• The Korean Journal of Applied Statistics
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• v.35 no.3
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• pp.335-346
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• 2022

Profile control chart aims to detect a change in the functional relationship of multivariate characteristics in the statistical process control. In monitoring two variables, a linear profile is of interest composed of the intercept and slope of one variable (response variable) against the other (explanatory variable). The previous studies on monitoring of the linear profile mostly assume that the explanatory variables are the same for all profiles. However, there are also cases where they vary depending on profiles. This paper intends to extend the monitoring method to where explanatory variables are different for each profile. We compare the new method's performance through simulation and apply it to monitoring a network intrusion using NSL-KDD data.

• Fashion & Textile Research Journal
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• v.24 no.2
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• pp.195-205
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• 2022

This study examines the image management behavior according to self-monitoring, self-objectification of profile-based SNS users. Questionnaires were administered to 313 SNS users including both men and women in their 20s to 30s. The SPSS 25.0 package was utilized for data analysis, which included frequency analysis, factor analysis, Cronbach's ?, t-test, and regression analysis. The study analyzed self-monitoring in 2 groups (high, low), self-objectification for 2 factors (body surveillance, body shame), and image management behavior for 5 factors (fashion oriented, instrumentality, conformity, ostentation, interpersonal disposition). The results revealed: first, self-monitoring groups exhibited significant differences in self-objectification. The higher self-monitoring group was more influenced by body surveillance and body shame compared to the low self-monitoring group. Second, self-objectification had a positive influence on all the factors of image management behavior. Especially, body surveillance demonstrated a high influence on instrumentality and body shame showed a high influence on ostentation. Third, the self-monitoring groups showed significant differences in all the factors of image management behavior. The higher self-monitoring group demonstrated more influence of image management behavior compared to the low self-monitoring group. These results provide useful information in understanding the influence of social media on users' psychological attitude and consciousness toward their body and image management behavior.

• Journal of Korean Society for Quality Management
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• v.43 no.4
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• pp.573-588
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• 2015

Purpose: For improving result of estimated remaining useful life in Prognostics and Health Management (PHM), a system which is able to consider a lot of environment and load data is required. Method: A load profile monitoring system was presented based on cloud computing for gathering and processing raw data which is included environment and load data. Result: Users can access results of load profile information on the Internet. The developed system provides information which consists of distribution of load data, basic statistics, etc. Conclusion: We developed the load profile monitoring system for considering much environment and load data. This system has advantages such as improving accessibility through smart device, reducing cost, and covering various conditions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.815-816
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• 2007

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.6
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• pp.737-745
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• 2008

Recent developments of process and measurement technology bring much interest to the online monitoring of process operations such as milling, grinding, broaching, etc. The objective of online monitoring systems is to detect process changes as early as possible. This is helpful in protecting facilities against unexpected failures and then preventing unnecessary loss. This paper investigates, when the process monitoring data are obtained as a profile, the monitoring performances of a statistical $T^2$-statistic and a feedforward neural network by using a wavelet transform. Numerical experiments using cutting force data presented by Axinte show that the proposed wavelet based $T^2$-test has an acceptable power in detecting profile changes. However, its operating characteristic is very sensitive to autocorrelation. On the contrary, compared with $T^2$-test, the neural network has more stable performance in the presence of autocorrelation. This indicates that an adaptive feature to analyze noises should be incorporated into the wavelet based $T^2$-test.

