• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.10
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• pp.881-886
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• 2013

Even though a multi-view camera system is able to capture multiple images at different viewpoints, the color distributions of captured multi-view images can be inconsistent. This problem decreases the quality of multi-view images and the performance of post-image processes. In this paper, we propose an improved polynomial model for effectively correcting the color inconsistency problem. This algorithm is fully automatic without any pre-process and considers occlusion regions of the multi-view image. We use the 5th order polynomial model to define a relative mapping curve between reference and source views. Sometimes the estimated curve is seriously distorted if the dynamic range of extracted correspondences is quite low. Therefore we additionally estimate the first order polynomial model for the bottom and top regions of the dynamic range. Afterwards, colors of the source view are modified via these models. The proposed algorithm shows the good subjective results and has better objective quality than the conventional color correction algorithms.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.1
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• pp.99-107
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• 1991

The purpose of this study was to decide the proper projection angle that could avoid the superimposition of the petrous portion of temporal bone and posterior clinoid process in cephalometric lateral and basal view of the 10 dry skulls and to analyze the reproducibility of a modified Accurad-100 head holder device from Denar Co. and a cephalostat head holder in 30 transcranial radiographs of the dry skull. The results were obtained as follows: The vertical angle was 24.5±4.1° and the horizontal angle was 3.0 ±5.7°. The distances between arbitrary 3 points which were on the TMJ area were as follows: AB 16.76±0.27㎜, BC 8.79±0.18㎜ in the transcranial radiographs using modified Accurad-100 head holder, AB 29.03±0.14㎜, AC 19.95±0.24㎜, BC 10.08±0.07㎜ in the transcranial radiographs using cephalostat.

• Journal of Korean Foot and Ankle Society
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• v.8 no.1
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• pp.39-45
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• 2004

Purpose: The author modified the technique of Grice-Green, for managing flexible flat foot, with severe hindfoot valgus and possible dorsiflexion more than $15^{\circ}$. The purpose of this study was to evaluate the efficacy and results of this modified technique. Material and Methods: Total of 6 patients, 11 cases of pes planovalgus were operatively managed with Modified Grice-Green procedure from Nov. 1996 to April 2002. Total 11 cases in 6 patients were managed; 9 cases in 5 males, 2 cases in one female. The average age of the patients were 7.3 years (5.1-13.3 years). Average follow up period was 3.9 years (1.2-6.7 years). Patients were evaluated preoperatively and at last follow up radiologically and clinically. Radiologic evaluation were done by measuring the talocalcaneal and talo-$1^{st}$ metatarsal angles with the anteroposterior view; and by measuring the talo-$1^{st}$ metatarsal angles with the lateral view. The clinical outcome were rated by subjective and objective improvement level. Results: On follow up, 9 cases were complete satisfied, 2 cases were satisfied with minor reservation and no case had major reservations or dissatisfaction. Objective results were rated as excellent in 9 cases, good in 2 cases. Average preoperative talo-calcaneal and talo-$1^{st}$ metatarsal angles on anteroposterior radiograms were $34.4^{\circ}$ ($16-40^{\circ}$) and $32^{\circ}$ ($8-48^{\circ}$) respectively; which postoperatively on last follow up were $20^{\circ}$ ($3-37^{\circ}$) and $15.6^{\circ}$ ($3-34^{\circ}$) respectively. Average Preoperative talo-$1^{st}$ metatarsal angle on lateral radiogram was $18.4^{\circ}$ ($6-30^{\circ}$); which postoperatively on last follow up was $6.7^{\circ}$ ($-6-17^{\circ}$). Conclusion: Modified Grice-Green operative procedure is effective and satisfactory procedure for planovalgus deformity in children. but for more accurate results, more patients and further follow up period are needed.

• Communications for Statistical Applications and Methods
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• v.16 no.2
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• pp.277-286
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• 2009

Image registration is a process to establish the spatial correspondence between images of the same scene, which are acquired at different view points, at different times, or by different sensors. In this paper, we introduce a robust brain registration technique for correcting the difference between two temporal images by the different coordinate systems in MR and CT image obtained from the same patient. Two images are registered where this measure is minimized using a modified conditional entropy(MCE: Modified Conditional Entropy) computed from the joint histograms for the intensities of two given images, we conduct the rendering for visualization of 3D volume image.

