• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.3
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• pp.271-280
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• 2004

Assessment of image registration for Pressure Sensitive Paint (PSP) was performed. A 16 bit camera and LED lamp were used with Uni-FIB paint (ISSI). Because of model displacement and deformation at 'wind-on' condition, a large error of the intensity ratio was induced between 'wind-on' and' wind-off images. To correct the error, many kinds of image registrations were tested. At first, control points were marked on the model surface to find the coefficients of polynomial transform functions between the 'wind-off' 'wind-on' images. The 2nd-order polynomial function was sufficient for representing the model displacement and deformation. An automatic detection scheme was introduced to find the exact coordinates of the control points. The present automatic detection algorithm showed more accurate and user-friendly than the manual detection algorithm. Since the coordinates of transformed pixel were not integer, five interpolation methods were applied to get the exact pixel intensity after transforming the 'wind-on' image. Among these methods, the cubic convolution interpolation scheme gave the best result.

• The KIPS Transactions:PartB
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• v.14B no.7
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• pp.493-502
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• 2007

An on-line registration technique is presented to register multi-view range images for the 3D reconstruction of real objects. Using a range camera, we first acquire range images and photometric images continuously. In the range images, we divide object and background regions using a predefined threshold value. For the coarse registration of the range images, the centroid of the images are used. After refining the registration of range images using a projection-based technique, we use a modified KLT(Kanade-Lucas-Tomasi) tracker to match photometric features in the object images. Using the modified KLT tracker, we can track image features fast and accurately. If a range image fails to register, we acquire new range images and try to register them continuously until the registration process resumes. After enough range images are registered, they are integrated into a 3D model in offline step. Experimental results and error analysis show that the proposed method can be used to reconstruct 3D model very fast and accurately.

• Korean Journal of Head & Neck Oncology
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• v.23 no.2
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• pp.147-152
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• 2007

Objectives and Background : Aims of this studies are to collect and analyze the lawful restriction against cancer registration and to suggest the model promoting the cancer registry. Materials and Methods : Total 16 countries, the members of OECD, including the U.S. are evaluated. the status of cancer registration of the evaluated countries are analyzed. The legislated laws, protect the individual's information, of the evaluated countries are analyzed. The cases any registries were impaired with the law to protect privacy are searched and analyzed. Results : All of the evaluated countries have some kinds of privacy protecting laws. For cancer registration, 11 of 16 countries implement some lawful authorities. Some of countries have experienced restriction of registration by the law of protecting individual's health data. All countries have performed cancer registry and 6 of 16 countries have nearly 100% population-based cancer registration. Conclusions : The cancer registry has to be the national effort. The informed consent of the data subjects and the permission of any special institutes are the difference to perform the registration. So, it is necessary to legislate any law supporting the cancer registration and establish any independent institutes to protect the individual's health data and support the cancer registry.

• The korean journal of orthodontics
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• v.53 no.4
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• pp.254-263
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• 2023

Objective: The evidence on the accuracy of bite registration using intraoral scanners is sparse. This study aimed to develop a new method for evaluating bite registration accuracy using intraoral scanners. Methods: Two different types of models were used; 10 stone models and 10 with acrylic resin teeth. A triangular frame with cylindrical posts at each apex (one anterior and two posteriors) was digitally designed and manufactured using three-dimensional (3D) printing. Such a structure was fitted in the lingual space of each maxillary and mandibular model so that, in occlusion, the posts would contact their opposing counterparts, enforcing a small interocclusal gap between the two arches. This ensured no tooth interference and full contact between opposing posts. Bite registration accuracy was evaluated by measuring the distance between opposing posts, with small values indicating high-accuracy. Three intraoral scanners were used: Medit i500, Primescan, and Trios 4. Viewbox software was used to measure the distance between opposing posts and compute roll and pitch. Results: The average maximum error in interocclusal registration exceeded 50 ㎛. Roll and pitch orientation errors ranged above 0.1 degrees, implying an additional interocclusal error of around 40 ㎛ or more. The models with acrylic teeth exhibited higher errors. Conclusions: A method that avoids the need for reference hardware and the imprecision of locating reference points on tooth surfaces, and offers simplicity in the assessment of bite registration with an intraoral scanner, was developed. These results suggest that intraoral scanners may exhibit clinically significant errors in reproducing the interocclusal relationships.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.4
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• pp.293-304
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• 2022

