• Journal of Information Processing Systems
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• v.9 no.4
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• pp.511-537
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• 2013

Numerous data intensive applications demand the efficient processing of a new type of query, which is called a progressive query (PQ). A PQ consists of a set of unpredictable but inter-related step-queries (SQ) that are specified by its user in a sequence of steps. A conventional DBMS was not designed to efficiently process such PQs. In our earlier work, we introduced a materialized view based approach for efficiently processing PQs, where the focus was on selecting promising views for materialization. The problem of how to efficiently find usable views from the materialized set in order to answer the SQs for a PQ remains open. In this paper, we present a new index technique, called the Dynamic Materialized View Index (DMVI), to rapidly discover usable views for answering a given SQ. The structure of the proposed index is a special ordered tree where the SQ domain tables are used as search keys and some bitmaps are kept at the leaf nodes for refined filtering. A two-level priority rule is adopted to order domain tables in the tree, which facilitates the efficient maintenance of the tree by taking into account the dynamic characteristics of various types of materialized views for PQs. The bitmap encoding methods and the strategies/algorithms to construct, search, and maintain the DMVI are suggested. The extensive experimental results demonstrate that our index technique is quite promising in improving the performance of the materialized view based query processing approach for PQs.

• Journal of the Korean Society of Radiology
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• v.17 no.7
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• pp.1099-1108
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• 2023

The mortise view radiography procedure is an ankle joint examination and observes the presence of trauma, sprain, or dislocation suspected in the ankle joint. The auxiliary equipment used during the mortise view radiography procedure can generate artifacts in the radiograph images and is not diverse enough to be custom-made for each patient; not cost-efficient. The purpose of this study is to create a custom assistive device to support mortise view radiography procedure. This study utilized 3D printing technology to create the mortise view radiography procedure assistive device (ShinHan Device; SHD). The lengths of the tibiotalar joint (TTJ), talar calcaneal joint (TCJ), and medial joint (MJ) were measured and evaluated by five researchers using both SHD and the prototype Hologic tool. The mean ranges were found to be 39.42-39.47 mm for TTJ, 31.41-31.57 mm for TCJ, and 21.21-21.23 mm for MJ while using SHD device. On the other hand, the measurements showed mean ranges of 39.73-39.79 mm for TTJ, 31.46-31.50 mm for TCJ, and 21.31-21.35 mm for MJ while using the Hologic tool. Based on this study results, the error ranges at all positions decreased by 24% for TTJ, 17% for TCJ, and 36% for MJ when using SHD device compared to the Hologic tool. Moreover, when SHD was used, it allowed for a highly reproducible examination posture (ICC = 0.99), and it enabled the acquisition of radiograph images without artifacts, which were present in the Hologic tool.

• Journal of Environmental Science International
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• v.12 no.9
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• pp.921-934
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• 2003

The purpose of this study is to identify the characteristics and differences of borrowed landscape in traditional arbors and temples in Jeonbuk province. And this study is attempted to widespread the width of understanding the traditional landscape borrowing method for contributing in modem reception and creation of landscape architectural culture. For this, 30 traditional arbors and 30 traditional temples in Jeonbuk province were selected. The orientation of the place of view point, distance, vertical and horizontal angle were surveyed for identifying the structure of borrowed landscape. Furthermore main element, auxiliary element and a media of borrowed landscape were surveyed also. Two hypothesis were established for verifying the feasibility and real effectiveness of research results. First, the willingness of borrowed landscape shall be being in establishing traditional arbors and temples. Second, this willingness of borrowed landscape shall be accomplished in arbor space more positively than in temple space. The results of this study are as follows; 1. In temples, the surrounding landscape adapted in Buddhism principles are principally expressed, whereas in arbors, congregating landscape, variety landscape, background landscape for establishing good view point and enframed landscape are induced for making authoritative landscape as various borrowed landscape techniques. 2. The distance to borrowed landscape in temples is involved in far landscape region, whereas that in arbors is in middle and near. In comparative with temples, the arbors shows variety in distance to the borrowed landscape objects. 3. Down view borrowing is used generally in arbors, whereas upper view borrowing is used in temples at the view angle to the borrowed landscape objects. 4. Borrowed landscape objects are more considered factors than view scope in arbors. Main elements for borrowing landscape are very various arbors, but those are simple as mountains and peaks in temples. And natural elements are much more than artificial things in arbors as a media of borrowing landscape in comparative with temples.

• Journal of the Korean Society of Radiology
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• v.11 no.7
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• pp.655-661
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• 2017

Sparse view CT has been widely used to reduce radiation dose to patient in radiation therapy. In this work, we performed sinogram restoration from sparse sampling data by using inpainting method for simulation and experiment. Sinogram restoration was performed in accordance with sampling angle and restoration method, and their results were validated with root mean square error (RMSE) and image profiles. Simulation and experiment are designed to fan beam scan for various projection angles. Sparse data in sinogram were restored by using linear interpolation and inpainting method. Then, the restored sinogram was reconstructed with filtered backprojection (FBP) algorithm. The results showed that RMSE and image profiles were depended on the projection angles and restoration method. Based on the simulation and experiment, we found that inpainting method could be improved for sinogram restoration in comparison to linear interpolation method for estimating RMSE and image profiles.

