• The korean journal of orthodontics
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• v.36 no.1 s.114
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• pp.45-54
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• 2006

Recent beauty trends have caused an increase in the number of bialveolar protrusion patients seeking treatment of lip protrusion. But studies of these patients are not common. Studies using their dental models are especially rare. Dental models have been measured manually or through a computer by digitizing two dimensional images of models. Nowadays, we are able to study dental models more easily and accurately by utilizing the three-dimensional (3-D) laser scanner in dentistry. An investigation was carried out to evaluate the characteristics of the dental arch in a bialveolar protrusion group in comparison with a normal group using 3-D digital models. The normal group was composed of 20 subjects who were selected from students of the School of Dentistry, Kyungpook National University. The bialveolar protrusion group was composed of 20 subjects who visited for treatment at the Department of Orthodontics, Kyungpook National University Hospital. Tooth size, arch width and arch length were measured digitally, and arch shape and the shape of the palate were drawn. Based on the results of this study, the differences of the arch characteristics in the bialveolar protrusion group were that the size of the teeth was larger, mandibular canine width and 1st premolar width were wider, and arch length was longer than in the normal group. And there were differences in the arch shape and the shape of palate between the bialveolar protrusion and normal groups.

• Archives of design research
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• v.19 no.1 s.63
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• pp.225-234
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• 2006

Product designers sketch various ideas of foreground figures(detail design) onto background figures(basic form) and evaluate numerous combinations of them in the late stages of design process. Designers have to test their ideas elaborately with a high-fidelity physical model that looks like a real product. However, due to the requirements of time and expense in making high-fidelity design models, it is impossible to evaluate such a number of combinatorial solutions of background and foreground figures. Contrary to digital models, physical design models are not easily modifiable and so designers cannot easily develope ideas through iterative design-evaluation process. To address these problems, we proposed a new concept 'Augmented Plasticity' that gives morphological editability to a rigid physical object using Augmented Reality technology and implemented the idea as Digital Skin system. Digital Skin system figures out the position and orientation of object surface with ARToolKit visual marker and superimposes a deformed surface image seamlessly using differential rendering method. We tried to apply Digital Skin system to detail design, redesign of product, and material exploration task. In consequence, it was found that Digital Skin system has potential to allow designers to implement and test their ideas very efficiently in the late stages of design process.

• Journal of Digital Convergence
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• v.12 no.1
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• pp.539-548
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• 2014

This study categorized the literature on instruction models by research period, theme, teaching model, class, and subject to identify research trends. The sampling period was from 1977 to March 2013, and 586 research papers were analyzed. Changes in the studies on instruction models were divided into three stages: Stage 1 (1977-1996), Stage 2 (1997-2006), and Stage 3 (2006-2007). Research papers increased rapidly from 8% in Stage 1 to 51% in Stage 2, showing a rapid increase in Stage 2. "Design and development" was the most researched theme throughout the three stages, and the most researched instruction model type was "curriculum-oriented."By subjects, it was found that studies on "cross-curriculum" were being conducted more actively than other subjects. Based on these results, this study proposes directions for future domestic research on instruction models.

• Journal of Digital Convergence
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• v.12 no.12
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• pp.277-284
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• 2014

The NHPP software reliability models for failure analysis can have, in the literature, exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, finite failure NHPP models that assuming the expected value of the defect and infinite failures NHPP models that repairing software failure point in time reflects the situation, were presented for comparing property. Commonly used in the field of software reliability based on Rayleigh distribution software reliability model finite failures and infinite failures were presented for comparison problem. As a result, infinite fault model is effectively finite fault models, respectively. The parameters estimation using maximum likelihood estimation was conducted. In this research, can be able to help software developers for considering software failure property some extent.

• Journal of Digital Contents Society
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• v.3 no.2
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• pp.221-233
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• 2002

In this paper, we present integer programming models and algorithms for the Capacitated Facility Location-Allocation Problem (CFLP). The models and algorithms can be used for the design of logistics networks and for the location of telecommunication facilities. We are given a set of candidate facility installation sites, one type of facility for each candidate site with its capacity and installation cost, a set of customers with their demand requirement, and flow cost for one unit of demand flow from each customer to each candidate site. (CFLP) is to determine the number of facilities for each candidate site and the set of customers which are connected to each site with minimum cost, while satisfying the demand requirement of each customer and constraints imposed on the allocation of customers to facilities. We present two integer programming models for (CFLP), and devise a branch-and-cut algorithm and a branch-and-price algorithm for the problem.

