• Journal of IKEEE
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• v.25 no.4
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• pp.756-761
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• 2021

Dynamic route guidance (DRG) finds the fastest path from a source to a destination location considering the real-time congestion information. In Korea, the traffic state information is available by the public transportation data (PTD) which is indexed on top of the node-link map (NLM). While the NLM is the authoritative low-detailed road network for major roads only, the OpenStreetMap road network (ORN) supports not only a high-detailed road network but also a few open-source routing engines, such as OSRM and Valhalla. In this paper, we propose a DRG framework based on road network matching between the NLM and ORN. This framework regularly retrieves the NLM-indexed PTD to construct a historical speed profile which is then mapped to ORN. Next, we extend the Valhalla routing engine to support dynamic routing based on the historical speed profile. The numerical results at the Yeoui-do island with collected 11-month PTD show that our DRG framework reduces the travel time up to 15.24 % and improves the estimation accuracy of travel time more than 5 times.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.108-118
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• 2014

The purpose of this study is to develop a relationship of measuring method for the social security network and verify its validity and reliability and apply it to investigate the due to security life satisfaction. This study is based by setting general residents of Seoul in 2013 and using the stratified cluster random sampling method to analyze a total amount of 203 examples. The measuring methods for the social security network was developed through document research, conceptual definition and drafting the survey, experts' conference, preliminary inspection and original examination, verification of the validity and reliability of the survey. An experts' conference took pace to verify the validity of the survey, and 6 factors were extracted through exploratory factor analysis crime prevention design, street CCTV facilities, volunteer neighborhood patrol, local government security education, police public peace service, private security service. The conclusion are the following. Collected data was analyzed based on the aim of this study using SPSSWIN 18.0, and practice frequency analysis, F test, factor analysis, reliability analysis, correlation analysis, multiple regression analysis. First, the validity of the social security network measurement is very high. Thus, the factors constituting the social security network were found to be crime prevention design, street CCTV facilities, volunteer neighborhood patrol, local government security education, police public peace services, and private security services, and the crime prevention design factor was found to be most explanatory. Second, the reliability of the social security network measurement is very high. Thus, the correlation between the questions and the sector, the questions and the social security net was very high, and the internal consistency showed a Cronbach's${\alpha}$ value of over 0.865. Third, the establishment of a social security network had the biggest effect on people in their forties. Thus, when the crime prevention design, street CCTV facilities, local government security education, police public peace services are systematically established, the social anxiety of citizens was reduced.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.1
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• pp.61-71
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• 2007

The main purpose of this study was to develop Automatic Measurement System for monitoring tree's vigor using Ubiquitous Sensor Network This study also focused on presenting an alternative for monitoring automatically tree's vigor due to Shigometer's limits. Application test of the system in comparison with Shigometer showed that the measurement values were not different to choose between the two, and battery lasted about 1,844 days in this system. To test the sensor network the possible transmission distance using the sensor network in maximum was 130m. Investigation and management expenses can be reduced and labor productivity will also be improved in the forest and street trees.

• Phonetics and Speech Sciences
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• v.13 no.1
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• pp.45-51
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• 2021

End-to-end (E2E) automatic speech recognition (ASR) has achieved promising performance gains with the introduced self-attention network, Transformer. However, due to training time and the number of hyperparameters, finding the optimal hyperparameter set is computationally expensive. This paper investigates the impact of hyperparameters in the Transformer network to answer two questions: which hyperparameter plays a critical role in the task performance and training speed. The Transformer network for training has two encoder and decoder networks combined with Connectionist Temporal Classification (CTC). We have trained the model with Wall Street Journal (WSJ) SI-284 and tested on devl93 and eval92. Seventeen hyperparameters were selected from the ESPnet training configuration, and varying ranges of values were used for experiments. The result shows that "num blocks" and "linear units" hyperparameters in the encoder and decoder networks reduce Word Error Rate (WER) significantly. However, performance gain is more prominent when they are altered in the encoder network. Training duration also linearly increased as "num blocks" and "linear units" hyperparameters' values grow. Based on the experimental results, we collected the optimal values from each hyperparameter and reduced the WER up to 2.9/1.9 from dev93 and eval93 respectively.

