and predict trajectory of users. We should extraction of Stay Point in order to use Semantic Location History. The Conventional extraction method of Stay Point is not accuracy of location of Stay Points because it does not specify the GPS log of users. Also, Conventional extraction method of Stay Point cannot distinguish indoors and outdoors. In this paper, we implement extraction method of Stay Point in which specify the GPS log of users and extraction of Stay Point at indoors only. Stay Point(nearSP) specifies the nearest GPS log of users from generated Stay Point by conventional extraction method. And, Stay Point(indoorSP) specifies the GPS log of users that user get into the building. Our experimental results, accuracy of Stay Point is improved, and capacity of output data decrease than Conventional extraction method. Also, we were able to distinguish Stay Point of indoors and outdoors.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.2
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• pp.40-47
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• 2009

This paper proposes a method for vehicle license plate detection using mathematical morphology and symmetry. In general, the shape, color, size, and position of license plate are regulated by authorities for a better recognition by human. Among them, the relatively big intensity difference between the letter and the background region of the license plate and the symmetry about the plate are major discriminating factors for the detection. For the first, the opened image is subtracted from the closed image to intensify the region of plate using the rectangular structuring element which has the width of the distance between two characters. Second the subtraction image is average filtered with the mask size of the plate. Third, the column maximum graph of the average filtered image is acquired and the symmetry of the graph is measured at every position. Fourth, the peaks of the average filtered image are searched. Finally, the plate is assumed to be positioned around the one of local maxima nearest to the point of the highest symmetry. About 1,000 images taken by speed regulation camera are used for the experiment. The experimental result shows that the plate detection rate is about 93%.

• Journal of the Korean Society for Railway
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• v.20 no.4
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• pp.521-528
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• 2017

In this study, vertical loading tests were conducted to investigate the nonlinear behaviors of the fastening systems that have generally been used in the concrete track of domestic railway lines. Nonlinear load-displacement curve models were derived based on the test results. The uplift forces generated in the fastening systems were evaluated by applying the derived nonlinear models as well as the existing linear models. The influence of the factors on the maximum uplift force of the fastening system was analyzed through a parameter study on the distance between neighboring sleepers, the horizontal distance between the center of the bearing and the nearest fastening system from the deck end, and the height of the bridge girder. From the evaluation results it is known that, for economical track and bridge design, due to deck end deformation, it is necessary to consider the nonlinear behavior of the fastening system in the calculation of the uplift force of the fastening systems.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.590-592
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• 2018

Taxis that are illegally parked on the road to catch customer can cause traffic congestion and sometimes cause traffic accidents. Stop position of taxis is determined by the long term experience of taxi drivers. In this study, We provide information to taxi drivers and customer who visit in first time through finding stop position of taxis by time. To do this, we used the Internet of Vehicle (IoV) data collected from sensors installed in 40 taxis. Previous studies attempted by forming a cluster around a taxi. Since this method is centered on a taxi, the position of the cluster changes depending on the location of the taxi. In this study, we use a road segmentation algorithm to solve these problems. Unlike the previous studies, since the cluster is formed around the road, the position of the cluster is fixed and it is not affected by the number of taxis, so it is possible to grasp the stop position in real time. The road segmentation is made up of 30m units, and map the taxi location data divided into hourly, weekday, and weekend to the nearest point. As a result of the mapping, it was difficult to see a big difference in the time of week because there were few taxis to operate on weekends, but in case of weekdays, the difference of stop position between the commute time zone and the night time zone was confirmed. The results of this study suggest that it will be possible to propose the prevention of taxi illegally driving taxi and the location of the taxi stand.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.8
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• pp.535-542
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• 2013