• Journal of Multimedia Information System
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• v.1 no.1
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• pp.45-53
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• 2014

This article describes a two wheelers detection system riding on people based on modified histogram of oriented gradients (HOG) for vision based intelligent vehicles. These features used correlation coefficient parameter are able to classify variable and complicated shapes of a two wheelers according to different viewpoints as well as human appearance. Also our system maintains the simplicity of evaluation of traditional formulation while being more discriminative. In this paper, we propose an evolutionary method trained part-based models to classify multiple view-based detection: frontal, rear and side view (within $60^{\circ}C$). Our experimental results show that a two wheelers riding on people detection system based on proposed approach leads to higher detection accuracy rate than traditional features.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.3 s.234
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• pp.403-410
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• 2005

This study presents the benchmark results of several design frameworks for the purpose of developing an efficient design framework in view of Excel interface. For the benchmark, three optimum design problems are chosen and solved by using the design frameworks. In order to compare the frameworks with each other, the evaluation criteria are specified and modified to fit the problems with Excel interface. Three example cases are solved and compared. The evaluation report is summarized in terms of efficiency, ease of use, internal structure, API, etc. However, the optimization result itself is not focused because the specific optimization algorithm is not our concern. Finally, some suggestions of how to develop an efficient design framework with Excel interface are presented.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.835-840
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• 2008

Next Generation High Speed Train having a distributed electrical motor system has just been developing to aim the experimental maximum speed at 400km/h since August, 2007. This project is in stage of concept design and so, it needs to take some review and analysis the characteristics of suspensions on the view of concept design. A vehicle modeling is made of modified Korean High Speed Train bogie model with Vampire program and analyzed the effect on the dynamic performances according to the variation of primary and secondary suspension characteristics. The results would be useful to manage the potential risks in the next stage of basic and precision design that will be done by the manufacturing company.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.742-748
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• 2003

As for marine propulsion shafting system using 4 stroke diesel engine, it is common to apply reduction gear box between diesel engine and shafting with a view of increasing mechanical efficiency, which inevitably require elastic coupling due to avoid chattering and hammering inside of gear box. In this study, optimum method of rectifying propulsion shafting system in case of 750ton fishing vessel specially in a view of torsional vibration, is theoretically studied. After exchange of diesel engine and gear box, analysis result of torsional vibration get worse and so some countermeasure are needed. The elastic coupling is modified from present block type rubber coupling showing relatively high torsional stiffness to rubber coupling with two series elements directly connected. The vibration measurement using two laser torsion meters was done during sea trial, whose results are compared to those of calculation and verified.

• Korean Journal of Computational Design and Engineering
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• v.21 no.2
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• pp.151-158
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• 2016

It is important to analyze dimensional errors occurring during shipbuilding process. A ship is constructed by assembling blocks and installing outfits in assembled ship structure. Blocks and outfits have a main direction that has greater importance than other directions from the view point of dimensional error. Therefore, a main direction should have a greater weighting factor than other directions in order to achieve meaningful inspection results. In this paper, a modified point registration method based on iterative closest point (ICP) is proposed. In this method, a user determines one or two main directions among x, y, and z directions, and then each main direction is made to have a greater weighting factor than other directions. For points registration, mapping between measured points and design points are performed by the modified ICP in which weighting factor assigned to each main direction is considered.

• Transactions of Materials Processing
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• v.7 no.5
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• pp.489-495
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• 1998

Spinning is a chipless forming method for producing axially symmetric parts by using axial-radial motions of a spinning roller. This process has still some advantages in such a view point that a variety of complex shapes which can not be formed in a press can be easily spun at a low cost although it is one of the oldest forming methods for spinning mainly cookware parts for a long time. This study is to investigate the optimum roller path in order to obtain the maximum spinnability in producing cylindrical cups of Aluminum(A1050-H16) sheet metal. Working conditions applicable to any size of blank were predetermined through preliminary spinning tests. 9 types of roller path were proposed and experiments were carried out. The modified involute curve was shown to give the maximum drawing ration and more uniform quality of spun cups as compared with other results of this study. in addition thickness distribution and dimensional accuracy of spun cups were examined and discussed.