• International Journal of Quality Innovation
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• v.1 no.1
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• pp.97-105
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• 2000

In this paper, a two-section method for measuring is introduced and the variation sources of measurement process are analysed. Measuring is a special process in general process. Various variation source must be firstly decomposed so that the statistical distribution law of measuring process can be established, and then implement monitoring control of the measuring process. A special method to obtain the measuring variation is discussed, and a monitoring control technique for measuring process is studied based statistical distribution. Towards the end, we briefly introduce software design for the analysis and control of a measurement process.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.2
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• pp.182-192
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• 2014

Objectives: The aim of this study is to analyze the current status of possession of measurement and analytical instruments at work environment monitoring organizations and their relationships with human resources, including the number of professional engineers and evaluation scores resulting from evaluation programs in 2012. Materials: Data for measurement and analytical instruments were gathered by inspectors who had been assigned by the Korea Occupational Safety and Health Agency(KOSHA) and the Ministry of Employment and Labor(MoEL) during the evaluation program for 2012. Data for 11 monitoring instruments and nice pieces of analytical equipment were collected from 103 organizations. Additional data such as the type of service provides and the number of professional engineers employed were also recorded by the inspectors. Evaluation scores could be acquired from KOSHA. Results: Comprehensive Occupational Health Service Providers showed good operation quality, while University or Hospital Subsidiary and Work Environment Monitoring Organizations recorded relatively poor results. Evaluation scores correlated well with the possession of measurement instruments and human resources for each organization. High yields provided by professional engineers also showed statistically-associated contributions to evaluation scores and monitoring instrument possession. Compared with monitoring instruments, the amount of analytical equipment had little positive impact on organizations' competence. Conclusions: The evaluation results for domestic monitoring organizations revealed that human resources, possession of instruments, and the quality of employees were critical factors for operating the corporations. Each organization should give considerable effort to improving their ability to strengtheninternal quality, resulting in high-yield production for workers and employers by providing improved workplace monitoring services.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.606-611
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• 2002

Welding using lasers can be mass-produced in high speed. In the laser welding, performing real-time monitoring system of the welding quality is very important in enhancing the efficiency of welding. In this study, the plasma and molten metal which are generated during laser welding were measured using the UV sensor and IR sensors. The results of laser welding were classified into five categories such as optimal heat input, little low heat input, low heat input, partial joining due to gap mismatch, and nozzle deviation. Also, a system was formulated which uses the measured signals with a fuzzy pattern recognition method which is used to perform real-time evaluation of the welding quality and the defects which can occur in laser welding.

• Laser Solutions
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• v.3 no.2
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• pp.53-61
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• 2000

On the laser weld production line, a slight alteration of the welding condition produces many defects. The defects are monitored in real time, in order to prevent continuous occurrence of defects, reduce the loss of material, and guarantee good quality. The measurement system is produced by using three photo-diodes for detection of the plasma and spatter signal in CO$_2$ laser welding. For high speed CO$_2$ laser welding, laser tailored welded blanks for example, on-line weld quality monitoring system was developed by using fuzzy multi-feature pattern recognition. Weld qualities were classified optimal heat input, a little low heat input, low heat input, and focus misalignment, and final weld quality were classified good and bad.

• International Journal of Korean Welding Society
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• v.1 no.1
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• pp.7-12
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• 2001

Real time monitoring has become critical as the use of laser welding increases. Plasma and spatter are measured and used as the signal for estimating weld quality. The estimating algorithm was made using the fuzzy pattern recognition with the area of data that is beyond the tolerance boundary. Also, an algorithm that detects the spatter and the localized defect was created in order to kd the partially produced pit and the sudden loss of weld penetration. These algorithms were used in quality monitoring of the $CO_2$ laser tailored blank weld. Statistical program that can display the laser weld quality result and the signal transition was made for the first stage of the remote control system.

• Journal of Korean Society for Quality Management
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• v.26 no.1
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• pp.108-125
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• 1998

The EWMA(Exponentially Weighted Moving Average) has recently received a great deal of attention in the quality control literature as a process monitoring tool on the shop floor of manufacturing industires, since it is easy to plot, to interpret, and its control limits are easy to obtain. Most a, pp.ications of the EWMA for process monitoring have concentrated on the problem of detecting shifts of a process mean and a process standard deviation with ARL(Average Run Length) properties. But there may be the necessity of controlling linearity on product quality such as the correlation coefficient to the process operator. Control managers may want to protect the increase of a process correlation coefficient value, such as 0, between two variables of interest. However, there are few studies concerned on this part. Therefore, we propose EWMA models for a process correlation coefficient using two transformed statistics, T-statistic and (Fisher's) Z-statistic. We also present some results of simulation by SAS/IML and compare two models.

• Journal of Welding and Joining
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• v.1 no.2
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• pp.69-75
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• 1983

Both in-process quality control and reliability of the weld is one of the major concerns is applying friction welding. No reliable nondestructive monitoring method is available at present to determine the weld quality particularly in process of production. So that, this paper presents an experimental examination and quantitative analysis for the effects of initial acoustic emission(AE) counts on the weld strength relating to the rotating speed as a new approach which attempts finally to develop an on-line quality monitoring system design for friction welds using AE techniques. As one of the important results, it was well confirmed that the initial AE counts occurring during plastic deformation period of welding were quantitatively correlated with reliability at 95% confidence level to the joint strength of welds, tube-to-tube (SM 20 C to STS 304) and then an AE technique using the initial AE counts can be reliably applied to in-process strength monitoring of the weld.

• International Journal of Korean Welding Society
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• v.3 no.1
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• pp.45-50
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• 2003

Welding using lasers can be mass-produced in high speed. In the laser welding, performing real-time monitoring system of the welding quality is very important in enhancing the efficiency of welding. In this study, the plasma and molten metal which are generated during laser welding were measured using the UV sensor and IR sensors. The results of laser welding were classified into five categories such as optimal heat input, little low heat input, low heat input, partial joining due to gap mismatch, and nozzle deviation. Also, a system was formulated which uses the measured signals with a fuzzy pattern recognition method which is used to perform real-time evaluation of the welding quality and the defects which can occur in laser welding.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.65-66
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• 2007

• Health Policy and Management
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• v.13 no.3
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• pp.35-51
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• 2003

This study purports to develop a quality assessment tool for the process of health promotion programs at public health centers(PHC). The draft of the assessment tool developed by the literature was distributed to 242 staffs who were in charge of the health promotion programs at PHCs for evaluating the feasibility of the tool on September and October 2002. The major results of the study were as follows; The quality assessment tool developed in the study consisted of four domains: strategic planning, program management, monitoring and evaluation, and resources and information. The strategic planning dealt with the function of the planning staff and committees, community data analysis, the feasibility of the program, and the approach methods for attaining the goal of the program. The program management included the items on the qualification and power of the program staff. The monitoring and evaluation included the items on the reporting and communication among program units, and feed back after monitoring. Finally, the resources and information dealt with community networking, clients' response, and consulting activity of the staff. The validity of the tools was tested and partly supported by both formative and criterion-related methods. The assessment tools developed in this study could be used by health promotion workers in the self-evaluation of the program quality. In conclusion, the quality assessment tool developed in the study will be a good safeguard for assuring the quality of the process of health promotion programs.