• Journal of Korean Society for Quality Management
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• v.42 no.4
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• pp.607-616
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• 2014

Purpose: This paper reviews popular measurement system indices and proposes a procedure for assessing a measurement system using two parameters with intraclass correlation and a factor for process capability. Methods: Gage Repeatability and Reproducibility(GR&R), precision-to-tolerance ratio(PTR), number of distinct categories, producer's and consumer's risks are employed to assess the measurement capabilities and discuss the relationships between measurement system metrics. Results: Two-dimensional plot by two parameters is presented to assess adequacy of the measurement system and process capability. A numerical example and previously studied case study are provided for illustration. Conclusion: The procedure proposed in this paper using two-dimension parameters provides a valuable procedure and helpful guidelines to quality and production managers in assessing the capabilities of a measurement system and choosing the needed actions to be the most benefit.

• Plant Journal
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• v.7 no.4
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• pp.77-87
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• 2011

In proportion to continuing growth of overseas plant market and the trend of its mega scale of the project, the importance of management is significantly emphasized for the successful execution of the project. And it is recognized that progress control is the most important management item amongst the others in the management. Progress control is importance of progress measurement for performance measurement and process control of project, but it is hardly obtainable securing the objectivity in the progress measurement since the progress measurement are being applied differently in accordance with the project conditions and the experience level of the person in charge for the progress control. This study has conducted as following to propose a standard method for progress measurement in a petrochemical plant protect. Domestic and overseas plant projects are investigated variously with the applied method of progress measurement, and the deduced problem of progress measurement. And then standard method for progress measurement of engineering, procurement, construction and commissioning has been proposed according to comparison and analysis of practices in domestic & overseas plant project, procedures for progress control in the globally reputed petrochemical client, company rules and recommendation of the expert in progress control.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.1054-1058
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• 1995

There have been many research works for the indirect cutting force measurement in machining process, which deal with the case of one-axis cutting process. In multi-axis cutting process, the main difficulties to estimate the cutting forces occur when the feed direction is reversed. This paper presents the indirect cutting force measurement method in contour NC milling processes by using current signals of servo motors. An artificial neural network (ANN) system are suggested. An artificial neural network(ANN) system is also implemented with a training set of experimental cutting data to measure cutting force indirectly. The input variables of the ANN system are the motor currents and the feedrates of x and y-axis servo motors, and output variable is the cutting force of each axis. A series of experimental works on the circular interpolated contour milling process with the path of a complete circle has been performed. It is concluded that by comparing the ANN system with a dynamometer measuring cutting force directil, the ANN system has a good performance.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.518-523
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• 2008

In this study, we analyzed applicability of object database, designed the concept model based on object-oriented idea for measurement data management, and applied the design model to object database. The concept model composes three sub models Infrastructure managing information model, Infrastructure measurement data model, and Measurement unit model. The process to expand measurement data of new type was executed easily without changing database schema in object database. The process to expand measurement data of new type was executed easily without changing database schema in object database. Therefore, applicability of new technology to infrastructures for building a safety management network of road bridges could be increased with object database system.

• Journal of Korea Technology Innovation Society
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• v.5 no.2
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• pp.245-256
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• 2002

Measurement standards, as being widely recognized, is necessary for national economic development and advanced industrialization. Also measurement standards give reliability and fair trade to the producers and consumers. Macro-effect of measurement standards using estimation of cost function has four effects: 1) value-added causing effect, 2) effect of employment, 3) reduction effect transaction cost, 4) reduction effect defect rates. In this study, to investigate the impacts between specific and the other industries, we used I-O Table of Korea Bank. The relation between the value-added produced by original production factors and final use is determined through production level, and the relation can be investigated with production causing coefficient matrix. In this study, it was showed that the measurement standards investments including measurement only man power of industries were increased from 1995 rapidly. The establishment and maintenance of measurement standards contributes to reduce the defect rate of products in production process and improve the confidence of the product quality. The results from this study show that measurement technology contributes to improve quality, decrease defect rate, improve production process, develope new products, reduce prime cost and increase the consumer's confidence on the firms. Since these results indicate that measurement standards are very important in the point of their vast contribution, we hope our findings can contribute to encourage measurement activities in industries.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.5
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• pp.141-148
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• 2013

