• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.10
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• pp.2489-2496
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• 2014

The existing ship repair tool management system based on hand writing has many problems such as frequent loss of tool and overdue. To solve this problem, same systems have adopted the bar-code system. However, the systems can't cope with a problem to substitute spurious tool for genuine one on bar-code damage. Therefore, additional validation steps are necessary in order to manage expensive ship repair tool. In this paper, we propose an image comparison method for ship repair tool management. To be more concrete, we propose a normalization method and determination conditions for image comparison to use characteristics of mobile device. The normalization method makes use of the characteristics of mobile device that provides functions of real time recording, overlapping and cropping images. The proposed method applies three conditions(sum of inner angles, size of angle, position of corner coordinates) into the comparison module. The implemented system shows good performance on change direction, lighting, size and etc. The accuracy is more than 95%.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.4
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• pp.177-183
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• 2015

Incremental sheet metal forming is a manufacturing process to produce thin parts using sheet metals by a series of small incremental deformation. The process rarely needs dedicated dies and molds, thus, preparation time for the process is relatively short as to be compared to conventional metal forming. Spring back in sheet metal working is very common, which causes critical errors in dimensions. Incremental sheet metal forming is not fully investigated yet. Hence, incremental sheet metal forming frequently produces inaccurate parts. This paper proposes a method to minimize dimensional errors to improve shape accuracy of products manufactured by incremental forming. This study conducts experiments using an exclusive incremental forming machine and the material for these experiments are sheets of aluminum AL1015. This research defines a process parameter and selects a few factors for the experiments. The parameters employed in this paper are tool feed rate, tool diameter, step depth, material thickness, forming method, dies applied, and tool path method. In addition, their levels for each factor are determined. The plan of the experiments is designed using orthogonal array $L_8$ ($2^7$) which requires minimum number of experiments. Based on the measurements, dimensional errors are collected both on the tool contacted surfaces and on the non-contacted surfaces. The distances between the formed surfaces and the CAD models are scanned and recorded using a commercial software product. These collected data are statistically analyzed and ANOVAs (analysis of variances) are drawn up. From the ANOVAs, this paper concludes that the process parameters of tool diameter, forming depth, and forming method are the significant factors to reduce the errors on the tool contacted surface. On the other hand, the experimental factors of forming method and dies applied are the significant factors on the non-contacted surface. However, the negative forming method always produces better accuracy than the positive forming method.

• Journal of Trauma and Injury
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• v.36 no.1
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• pp.32-38
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• 2023

Purpose: This study aimed to identify the characteristics of patients injured by high-rotation cutting tools and the factors related to the severity of their injuries. Methods: Adult patients (≥18 years), who presented to the emergency department (ED) after a high-rotation cutting tool injury and who were registered in the Korean Emergency Department-based Injury In-Depth Surveillance (2011-2018) database, were included. Patients' demographic characteristics, injury-related factors, and Injury Severity Scores were collected. All included cases were categorized into two groups according to the tool that caused the injury: grinder versus nongrinder. The characteristics of the two groups were compared, and the factors associated with the severity of injuries were investigated. Results: Among 8,697 ED visits, 4,603 patients had been using a grinder and 4,094 had been using a nongrinder tool. The most frequently injured body part while using a grinder was the hand (46.4%), followed by the head (23.0%). While using a nongrinder tool, the most frequently injured body part was also the hand (64.0%), followed by the lower leg (11.4%). The odds of a severe injury were affected by patient age (odds ratio [OR], 1.024; 95% confidence interval [CI], 1.020-1.028) and using a grinder (OR, 2.073; 95% CI, 1.877-2.290). The odds of a severe injury using a grinder were higher in arm injuries (OR, 1.60; 95% CI, 1.40-1.83) and multiple-part injuries (OR, 1.998; 95% CI, 1.639-2.437). The odds of a severe injury using a grinder were lower for head injuries (OR, 0.481; 95% CI, 0.297-0.781). Conclusions: Injuries from grinders were more likely to affect the head and neck than nongrinder injuries, despite the lower severity. The current lack of regulations on grinders in occupational safety and health standards warrants relevant legislation and the development of applicable safety equipment.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.7
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• pp.1424-1434
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• 2009

DNA computing-inspired pattern classification based on the hypernetwork model is a novel approach to pattern classification problems. The hypernetwork model has been shown to be a powerful tool for multi-class data analysis. However, the ordinary hypernetwork model has limitations, such as operating sequentially only. In this paper, we propose a efficient implementing method of DNA computing-inspired pattern classifier using GPU. We show simulation results of multi-class pattern classification from hand-written digit data, DNA microarray data and 8 category scene data for performance evaluation. and we also compare of operation time of the proposed DNA computing-inspired pattern classifier on each operating environments such as CPU and GPU. Experiment results show competitive diagnosis results over other conventional machine learning algorithms. We could confirm the proposed DNA computing-inspired pattern classifier, designed on GPU using CUDA platform, which is suitable for multi-class data classification. And its operating speed is fast enough to comply point-of-care diagnostic purpose and real-time scene categorization and hand-written digit data classification.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.85-90
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• 2001