• Journal of Digital Convergence
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• v.19 no.7
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• pp.199-208
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• 2021

Automatic Post Editing(APE) is the study that automatically correcting errors included in the machine translated sentences. The goal of APE task is to generate error correcting models that improve translation quality, regardless of the translation system. For training these models, source sentence, machine translation, and post edit, which is manually edited by human translator, are utilized. Especially in the recent APE research, multilingual pretrained language models are being adopted, prior to the training by APE data. This study deals with multilingual pretrained language models adopted to the latest APE researches, and the specific application method for each APE study. Furthermore, based on the current research trend, we propose future research directions utilizing translation model or mBART model.

• Imaging Science in Dentistry
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• v.51 no.1
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• pp.41-47
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• 2021

Purpose: This study aimed to compare the accuracy of 3-dimensional(3D) printed models derived from multidetector computed tomography (MDCT) and cone-beam computed tomography (CBCT) systems with different fields of view (FOVs). Materials and Methods: Five human dry mandibles were used to assess the accuracy of reconstructions of anatomical landmarks, bone defects, and intra-socket dimensions by 3D printers. The measurements were made on dry mandibles using a digital caliper (gold standard). The mandibles then underwent MDCT imaging. In addition, CBCT images were obtained using Cranex 3D and NewTom 3G scanners with 2 different FOVs. The images were transferred to two 3D printers, and the digital light processing (DLP) and fused deposition modeling (FDM) techniques were used to fabricate the 3D models, respectively. The same measurements were also made on the fabricated prototypes. The values measured on the 3D models were compared with the actual values, and the differences were analyzed using the paired t-test. Results: The landmarks measured on prototypes fabricated using the FDM and DLP techniques based on all 4 imaging systems showed differences from the gold standard. No significant differences were noted between the FDM and DLP techniques. Conclusion: The 3D printers were reliable systems for maxillofacial reconstruction. In this study, scanners with smaller voxels had the highest precision, and the DLP printer showed higher accuracy in reconstructing the maxillofacial landmarks. It seemed that 3D reconstructions of the anterior region were overestimated, while the reconstructions of intra-socket dimensions and implant holes were slightly underestimated.

• Journal of the Korean Society for Library and Information Science
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• v.40 no.3
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• pp.263-287
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• 2006

With the rapid and broad changes of information media and information environment the traditional libraries have been evolving into the digital libraries. An analysis for the Planning and realization of the electronic resource management system was carried out to establish the various electronic resources in the digital library, the first in Korea. The study targeted from electronic journals, web-based databases, e-books, and to open access resources. The focus of the analysis lies in the Providing practical integrated electronic resource management for digital librarian based on the framework of effective Electronic Resource Management Initiative(ERMI) of Digital Library Federation(DLF) with network and electronic resource description. The analyses included life-cycle, subscription models, coverages. types of information provider for electronic resources. and system organization for implementation of electronic resource management system.

• Korean Journal of Geomatics
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• v.1 no.1
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• pp.51-59
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• 2001

The Government confirmed the action planning of digital mapping project for major thematic maps based on ‘Revised Plan for The Development of the National Geographic Information System’(NGIS). Mapping for major thematic maps was begun in 1998 when digital mapping project for topographic maps finished due to the delay of the action planning, and will selectively have produced the essential digital thematic maps according to the frequency of usage. The models of topographic-cadastral maps and administrative boundary maps around Suwon were produced in accordance with the presented draft. We presented specification for production of the most appropriate topographic-cadastral maps and administrative boundary maps through the analysis of the process of production, discussion and error check, and correction of the produced topographic-cadastral maps and administrative boundary maps. And we could make it easier to develop digital mapping project of topographic-cadastral maps and administrative boundary maps effectively by presenting the strategy for data input and maintenance, the cost model for carrying out the digital thematic map production, digital topographic maps, and the supplement of data model and data format. Topographic-cadastral maps has a wide range of usage but a lot of difficulties in the process of production and map update under use. So it seems that the study on users, university, private sector and municipal self-government must follow for promoting the use of topographic-cadastral maps.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.3
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• pp.241-250
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• 2000

The Government confirmed the action planning of digital mapping project for major thematic maps based on‘Revised Plan for The Development of the National Geographic Information System’(NGIS). Mapping for major thematic maps will selectively have produced the essential digital thematic maps according to the frequency of usage by the year of 2000. The models of topographic-cadastral maps around Suwon were produced in accordance with the presented draft. We presented specification for production of the most appropriate topographic-cadastral maps through the analysis of the process of production, discussion and error check, and correction of the produced topographic-cadastral maps. And we could make it easier to develop digital mapping project of topographic-cadastral maps effectively by presenting the strategy for data input and maintenance, the cost model for carrying out the digital thematic map production, digital topographic maps, and the supplement of data model and data format.