• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.838-841
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• 2000

To improve the accuracy of products and improve the product quality, we need to enhance the machining accuracy of the machine tools. To this point of view, measurement and inspection of finished part as well as error analysis of machine tools has been studied for last several decades. OMM(On the Machine Measurement) has been issued to alternate with CMM, pointing out disadvantages of high expenses and lots of setting time in CMM. In this paper, we study 1) the spherical surface manufacturing by volumetric error compensation of machine tool, 2) the system development of OMM without detaching work piece from a bed of machine tool after working. 3) the generation of the finished part profile by On the machine measurement. Furthermore, the output of OMM is compared with that of CMM, and verified the feasibility of the measurement system.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.7
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• pp.1003-1011
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• 2009

This study aims at precise control of oil outlet temperature in the oil cooler system of machine tools for enhancement of working speed and processing accuracy. PID control logic is adopted to obtain desired oil outlet temperature of the oil cooler system with hot-gas bypass method. We showed that the gains of PID controller could be easily determined by using gain tuning methods to get the gain of PID controller without any mathematical model. We also investigated various gain tuning methods to design the gains of PID and compared each control performance for selecting the optimal tuning method on the hot gas bypass method through experiments. Moreover, we confirmed excellent control performance with proposed PI controller gain even though disturbances were abruptly added to the experimental system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.917-921
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• 2000

One of the major limitations of productivity and quality in machining is machining accuracy of the machine tools. The machining accuracy is affected by geometric, volumetric errors of the machine tools. This paper suggests the enhancement method of machining accuracy for precision machining of high quality metal reflection mirror or optics lens, etc. In this paper, we study 1) the compensation of linear pitch error with NC controller compensation function using laser interferometer measurement, 2) the method for enhancing the accuracy of NC milling machining by modeling and compensation of volumetric error, 3) the generation of the parabolic face profile. And the method is verified by the parabolic face machining experiment with a vertical three axes NC milling machine. After this study, we will inspect using On-machine measurement and study the repetitive machining by a compensated path

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.663-667
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• 2000

The spindle unit is core parts in high precision machine tools. Diverse static and dynamic charateristics of spindle unit are needed for special purpose of machine tools. Specially, high damping ability may be very useful to high precision and high speed spindle unit. But commercial bearing system has very low damping value and high stiffness. In this paper, the combined bearing system with ball-hydrostatic bearing is suggested for high damping spindle unit. The suggested bearing system has 30% damping ability more than general ball bearing's. The average rotational accuracy of spindle with combined bearing in working speed is 24% better than with ball bearing. The unbalance rotating experiment in spindle show that rotating error with combined bearing is only half value of with ball bearing.

• Proceedings of the Korean Society for Quality Management Conference
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• 2009.10a
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• pp.370-376
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• 2009

Study of IFI(Integrated Field Innovation) means change of management. This study sill introduces IFI which is a new methodology of change and innovation of workers, and will describe how workers participated in the activities voluntarily. The principle of IFI is that letting employees to find the problems of the sites -anything that makes employees considering as the problem while they are working-and solve those problems through any tools own their own. Workers do not have to waste their time on bounding by unnecessary tools and processes. There are some cases that company "D" has been actually applied the IFI methodology in 2008. By application of IFI methodology to "D" company, which is proved that methodology is good change management program for workers who work in the manufacturing field.

• Journal of the Korean Society of Safety
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• v.20 no.1 s.69
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• pp.148-152
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• 2005

The purpose of this paper is to investigate risk factors and ergonomically improve the manufacturing lines of compressors for prevention of work-related musculoskeletal disorders, enhancement of productivity, and workers satisfaction We executed questionnaire survey, ergonomic risk factors investigation of manufacturing lines and ergonomic intervention of work methods, workplace and hand tools. The results of the questionnaire showed that $7.9\%$ of respondents were positive in WMSDs symptom survey. In ergonomic evaluation, the analysis methods such as RULA and NIOSH lifting equation were used and 28 processes in the lines were evaluated to be potentially hazardous. We ergonomically improved the processes to reduce potential WMSDs hazards : manual material handling, carts, work tables, transport methods, working posture and hand tools.

• International Journal of Contents
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• v.3 no.3
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• pp.32-37
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• 2007

Up to now, several tools to evaluate visual perception tests have been introduced for different purposes. However, they were mostly manual tools, paper books in which the therapists would turn the pages while working together with patients. This paper discusses a potential plan to develop motor-free visual perception test software for Korean patients with brain injury, and to construct a centralized database for their evaluated data in a client/server environment. Through its development, we eventually hope to achieve effective management of the data for better understanding of patients' visual perceptual skills and the standardization of the evaluation for Korean patients. With the help of the computerized environment, we also expect some advantages such as acquisition of reliable results from patients with brain injury, automation for storing and accessing patients' data, construction of the patients' database and the management of a vast amount of the data within it and the provision of a foundation to promote further development of various perceptual-cognitive rehabilitation programs.

• Journal of Computational Design and Engineering
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• v.1 no.1
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• pp.67-77
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• 2014

Most engineering software tools use typical menu-based user interfaces, and they may not be suitable for learning tools because the solution processes are hidden and students can only see the results. An educational tool for simple beam analyses is developed using a pen-based user interface with a computer so students can write and sketch by hand. The geometry of beam sections is sketched, and a shape matching technique is used to recognize the sketch. Various beam loads are added by sketching gestures or writing singularity functions. Students sketch the distributions of the loadings by sketching the graphs, and they are automatically checked and the system provides aids in grading the graphs. Students receive interactive graphical feedback for better learning experiences while they are working on solving the problems.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.59-64
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• 2006

In this paper, developed a uninterruptible hotline tools and method for replacement of strain pole crossarm on overhead distribution line. For practical use of developed tools, following direct hot-line methods were proposed: 'Direct hot-line method for replacement of pin pole crossarm', 'Direct hot-line method for alteration of crossarm' and 'Crossarm replacement method in uninterruptible cable displacement area'. These methods were proposed more simple and safe working on hotline job.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.12
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• pp.2126-2131
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• 2006

This paper proposes an international trend and its implementation for an E-Navigation that can utilize of existing and new navigation tools, in particular electronic tools, in a holistic and systematic manner. IMO develops a broad strategy for incorporating the use of new technologies in a structured way to ensure that their use is compliant with the various electronic navigational and communication technologies and services that are already available. Implementation of this new strategic vision might require modifications to working methods and navigational tools, such as chats, bridge display equipment, electronic aids to navigation, communications and shore infrastructure. E-Navigation will reduce navigational accidents errors and failures by developing standards an accurate and cost effective system.