Recent general Press brake has many problems in cutting high accurate products in the progress of industry. Previous hand-operated press brake needs many pre-processing works to adjust bending ang1e and marking-off works to calculate bending length. Also, the hand-operating work makes many geometric errors and has difficulty for variety-mass production. To solve these problems, this paper proposes Computer Numerical Control (CNC) general press brake and development of servo-control system based on database for reduction of geometric errors and pre-processing work time and high accuracy bending work.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.4 no.1
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• pp.39-47
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• 2006

Functional Electrical Stimulation(FES) cause paralysed muscles to contract in some clinical circumstances. Generally, FES has been thought of as a valuable tool in activating any skeletal muscle paralysed as a result of upper motor neuron damage. But, the function of cardiac and smooth muscle is also affected by upper motor neuron damage. Today, various applications of FES are investigated, including conditioning cardiovascular exercise, caugh and breathing assistant, improving bowel and bladder control, hand grasp, standing and walking etc. This review will focus on the literature reporting application of FES to control respiratory capabilities and internal organ function as well as increase muscular strength, hand grasp, standing and walking in patients with upper motor diseases.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.97-101
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• 1995

This paper describes a new surface finishing process which uses magnetic abrasive polishing. This is applied to automatic finishing of die & mold surface. Nowadays, most of die & mold meanufaturing procedures have been automated by the introduction of NC machine tool and CAD/CAM system. But the surface finishing of die & mold must be done by hand work of well-skilled workers. Though many attempts were tried in the past 15 years to eliminate this hand work, the automatic finishing of die & mold surface with 3D curvature has not been achieved yet. New magnetic abrasive finishing process is thought as one of the possible methods for the automation of 3D surface finishing. In order to improve the grindability of the method, ultra-high speed and 5-axis machining was introduce. The magnetic abrasive polishing which has adopted these methods was confirmend to improve the efficiencyof die & mold surface finishing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.98-102
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• 1994

There are many difficulties in automatic polishing for die & mold surfaces. Even though the process has been studied in the past 15 years, it has not been achieved yet, but by the process of actual hand work of well-skilled workers. A new magentic assisted polishing process, which is one of the potential method for automation of surface finishing has been studied in the past 10 years by colleagues. The process has many merits, but on the other hand also has demerits, one being low efficiency of gridability by comparision with grinding wheel polish. Therefore, some attempts were tried to improve the grindability by adopting electropolishing, ultra-high speed milling, 5-axis controlled machine etc... most recently by collegues. This study also aims to improve the efficiency of polishing by introducing the easily-polished shape surface milling method equalizing the tool feed per tooth to the pick feed. This milling method was experimentally confirmed to have sufficient grindability to polish milled surface (with 10 .mu. mRmax surface roughness) into mirror surface (with 0.4 .mu. mRmax surface roughness).

• Journal of the Korean Society of Industry Convergence
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• v.9 no.3
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• pp.221-228
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• 2006

As Industrialization gets more and more advanced, human technological medical apparatus for dentistry has been developed. Such a medical apparatus have to let precision revolution and torque control facilitate. Consequently, Development of Micro hand-piece with strong durability should be required. Moreover, It's also very important to evaluate performance of such a Micro hand-piece, Evaluation of Mechanical property of Material and ANOVA have been known as useful methods in the field of Quality Evaluation. For Verification of Quality Evaluation, It has been evaluated by One-way layout ANOVA based on the data of Surface Roughness Test. Anyhow, This test has been respectively carried out by 3 kinds of Test and Superior performance has appeared in the Test result.

• Journal of Korea Multimedia Society
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• v.14 no.10
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• pp.1348-1364
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• 2011

As the existing edutainment contents for children are mostly comprised of educational tools which unilaterally induce educatees to passively respond to them, the content-creating methodologies in terms of which active and voluntary learning is made possible is urgently needed. In this paper, we present the implementation of the tangible 'electronic dice' interface as an interactive tool for behavior-based edutainment contents, and propose a methodology for developing edutainment contents for children by utilizing the recognition technique of hand movement based on depth-image information. Also proposed in the paper are an authoring and management tool of learning quizzes that allows educators to set up and manage their learning courseware, and a log analysis system of learning achievement for real-time monitoring of educational progress. The behavior-based tangible interface and edutainment contents that we propose provide the easy-to-operate interaction with a real object, which augments educatees' interest in learning, thus leading to their active and voluntary attitude toward learning. Furthermore, The authoring and management tool and log analysis system allow us to construct learning programs by children's achievement level and to monitor in real-time the learning development of children educatees by understanding the situation and behavior of their learning development from the analytic results obtained by observing the processes of educatees' solving problems for themselves, and utilizing them for evaluation materials for lesson plans.