• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.4
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• pp.343-351
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• 2004

The flaw assessment method based on ${delta}_5$ parameter was recently proposed and put to the practical use. However: since it is almost impossible to measure the ${delta}_5$ by the existing commercial clip gager, we need to develope the specially designed gages which are suitable for that purpose. In this research, a double cantilever type ${delta}_5$ clip gage with the traveling distance of 4mm was developed by the finite element analysis and the construction of Wheatstone bridge circuit including strain gages. The linearity of developed ${delta}_5$ clip gage was evaluated by the MTS extensometer calibrator with the proper adapters which allow the 6s clip gage to sit on the calibrator. Consequently, the 6s clip gage revealed the good linearity between the output voltage and the traveling distance of gage.

• Journal of Korean Society for Quality Management
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• v.44 no.1
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• pp.77-94
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• 2016

Purpose: This paper reviews Type 1 Gage study, Gage R&R study, and procedure of ISO 22514-7 for assessing a measurement system, and discusses some relationships between the measurement capability indices. Methods: The gage capability index $C_g$ of Type 1 Gage study, precision-to-tolerance ratio PTR of Gage R&R study, and measurement performance ratio $Q_{MS}$ and $Q_{MP}$ of ISO 22514-7 are considered in this paper. Results: This paper derives the relationships between $C_g$ and $Q_{MS}$, PTR and $Q_{MP}$, and $Q_{MS}$ and $Q_{MP}$, respectively, and discusses the acceptance conditions for each procedures. Conclusion: The measurement capability analysis is the first step for the quality improvement of the manufacturing processes. Therefore the result of this study provides a helpful guidelines for assessing the measurement system, enabling proper evaluation of manufacturing processes.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.304-309
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• 2000

Strain gage method is used to evaluate the mode I dynamic stress intensity factor of marging steel(18Ni) and titanium alloy(Ti-6A1-4V). To decide the best strain gage position on specimen, static fracture toughness test was performed. Then instrumented charpy impact test and dynamic tensile test was performed by using strain gage method for evlauating dynamic stress intensity factor. Strain gage signals on the crack tip region are used to calculate the stress intensity factors. It is found that strain gage method is more useful than method by using load which is obtained from impact tup to assess dynamic characteristics such as dynamic stress intensity factor.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.55
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• pp.13-24
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• 2000

6 sigma movement is the most prominent quality improvement methodology in practice. Measurement plays an important role in helping any organization improve quality. Therefore, the measurement systems analysis is the first step for the quality improvement of manufacturing process in 6 sigma movement. In this study, we investigate the effect of Gage Repeatability and Reproducibility(Gage R&R) in view of defect rate and process capability indices, and provide guidelines for acceptance of gage repeatability and reproducibility(%R&R) for six sigma quality.

• IE interfaces
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• v.18 no.4
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• pp.444-453
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• 2005

The purpose of the Gage R&R study is to determine whether a measurement system is adequate for monitoring a process. If the measurement system variation is small relative to the process variation, then the measurement system is deemed "adequate". The sources of variation associated with the measurement system are compared using an analysis of variance (ANOVA) model, in general. A typical ANOVA model used in a standard Gage R&R study is the two-factor random effect model. Then, the ANOVA partitions the total variation into three categories: repeatability, reproducibility, part variation. However, if the process variation possesses the between group variation, within group variation, and within part variation, these variations can cause the measurement system evaluation to provide misleading results. That is, in the standard Gage R&R study these variations affect the estimate of repeatability, reproducibility, or both. This paper presents a four-factor nested factorial ANOVA model which explicitly considers these variations for the Gage R&R study. The variance component estimators are derived by setting the EMS equations equal to the corresponding mean square from the ANOVA table and solving. And the proposed model is compared with the standard Gage R&R model.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.8
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• pp.147-155
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• 1995

Recent experimental studies have been shown that strain gages can be employed to determine either static or dynamic stress intensity factors $K_{I}$ wiht relatively simple experiments. However, it does not usually provide a reliable value of stress intensity factor because of local yielding and limited regions for strain gage placement at the vicinity of the crack tip. This paper attempted to define a valid region and to indicate procedures for locating and orienting the strain gage to determine static toughness $K_{Is}$ accurately form one strain gage readings with respect to varying loadings. The strain gage methods was used for compact tension specimens made of Polycarbonate and PMMA(polymethyl methacrylate). Series expansions of the static and dynamic strain fields are applied. Strain gage orientation and location are then studied to optimize the strain response. Especially, in the dynamic experiment, the specimen employed is an oversized Charpy V-notch specimen which has been modified to provide significant constraint with a large elevation of the flow stress. The impact behavior of the specimen is monitored by placing strain gage near the crack tip. The dynamic toughness $K_{Id}$ is determined from the strain time traces of this gage.e.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.129-135
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• 2012

Companies strive for quality improvement and use process data obtained through measurement process to monitor and control the process. Measurement data contain variation due to error of operator and instrument. The total variation is sum of product variation and measurement variation. Gage R&R is for repeatability and reproducibility of measurement system. Gage R&R study is usually conducted to analyze the measurement process. In performing the gage R&R study, several parameters such as the appropriate number of operators (o), sample size of parts (p), and replicate (r) are used. In this paper we propose how to determine the optimal combination of number of operators (o), sample size of parts (p), and replicates (r) considering measurement time and cost by statistical method.

• Explosives and Blasting
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• v.10 no.4
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• pp.19-50
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• 1992

This Study is Concerned about the Gage Controled analysis in Tunneling. Gage Control was to analysis made by recording paper such as Convergence meter, Inclinometer and extensometer etc.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.975-982
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• 2005

The purpose of the Gage R&R study is to determine whether a measurement system is adequate for monitoring a process. If the measurement system variation is small relative to the process variation, then the measurement system is deemed 'adequate'. The sources of variation associated with the measurement system are compared using an analysis of variance (ANOVA) model, in general. A typical ANOVA model used in a standard Gage R&R study is the two-factor random effect model. Then, the ANOVA partitions the total variation into three categories: repeatability, reproducibility, part variation. However, if the process variation possesses the between group variation, within group variation, and within-part variation, these variations can cause the measurement system evaluation to provide misleading results. That is, in the standard Gage R&R study these variations affect the estimate of repeatability, reproducibility, or both. This paper presents a four-factor nested factorial ANOVA model which explicitly considers these variations for the Gage R&R study. The variance component estimates are derived by setting the EMS equations equal to the corresponding mean square from the ANOVA table and solving. And the proposed model is compared with the standard Gage R&R model.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.155-160
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• 2002

A new fabrication method of FBG sensor with gage length shorter than 10 mm is introduced using the reflection prism with special coating on the surface. It is verified that the bandwidth of FBG sensor increases exponentially as the gage length of it decreases. The transverse stress and strain gradient induced by local stress concentration which occurs during curing has an influence on the FBG sensor with gage length of 2 mm less than that of 10 mm.