In this study, to analyze the effect of buildings on the image co-registration performance, co-registration results are compared according to the presence or absence of matching points extracted from buildings. To remove the matching points extracted from buildings, a building mask generated by extracting building objects from the digital topographic map was used. In addition, matching points extraction performance and image co-registration accuracy were analyzed according to the magnitude of the convergence angle. Image co-registration results were compared by applying the affine and piecewise linear transformation models, respectively. According to the experimental results, the affine transformation model showed an overall improvement in accuracy after removing the matching points extracted from buildings. On the other hand, the piecewise linear transformation model improved the accuracy at the checkpoints including the surrounding buildings, but the accuracy improvement was not significant at checkpoints in the flat area without the existence of buildings. In addition, when the piecewise linear transformation model was applied, stable accuracy of less than 2 pixels was derived from images with a convergence angle of 20° or less.

• Journal of KIISE:Software and Applications
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• v.32 no.1
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• pp.22-33
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• 2005

In this paper. we propose an image registration algorithm based on variable-sized blocks of ellipsoidal prototype model which is similar in shape to human face. While matching blocks, the existing cylindrical prototype model which only takes into account left and right curvature can accomplish a correct alignment on left and right images. But, registration errors are produced from up and down images because the cylindrical prototype model not reflects characteristics of head shape and jaw structure of human. The proposed method is a block matching algorithm which uses variable-sized blocks with considering left-right and up-down curvature of ellipsoidal face model and can correctly align images by using the correlation between them. We then adapt image mosaic technique to generate a face texture from aligned images. For this purpose, we stitch them with assigning linear weights according to the overlapped region and remove ghost effects to make more realistic facial texture.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1997.10a
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• pp.97-101
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• 1997

In recent years, there have been a number of applications of fuzzy logic in fuzzy reasoning system. The main objective of these applications is to approximate a decision making using the fuzzy reasoning system. This paper designs a fuzzy reasoning model for the decision making of registration fee at a private school, implements it applying for linguistic variables and fuzzy rules, and evaluates the practical availability of the model. The system accepts fuzzy rules, the type of membership functions, the domain of fuzzy sets and hedge, and fuzzifies the linguistic variables to generates fuzzy sets. The fuzzy sets generated are combined to constructs a solution fuzzy set. Finally, the system defuzzifies the solution fuzzy set to calculate a scalar value which is used for decision making.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.456-463
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• 2003

This paper presents a texture mapping method of a 3D scanned model with 2D images from different views. The texture mapping process consists of two steps Registration of the 3D facet model to the images by interactive points matching, and 3D texture mapping of the image pieces to the corresponding facets. In this paper. some implem entation issues and illustrative examples are described.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.128-135
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• 2002

An efficient mobility management for mobile stations plays an important role in mobile communication network. This paper studios a zone-based registration (ZBR) that is implemented in most of mobile communication systems. We introduce the mobility management scheme that combines a zone-based registration and a selective paging (SP) and analyze its performance. We set up an analytical model based on 2-dimensional random walk mobility model and evaluate the performance of the proposed mobility management scheme using the model to determine the optimal size of location area which will result in the minimum signaling traffic on radio channels. Numerical results are provided to demonstrate the performance of the proposed mobility management scheme under various circumstances.

• Journal of KIISE:Software and Applications
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• v.30 no.12
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• pp.1239-1246
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• 2003

Registration is the process aligning the range data sets from different views in a common coordinate system. In order to achieve a complete 3D model, we need to refine the data sets after coarse registration. One of the most popular refinery techniques is the iterative closest point (ICP) algorithm, which starts with pre-estimated overlapping regions. This paper presents an improved ICP algorithm that can automatically register multiple 3D data sets from unknown viewpoints. The sensor projection that represents the mapping of the 3D data into its associated range image is used to determine the overlapping region of two range data sets. By combining ICP algorithm with the sensor projection constraint, we can make an automatic registration of multiple 3D sets without pre-procedures that are prone to errors and any mechanical positioning device or manual assistance. The experimental results showed better performance of the proposed method on a couple of 3D data sets than previous methods.