Since case-based reasoning(CBR) has many advantages, it has been used for supporting decision making in various areas including medical checkup, production planning, customer classification, and so on. However, there are several factors to be set by heuristics when designing effective CBR systems. Among these factors, this study addresses the issue of selecting appropriate neighbors in case retrieval step. As the criterion for selecting appropriate neighbors, conventional studies have used the preset number of neighbors to combine(i.e. k of k-nearest neighbor), or the relative portion of the maximum similarity. However, this study proposes to use the absolute similarity threshold varying from 0 to 1, as the criterion for selecting appropriate neighbors to combine. In this case, too small similarity threshold value may make the model rarely produce the solution. To avoid this, we propose to adopt the coverage, which implies the ratio of the cases in which solutions are produced over the total number of the training cases, and to set it as the constraint when optimizing the similarity threshold. To validate the usefulness of the proposed model, we applied it to a real-world target marketing case of an online shopping mall in Korea. As a result, we found that the proposed model might significantly improve the performance of CBR.

• Computers and Concrete
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• v.3 no.5
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• pp.301-312
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• 2006

Experimental research revealed that the spatial dispersion of aggregate grains exerts pronounced influences on the mechanical and durability properties of concrete. Therefore, insight into this phenomenon is of paramount importance. Experimental approaches do not provide direct access to three-dimensional spacing information in concrete, however. Contrarily, simulation approaches are mostly deficient in generating packing systems of aggregate grains with sufficient density. This paper therefore employs a dynamic simulation system (with the acronym SPACE), allowing the generation of dense random packing of grains, representative for concrete aggregates. This paper studies by means of SPACE packing structures of aggregates with a Fuller type of size distribution, generally accepted as a suitable approximation for actual aggregate systems. Mean free spacing $\bar{\lambda}$, mean nearest neighbour distance (NND) between grain centres $\bar{\Delta}_3$, and the probability density function of ${\Delta}_3$ are used to characterize the spatial dispersion of aggregate grains in model concretes. Influences on these spacing parameters are studied of volume fraction and the size range of aggregate grains. The values of these descriptors are estimated by means of stereological tools, whereupon the calculation results are compared with measurements. The simulation results indicate that the size range of aggregate grains has a more pronounced influence on the spacing parameters than exerted by the volume fraction of aggregate. At relatively high volume density of aggregates, as met in the present cases, theoretical and experimental values are found quite similar. The mean free spacing is known to be independent of the actual dispersion characteristics (Underwood 1968); it is a structural parameter governed by material composition. Moreover, scatter of the mean free spacing among the serial sections of the model concrete in the simulation study is relatively small, demonstrating the sample size to be representative for composition homogeneity of aggregate grains. The distribution of ${\Delta}_3$ observed in this study is markedly skew, indicating a concentration of relatively small values of ${\Delta}_3$. The estimate of the size of the representative volume element (RVE) for configuration homogeneity based on NND exceeds by one order of magnitude the estimate for structure-insensitive properties. This is in accordance with predictions of Brown (1965) for composition and configuration homogeneity (corresponding to structure-insensitive and structure-sensitive properties) of conglomerates.

• Journal of the Korea Society for Simulation
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• v.25 no.1
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• pp.53-61
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• 2016

This paper introduces 'EgresSIM', which is microscopic evacuation simulation software. EgresSIM developed in this paper is a three-dimensional (3D) pedestrian evacuation simulator based on the improved model advanced from the floor field model(FFM), a microscopic pedestrian model. This software can simulate large size buildings that consist of a number of floors, stairs, rooms, and exit doors. Moreover, this software can arrange several hundreds or thousands of pedestrians in indoor space and check their movements through the 3D viewer in real time, as well as produce detailed results about evacuation situations such as which paths are employed by individual pedestrians, how long does it takes to evacuate, and how many evacuees are gathered at each of the exit doors. Building data needed in the simulation are constructed as XML files according to pre-defined indoor data models and information of simulation results is also created as XML log files. A moving pattern of pedestrians can be represented in many ways by adjusting the sensitivity parameters of two walk models supported by EgresSIM. Thus, evacuation simulation can be done based on many assumptions of situations such as movement to the nearest exit door or blackout after outage.