• Journal of Broadcast Engineering
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• v.13 no.6
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• pp.859-874
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• 2008

In this paper, we develop a fast view synthesis method that generates multiple intermediate views in real-time for the 3D display system when the camera geometry and depth map of reference views are given in advance. The proposed method achieves faster view synthesis than previous approaches in GPU by processing in parallel the entire computations required for the view synthesis. Specifically, we use $CUDA^{TM}$ (by NVIDIA) to control GPU device. For increasing the processing speed, we adapted all the processes for the view synthesis to single instruction multiple data (SIMD) structure that is a main feature of CUDA, maximized the use of the high-speed memories on GPU device, and optimized the implementation. As a result, we could synthesize 9 intermediate view images with the size of 720 by 480 pixels within 0.128 second.

• Journal of the Korean Society of Earth Science Education
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• v.16 no.1
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• pp.30-42
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• 2023

The purpose of this study is to quantitatively and qualitatively analyze the science journals written by pre-service elementary school teachers, and to categorize the view on the nature of science and the process of their change. For this purpose, 112 science journals written by 13 pre-service elementary school teachers were analyzed. The frequency of each area was analyzed using the research framework of the four areas of the nature of science, and the pattern of change in perspective on the nature of science was inductively derived and classified using the VNOS-C test analysis framework. As a result, The nature of scientific thinking, nature of scientific knowledge, nature of STS, and nature of scientific inquiry were described in relatively similar proportions, but among them, The nature of scientific thinking appeared in the largest percentage, and the nature of scientific inquiry was described in the smallest percentage. The variability of scientific knowledge, the importance of empirical evidence, and the positive and negative effects of science were especially intensively addressed. In addition, the changing aspects of pre-service elementary school teachers' perspectives on the nature of science could be categorized into 'naive view maintenance type', 'informed view maintenance type', 'regression type', 'development type', and 'mixed type'. The element of 'the empirical nature of scientific knowledge' showed various patterns of change depending on the students, and most of the students maintained a informed view on the tentativeness of scientific knowledge for several sessions.

• Science of Emotion and Sensibility
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• v.25 no.3
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• pp.3-14
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• 2022

With the increase of video conferencing users and the development of technology, the situations where video conferencing is used and the layout of video conferencing interfaces are diversifying. Social anxiety affects video conferencing communication and is closely related to the self-view function, which is characteristic of video conferencing. The self-view function is part of the video conferencing interface that provides a small preview of one's own camera feed. Self-view is known to degrade work performance and cause fatigue; however, it is set as the default function on video conferencing software in a way that users generally prefer. This study used an online survey to study the effect of task orientation, preferred self-view size, and social anxiety on video feedback preference. Participants responded to questions assessing work orientation, social anxiety level, preferred self-view size, and self-view preference. The results showed that preferred self-view size mediates task orientation and video feedback preference. There was no significant difference in the mediating effect of the preferred self-view size according to the degree of social anxiety. These results offer insights into the interactions between users and video conferencing software and provide information that can be useful for designing video conferencing interfaces.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.3
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• pp.1722-1741
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• 2017

Intrusion detection techniques based on virtual machine introspection (VMI) provide high temper-resistance in comparison with traditional in-host anti-virus tools. However, the presence of semantic gap also leads to the performance and compatibility problems. In order to map raw bits of hardware to meaningful information of virtual machine, detailed knowledge of different guest OS is required. In this work, we present VDSM, a lightweight and general approach based on driver separation mechanism: divide semantic view reconstruction into online driver of view generation and offline driver of semantics extraction. We have developed a prototype of VDSM and used it to do intrusion detection on 13 operation systems. The evaluation results show VDSM is effective and practical with a small performance overhead.

• The korean journal of orthodontics
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• v.35 no.3 s.110
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• pp.174-181
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• 2005

Understanding the level of a person's perception of changes that have occurred on the face after orthodontic treatment is critical to the process of orthodontic diagnosis and treatment planning. The purpose of this study was to determine the level of perception of profile and frontal changes in lower facial height. Forty students attending art school participated in a study evaluating the level of a participant's perception of changes in the lower facial height. Participants compared computer-graphic frontal and profile photographs with balanced proportions and photograph simulations of 1, 2, 3, and 4mm changes in lower facial height from stomion to the chin. At least a 2 mm change in lower facial height for the profile view and 3mm in the frontal view was needed to be perceived after orthodontic treatment. The level of a person's perception of the change in lower facial height was more sensitive in the profile view than in the frontal view, and information about facial changes given prior to evaluation enhanced the level of perception.

• Journal of the Korean Data and Information Science Society
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• v.25 no.1
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• pp.11-18
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• 2014

The object of study is to verify the accuracy of internet survey by comparing database data and internet survey. Internet survey was conducted on August, 2012. Respondents were subscribers of KISTI NDSL. Variables were age, organization as demographic variables, number of use, and period of use as attitude variables. Mismatch rates of age, organization, number of use, and period, are 7.5%, 5%, 92%, and 55% respectively. We could estimate the mismatch rate for age as 3% as a pessimistic point of view, and 1% as an optimistic point of view by detail verification. The mismatch rates of organization are 4.5% as a pessimistic point of view, and 2% as an optimistic point of view. The mismatch rates for the frequency of use, the period of use are very high, because measurement error, problems in memory, and internet attitude, etc. Implication of this study is that data of internet survey could be reliable. Many further researches are needed for verification of internet survey.