There are several problems in the conventional 2-D image processing and 3-D measurement systems. In the case of the 2-D image processing system, it is not possible to detect elevation data. In a 3-D measurement system, it requires a skillful operator and a lot of time for measuring data. Also, there exist data errors depending on operators. The limitation of detecting elevation data in the 2-D image processing system can be solved by laser diodes. In this study an algorithm that measures the accurate data in a subject face to be detected by combining laser diodes and a commercial CCD camera is developed. In the development process, a planar equation is developed using laser diodes and the equation is used to obtain a normal vector. Based on the results, an algorithm that transforms commercial CCD camera coordinates to 3-D coordinates is proposed. The completed measurement method will be applied to replace a manual measurement system for vehicle bodies and parts by an automated system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.255-258
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• 1995

Surface profile is an important paramerer to evaluate accuracy of machined worpiece. It is necessary to acquire this data by in-process measurement. Recent researchers have introduced Machine Vision technique to achieve it. But it is difficult to apply it to industry field yet. In this study, in-process measuring system of surface profile is developed using CCD camera. The effect of illuminance according to incident angle is investigated and surface profile from surface tester and illuminance graph are compared experimentally.

• International Journal of Aeronautical and Space Sciences
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• v.5 no.1
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• pp.46-56
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• 2004

The verification and improvement of the measurement uncertainty have beenperformed in the altitude test facility for small gas turbine engines, which was built atthe Korea Aerospace Research Institute (KARI) in October 1999. This test is performedwith a single spool turbojet engine at several flight conditions. This paper discussesthe evaluation and validation process for the measurement uncertainty improvements usedin the altitude test facility. The evaluation process, defined as tests before the facilitymodification, shows that the major contnbutors to the measurement uncertainty are theflow meter discharge coefficient, the inlet static and total pressures, the cell pressureand the fuel flow rate. The measurement uncertainty is focused on the primary parametersof the engine performance such as airflow rate, thrust and specific fuel consumption (SFC).The validation process, defined as tests after the facility modification, shows that themeasurement uncertainty, in seal level condition, is tmproved to the acceptable level throughthe facility modification. In altitude test conditions, the measurement uncertainties arenot improved as much as the uncertainty in sea level condition.

• Design & Manufacturing
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• v.16 no.1
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• pp.1-8
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• 2022

The importance of fast and accurate body temperature measurement with a portable thermometer is increasing. In order to reduce the temperature measurement response time of the infrared ear thermometer, it is very important to develop a structure for a thermometer having an efficient heat transfer path. Most of the existing ear thermometers are single structures that do not consider thermal efficiency, which may delay measurement time and reduce measurement accuracy. Therefore, in this study, the upper part of the thermometer in contact with the ear is made of a thermally conductive material, and the lower part of the thermometer is made of a thermal barrier material so that heat can be concentrated on the infrared sensor of the thermometer by blocking the upper part of the heat. For the efficiency of production, it was intended to be manufactured through the double injection process, and for this purpose, in this paper, the optimal process parameters were derived through the double injection process analysis.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.5
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• pp.122-128
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• 2013

This paper describes the on-machine surface form evaluation of an ultra-precision cylinder for the fabrication by the compensation process. In this study, the surface form error of an ultra-precision cylinder, which was fabricated by the ultra-precision diamond turning machine with a single diamond cutting tool, was evaluated by using two capacitance-type displacement probes. Based on the measurement results, the compensation process was conducted. Since the measurement was carried out on the machine without re-mounting of the workpiece, additional fabrication for compensation process can be conducted precisely.