• Korean Journal of Plant Resources
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• v.28 no.1
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• pp.26-34
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• 2015

This study was conducted to examine the morphological characteristics and variations of the 6 populations of Pourthiaea. villosa (Thunb.) Decne. var. villosa in Korea. The ANOVA results showed that the populations were significantly different in 18 of the 21 quantitative characteristics that were analyzed. In the results of principal component analysis, 6 principal components (PC) represented 68.28% for the total variations. 'Petiole length' (0.764), 'Leaf shape' (0.834), 'Leaf length' (0.753), 'Crown diameter' (0.663), 'Inflorescence width' (0.492), and 'Leaf base shape' (0.721) showed the highest contribution to PC1, PC2, PC3, PC4, PC5, and PC6, respectively. According to the results of cluster analysis, one cluster comprised only 'Goesan-gun Ssanggok Valley' population. 'Namhae-gun Mijori Evergreen Forest' population was grouped with 'Hamyang-gun Sang Forest' population, which was the nearest subgroup. Further, 'Namhae-gun Geum Mountain' population, 'Jindo-gun Cheomchal Mountain' population, and 'Jeju-si Barimae Parasitic volcano' population were placed in the same cluster.

• Journal of Oral Medicine and Pain
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• v.30 no.1
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• pp.121-129
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• 2005

In this experiment, eleven volunteers were followed up for 15 months after the injection of botulinum toxin type A on right and left masseter muscles. The measurement of masseter muscle atrophy for each volunteer was performed by CT(computed tomography) three times: before the injection, three and fifteen months after the injection. The thickness and area of muscle were measured in three positions which are 10 (position 1), 20 (position 2), and 40 mm (position 3) above the inferior border of mandible(the injection site was nearest the position 1). The thickness of masster muscle was decreased in all three positions three months after the injection, but no significant change was observed fifteen months after the injection. On the other hand, the area of masster muscle was decreased in all three positions three months after the injection. Furthermore, the area was decreased significantly in positions 1 and 2, but not in position 3 fifteen months after the injection. As a result, toxin is still in effect even fifteen months after the injection. Finally, the present study shows that the measurement of muscle area provides more precise informations than that of muscle thickness does.

• Korean Journal of Environment and Ecology
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• v.16 no.3
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• pp.271-286
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• 2002

To understand the status of vegetational composition of Jungnangcheon, 21 plots in 7 sites were investigated in June 2001 and flora survey was done during the period from June to September 2001. The results obtained from this study were as follows: Vegetational compositions of 7 sites in Jungnangcheon area were different site by site and plot by plot. In lower(nearest) point, Phalaris arundinacea, Potentilla supina, Rorippa islandica, Chenopodium album, Beckmannia syzigachne and Chenopodium ficifolium showed higher constancy and frequency. Bromus japonicus, Humulus japonicus, Conyza canadensis, Elymus tsukusiensis var. transiens showed higher constancy and frequency in middle point and Bromus japonicus, Chenopodium ficifolium, Artemisia princeps var. orientalis showed in upper point. Bromus japonicus, Chenopodium ficifolium, Humulus japonicus, Conyza canadensis, Elymus tsukusiensis var. transiens, Artemisia princeps var. orientalis and Lepidium uirginicum appeared at more than 9 polts in 21 sample plots. Number of naturalized plants in Jungnangcheon area were 79 taxa. Total naturalized index(NI) and urbanized index(UI) were recorded as 29.2%, 27.9%. 253 taxa including 50 families 169 genera 224 species 1 subspecies 27 varieties 1 forma were recorded in Jungnangcheon area. Therophyte(Th) was the most common dormancy form recorded in survey area. Geophyte(G) and Hemicryptophyte(H) were calculated as 7.1%, 17.8% and it was the lower value compared to those of other dormancy form. Consequently, Th-R$_{5}$-D$_4$-e was recorded as the most common life form in Jungnangcheon.