• Korean Journal of Childcare and Education
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• v.17 no.3
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• pp.65-87
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• 2021

Objective: This study aimed to examine the effects of maternal monitoring, shared activities with children, maternal education-oriented behavior, and allowing children to own smart-phones on smart media usage patterns based on smart-phone usage time and purposes among elementary school children. Methods: The participants were 1,315 second-grade elementary school children from the 9th wave of PSKC. Latent profile analysis and the three-step estimation approach were used to examine the determinants of the latent profile and the effects of maternal parenting on the profile. Results: Four latent profiles were identified: 'High-level usage & Entertaining oriented,' 'Moderate-level usage & Social/entertaining oriented,' 'Moderate-level usage & Learning oriented,' and 'Low-level usage.' Additionally, results showed that each profile can be predicted by maternal monitoring, education-oriented behavior, and permitting children to own smart-phones. Conclusion/Implications: Our outcomes suggested that it would be necessary to understand the smart media usage patterns of elementary school children, considering both the amount of time spent with smart media and purposes of uses. Further, it is helpful for mothers to monitor children's daily activities, support their educational activities, and take the role of gatekeeper for smart media as a way of appropriate guidance for their children's use of smart media.

• Journal of Welding and Joining
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• v.33 no.4
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• pp.24-29
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• 2015

The current waveform was analysed to monitor the weld quality in real time process. The acquired current waveform was discretely analysed for the top and bottom limits of peaks as well as the pulse frequency measurement. Fast Fourier Transform was implemented in the program to monitor the pulse frequency in real time. The developed algorithm or program was tested for the validation purpose. The cross-section of weld profile was compared to the current waveform profile to correlate the monitored signal and the actual parts. Pulse frequency was also used as auxiliary tool for the quality monitoring. Based on the results, it was possible to evaluate the quality of welding by measure the current waveform profile and frequency measurement.

• Industrial Engineering and Management Systems
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• v.15 no.4
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• pp.432-445
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• 2016

A random profile is the result of a process, the output of which is a function instead of a scalar or vector quantity. In the nature of these objects, two main dimensions of "functionality" and "randomness" can be recognized. Valuable researches have been conducted to present control charts for monitoring such processes in which a regression approach has been applied by focusing on "randomness" of profiles. Performing other statistical techniques such as hypothesis testing for different parameters, comparing parameters of two populations, ANOVA, DOE, etc. has been postponed thus far, because the "functional" nature of profiles is ignored. In this paper, first, some needed theorems are proven with an applied approach, so that be understandable for an engineer which is unfamiliar with advanced mathematical analysis. Then, as an application of that, a statistical test is designed for mean of continuous random profiles. Finally, using experimental operating characteristic curves obtained in computer simulation, it is demonstrated that the presented tests are properly able to recognize deviations in the null hypothesis.

• KEPCO Journal on Electric Power and Energy
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• v.8 no.2
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• pp.127-135
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• 2022

With the advent of high technologies such as the 4th Industrial Revolution and artificial intelligence and big data, efforts are being made to solve urban problems and improve the quality of life by applying new technologies in the smart city field. In addition, as carbon neutrality has emerged as an important issue due to global warming, smart city energy platform technologies such as urban energy management, efficiency improvement, and carbon reduction are in the spotlight. In order to effectively manage urban energy, energy resource information such as electricity, water, gas, hot water, heating, etc. must be collected from the management system of various energy utilities and managed on the central platform. The centrally integrated data is delivered to external city management systems that require city energy information through an energy platform. This study developed a CIM profile for smart city energy monitoring required to provide energy data to external systems. Electric data model were designed using the CIM class of IEC 61970, and water, gas, and heat data model were designed in compliance with the UML-based design ideas of IEC 61970.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.5
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• pp.37-45
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• 2003

To investigate the influence of the design and operating parameters of the headbox on hydrodynamics, a pilot headbox system and pressure monitoring apparatus were constructed. The pilot headbox system consisted of a circulating water reservoir, centrifugal pump, distributor, turbulence generator and slice. The distributor was designed to function as a pressure attenuator. Flow rate to the headbox and MD and CD velocity profiles in the slice zone were monitored using an ultrasonic flowmeter and Pitot tubes, respectively. As the distance from the step diffusor increased, evener CD velocity profile was observed. Wall effect increased with the increase of the velocity. Flow stability in the headbox was evaluated by injecting a dye at the outlet of the distributor. Application of theoretical analysis based on CFD in designing headboxes is briefly discussed.