• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.6
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• pp.27-37
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• 2008

Applications of 3D data increase with advancement of multimedia technique and contents, and it is necessary to manage and to retrieve for 3D data efficiently. In this paper, we propose a new method using the sliced shape which extracts efficiently a feature description for shape-based retrieval of 3D models. Since the feature descriptor of 3D model should be invariant to translation, rotation and scale for its model, normalization of models requires for 3D model retrieval system. This paper uses principal component analysis(PCA) method in order to normalize all the models. The proposed algorithm finds a direction of each axis by the PCA and creates orthogonal n planes in each axis. These planes are orthogonalized with each axis, and are used to extract sliced shape image. Sliced shape image is the 2D plane created by intersecting at between 3D model and these planes. The proposed feature descriptor is a distribution of Euclidean distances from center point of sliced shape image to its outline. A performed evaluation is used for average of the normalize modified retrieval rank(ANMRR) with a standard evaluation from MPEG-7. In our experimental results, we demonstrate that the proposed method is an efficient 3D model retrieval.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.10
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• pp.523-532
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• 2003

Video on Demand(VOD) services cause high resource consumption in a video seuer, because multimedia are characterized by continuous playback, a high bandwidth requirement, and long playback duration. Patching has been proposed to save the network I/O bandwidth of a video server. To achieve true VOD, patching uses multicasting to share video streams, thereby providing immediate VOD services to users without any service latency. A communication channel is used to either multicast the entire video as a regular channel or multicast only the leading portion of a video as a Patching channel. This paper Proposes a buffering patching technique that divides regular channels, as used in patching, into sub-regular channels and regular channels to shorten the holding time of the channels. In the proposed technique, the last portion of video data, corresponding to the size of the buffering window, is not transferred by sub-regular channels, but rather downloaded and buffered in the user buffer from the latest regular channel. When simulations were performed to compare the performance of the proposed technique with that of conventional patching, the results indicated that the proposed technique was superior in terms of the defection rate, average service latency, and fairness, although the amount of video data buffered at each user station was higher than that with patching.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.931-942
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• 2010

A home network provides users with a variety of information services. The kind and quality of the services can be substantially enhanced by utilizing a variety of data from sensors. However, home networks currently limit their potential by focusing on providing multimedia services rather than services utilizing sensor data. Outdoor electronics are frequently made in a form that emphasizes only certain limited functions in contrast to home appliances. Thus, sensors with one or two functions rather than many can be used in outdoor systems and their use will be more economical than using sensor nodes indoors with more complex home appliances. In this study, we chose to work with motion sensors as they have many potential uses, and we selected a parking lot control system with to use the motion sensors. This parking lot control system was implemented and applied as part of a home network. For this purpose, we defined and implemented a protocol to manage the network in a ubiquitous sensor network environment for the wireless home network in this study. Although a network management system in a Ubiquitous Sensor Network (USN) related to this study is being advanced for other projects, the protocol interface and message system have not yet been clearly defined for use in a general purpose network or in an extension into heterogeneous kinds of networks, communication support, etc. Therefore, USN network management should be conducted for management of faults, composition, power, and applications. To verify the performance of the protocol interface designed in this study, we designed and implemented the necessary units (sensor nodes, sensor gateway, and server) for each network section and, with them, proved the validity of this study.

• Journal of KIISE:Databases
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• v.36 no.6
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• pp.434-445
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• 2009

Content-based image retrieval(CBIR) is the retrieval technique which uses the contents of images. However, in contrast to text data, multimedia data are ambiguous and there is a big difference between system's low-level representation and human's high-level concept. So it doesn't always mean that near points in the vector space are similar to user. We call this the semantic-gap problem. Due to this problem, performance of image retrieval is not good. To solve this problem, the relevance feedback(RF) which uses user's feedback information is used. But existing RF doesn't consider user's region-of-interest(ROI), and therefore, irrelevant regions are used in computing new query points. Because the system doesn't know user's ROI, RF is proceeded in the image-level. We propose a new ROI RF method which guides a user to select ROI from relevant images for the retrieval of complex satellite image, and this improves the accuracy of the image retrieval by computing more accurate query points in this paper. Also we propose a pruning technique which improves the accuracy of the image retrieval by using images not selected by the user in this paper. Experiments show the efficiency of the proposed ROI RF and the pruning technique.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.5
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• pp.659-667
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• 2019

The study examined the effects of individual, family, and environmental factors on adolescents' self-esteem. Individual factors were the adolescents' health status and their leisure activity experiences, while the family factors were families' socio-economic status(SES) and parenting styles. Three environmental factors focusing on the adolescents' school environment were studied, and they consisted of academic attachment, peer attachment, and teacher attachment. The study inquiries were as follows: which individual factors had an effect on the adolescents' self-esteem? Which family factors had an effect on the adolescents' self-esteem? Which environmental factors had an effect on the adolescents' self-esteem? Of all the factors considered in this study, which factors had the greatest effect on adolescents' self-esteem? This study used data from the 3rd Korean Child and Youth Panel survey of Korean students in the first grade of middle school, and the data were analyzed using multiple regression analysis using SPSS 18.0. The results were as follows: the most important factor that have an effect on adolescents' self-esteem was parenting style, while peer attachment, health status, and academic attachment were also found to significantly affect adolescents' self-esteem. In the conclusion, the researchers suggest various strategies based on results of the analysis to improve adolescents' self-esteem.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.7
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• pp.297-306
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• 2019