• Journal of Korean Society of Transportation
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• v.26 no.3
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• pp.129-141
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• 2008

Portable navigation markets grew up to 95% last year. This study aims to develop a business model for pedestrian-oriented portable navigator for street shoppers. Related previous studies developed successfully the alogrithm for a portable navigator, and the current study seeks for diverse ways to turn this system into a new type of on & off line-based LBS business. The business model proposed in this study adopted two different approaches of benefit yields based on the structural analysis of so-called Wanavi navigation system. One is segmented approach seeking for benefits from each individual system component such as communication network, contents, and platform. The other approach is to run the business by integrating relevant system componts in every possible way to attract customers to this portable navigator. The purpose of this proposal is not limited to activate emerging walking navigator markets, but to aim at creating idealistic free market system where all the shoppers are furnished complete market information to the fullest extent when they go on shopping.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.127-130
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• 2005

Internal cities such as gray level been enclosed to building forest are paying a lot of efforts and expenses to change to green city that park and street tree get put together. By the example, 'GREEN CITY of PUSAN 21' progress to decorate army facilities like the park, and to plant street trees in several places of city plan in Pusan. And urban environment that big cities of advanced nation are agreeable is making in the large park and road street trees at several places in downtown. Because price of tree for the park is very expensive, tree management system was all-important. In this paper, Motes deliver the sensor information in each tree through radio sensor network by server side. This information can use in state grasping of tree, harmful insects courtesy call etc and this system design was suggested to inform to mode of life administration scholars.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.217-220
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• 2005

Internal cities such as gray level been enclosed to building forest are paying a lot of efforts and expenses to change to green city toot park and street tree get put together. By the example, 'GREEN CITY of PUSAN 21' progress to decorate army facilities like the park, and to plant street trees in several places of city plan in Pusan. And urban environment that big citys of advanced nation are agreeable is making in the large park and road street trees at several places in downtown. Because price of tree for the park is very expensive, tree management system was all-important. In this paper, Motes deliver the sensor information in each tree through radio sensor network by server side. This information can use in state grasping of tree, harmful insects courtesy call etc and this system design was suggested to inform to mode of life administration scholars.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.5
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• pp.1201-1210
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• 2007

The urban streets as a featured and well performing public space for people should be organized in a way that can work as a whole system through network as well as that can provide amenities fur pedestrian. This is a study on Seattle's 'Blue Ring' project for an analysis focused on how its street weaving system organized and what are the design characteristics of the streets. The results are as followings. (1)Pedestrian oriented design, (2)Urban street as a part of open space that can accommodate human activities, (3)Integrated, not isolated with outer/ other open space, (4)Organically networked in a hierarchical manner that can promote pedestrian movement, (5)Utilization of regionally identical design elements. And Smart Growth concept lies in the core of 'Blue Ring' project.

• Journal of the Korean housing association
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• v.17 no.5
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• pp.169-178
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• 2006

The purpose of this study is to provide the guidelines for housing area that consider the children's outdoor behavior. This study was complemented the limit of study method of the previous studies limiting the subject to play space in APT. So, this study was progressed the analyzation of physical characters of outdoor spaces, the observation of children's activities behavior, and the survey of children's opinion and satisfaction. Especially, 2 objective housing areas of this study were selected the deferent areas. The deferents were the structure of street, the location shape of parks, and the physical characters(accessibility, network etc.). Finally, founding on the result of this study, the 7 guidelines of housing area for children were presented : play space, park & green space, space of around the education facilities, space of around the commercial facilities, street space, square, and parking lot. This study have means that expand the objective range and use the variety study methods.

• Journal of the Korean Society of Costume
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• v.59 no.2
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• pp.128-142
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• 2009

American trendy casual style can be characterized as fitted to body and rendering sexy and fashionable images and now very popular in Korea. This paper aims to identify how American trendy casual styles have been introduced and diffused among Korean young people and also compare the similarities and differences between American and Korean styles. American trendy casual style was introduced and diffused through 4 channels: people who have living experiences in America, media exposure by American films, TV dramas and fashion magazines, on-line network using internet cafe, club and blog, use of on-line shopping mall speciallized for purchasing American apparel brands. Some of American celebrities became fashion ikons and played critical roles in diffusing American trendy styles. Photos of those American celebrities and street fashion of Korean young women were collected through internet search from Sep. 2006 to Aug. 2007. 6 styles including leggings, mini skirt, short dress, skim jeans, pants with long boots, big bag and long necklace were selected as representing American trendy casual styles. Silhouettes and overall styling were very similar in all 6 items. But Differences were found in terms of rotor, amount of details, item coordination, matching shoes and overall images.