This is a longitudinal study which aims to examine the effects of the use frequency of SNS on adolescents' stress and the relationship between the former and the latter, based on big five personality factors. To this end, the valid data of 994 adolescents were collected by administering questionnaires to the cohort groups of those using Facebook twice for one year(T1-T2). An analysis of the data showed that the use frequency of Facebook(T1) had no direct effects on stress(T2), and that there was an interaction between users' personality and the use frequency. In particular, users' stress(T2) was varied depending on neuroticism among personality factors, as the use frequency of Facebook(T1) increased. The higher the use frequency of Facebook, the more the stress in the group with weak neuroticism, while the higher the use frequency of Facebook, the less the stress in other group with strong neuroticism, probably because each group has different motivation for meeting their needs for social support: the former's stress may increase, since they has relatively lower needs for social support and face more conflicts as they more frequently use Facebook, while the latter's stress may decrease, because they have relatively stronger needs for social support and are likely to acquire psychological support, as they more frequently use it.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.520-525
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• 2019

Mines are an important infrastructure for securing resources, but safety problems can arise in the course of operation. Recently, the mining process is very complicated due to the large scale and mechanization. Therefore, it is necessary to construct accurate geospatial information on mine for systematic and safe mine operation. The geospatial information construction using the existing total station has a disadvantage that a lot of work time is required because the target must be collimated and measured. In this study, the data of the mines were acquired with the total station and the 3D laser scanner, and the mine spatial information was constructed by using the shape based registration method. By using the static scanner data of some area applying the reference point surveying result of the total station, it was possible to construct the accurate result on the wide area acquired by the mobile scanner effectively. Also, the accuracy of the constructed geospatial information was evaluated and the deviation of mean 0.083m was shown. Point cloud products constructed through the research can contribute to the efficiency improvement of mine management by enabling quantitative analysis such as visualization of mine shape, distance, area and slope, and automation of drawing creation for cross section shape.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.362-371
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• 2019

The purpose of this study is to recognize kindergarten teachers' experiences of child violence for identifying the site's needs for the implementation of preventive education in early childhood and to provide basic data on child violence. To this end, nine teachers were interviewed in-depth. From the study results, first, child violence-related child behavior, which usually occurs in kindergartens, includes physical assault, aggression, verbal violence, threats and threats, and bullying. Second, teachers usually use direct intervention laws in cases of child violence, but were finding it difficult to intervene properly with many tasks or high teacher-to-child ratios. Teachers recognized the need for lower teacher-to-child ratios and placement of each class burden. Third, teachers were aware of the need for prevention education for child violence targeting infants, and instigated the following appropriate interactions immediately after problem behavior occurred: large group activities, specific multimedia education data and parent education. Fourth, teachers are concerned about the possibility of problem behavior being learned and imitated through education in the implementation of prevention education for children's violence. Therefore, this study proposed the need to develop various teaching methods that could be applied to infant education sites, focusing on the types of child violence-related problem behaviors that occur in kindergartens.

• Journal of the Korean Society for information Management
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• v.38 no.1
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• pp.25-51
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• 2021

In this study, we tried to provide basic materials necessary for introduction of smart libraries by analyzing present conditions of its operation based on the actual conditions of digital materials. For this study, a survey of actual use of digital materials is conducted for digital material rooms of public libraries in nationwide and 213 persons in charge of digital materials. As a result of this study, the followings are found: first, 80.8% of those public libraries responding to the survey operate digital material rooms and average 1.75 person is in charge of managing digital materials and open type Wi-Fis are installed in those public libraties but only 11.3% of those libraries provide 5G services; second, it is found that the digital data which are owned by those public libraries most are video contents (63.8%), e-books (53.5%) and audio books (53.5%) in order. In addition average number of types of audio books 781, video contents 4,985, nonbook contents except for video 3,616 and other digital data 626. This study is a basic research for introduction of smart library and it is necessary to conduct another study of a plan for future revitalization of digital materials and librarians' awareness on introduction of smart library.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.3
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• pp.169-175
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• 2022

Korea's construction industry has a shortage and aging of construction manpower, low productivity compared to other industries, and a high rate of industrial accidents. The Ministry of Land, Infrastructure and Transport is preparing for the 4th industrial revolution and is expanding investment in construction automation and innovative growth engines to improve productivity in the construction industry. In order for new technologies to be utilized in the road construction field, the accuracy of the technologies and the applicability of each type of work must be evaluated. In this study, the accuracy of the mobile mapping system was tried to verify based on the relevant work regulations, and to suggest the applicability of the mobile mapping system to high-speed driving tracks through data acquisition and analysis on road construction sites. The accuracy of the equipment used in the study was verified in accordance with the relevant work regulations, and the possibility of applying the mobile mapping system used for the study to road construction surveying was presented with a maximum error of less than 10cm in the horizontal and vertical directions. In addition, the possibility of utilizing the road construction survey using the mobile mapping system was presented through comparison with the existing method for data acquisition time for construction surveying, production of construction status survey results, and calculation of heatmap and earthworks. In the future, the use of construction status surveying of the mobile mapping system will greatly improve the efficiency of construction work.