• Industrial Engineering and Management Systems
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• v.4 no.1
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• pp.75-81
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• 2005

Borror et al. discussed the EWMA(Exponentially Weighted Moving Average) chart to monitor the count of defects which follows the Poisson distribution, referred to the $EWMA_c$ chart, as an alternative Shewhart c chart. In the $EWMA_c$ chart, the Markov chain approach is used to calculate the ARL (Average Run Length). On the other hand, in order to monitor the process fraction defectives P in high-yield processes, Xie et al. presented the CCC(Cumulative Count of Conforming)-r chart of which quality characteristic is the cumulative count of conforming item inspected until observing $r({\geq}2)$ nonconforming items. Furthermore, Ohta and Kusukawa presented the $CS(Confirmation Sample)_{CCC-r}$ chart as an alternative of the CCC-r chart. As a more superior chart in high-yield processes, in this paper we present an $EWMA_{CCC-r}$ chart to detect more sensitively small or moderate shifts in P than the $CS_{CCC-r}$ chart. The proposed $EWMA_{CCC-r}$ chart can be constructed by applying the designing method of the $EWMA_C$ chart to the CCC-r chart. ANOS(Average Number of Observations to Signal) of the proposed chart is compared with that of the $CS_{CCC-r}$ chart through computer simulation. It is demonstrated from numerical examples that the performance of proposed chart is more superior to the $CS_{CCC-r}$ chart.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.5
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• pp.267-275
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• 2022

Using a nonconforming mesh in enrichment methods results in several numerical issues induced by discontinuities and singularities found within the solution spaces, including the computational overhead during integration. In this study, we present a novel enrichment technique based on the selective expansion technique of moment fitting (Düster and Allix, 2020). In particular, two modifications are proposed to address the inefficiency during the integration process. First, a feedforward artificial neural network is introduced to correlate the implicit functions and integration moments. Through numerical examples, it is shown that the efficiency of the method is greatly improved when compared with existing expansion techniques, whereas the solution accuracy is maintained. Additionally, the finite element and domain representation grids are separated, which in turn improves the solution accuracy even for coarse mesh conditions.

• Journal of Korean Society for Quality Management
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• v.51 no.4
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• pp.619-632
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• 2023

Purpose: The main function of INS (Inertial Navigation System) is to measure the position of an armed vehicle and its performance is confirmed through the positioning accuracy test of Korean Defense Standards (KDS). The current standards, however, do not provide clear test methods and the conditions for performing positioning accuracy tests. Accordingly, the purpose of this study is to develop a new method for positioning accuracy test which would be effective. Methods: In this study, a new INS positioning accuracy test method is suggested based on the analysis of test data collected through a statistical experiment known as central composite design. For the positioning accuracy experiment of K105A1, a self-propelled artillery, two factors of driving velocity and driving distance are considered. Results: Based on the analysis of experimental data, a regression model for the positioning error is fitted and the positioning accuracy test of INS is so developed to maximize the positioning error. The standard proximity rate is used as an additional test criterion to evaluate the performance level of INS. Conclusion: The proposed new positioning accuracy test for INS has the advantage of finding the nonconforming items effectively. It is also expected to be utilized for the other similar INS positioning accuracy tests.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.12
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• pp.429-460
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• 1999

The letter of credit is quintessentially international. In the absence of international legal system, a private system based on banking practices has evolved, commanding the adherence of the international letter of credit community and providing the foundation of th reputation of this instrument. To maintain this international system, it is vital that international standard banking practice should not be subject to local interpretations that misconstrue or distort it. The UCP is a formulation of international standard banking practice. It is neither positive law nor a "contract term" in any traditional sense and its interpretation must be consonant with its character as a living repositary of international understanding in this field. As a result, the interpretation and application of specific articles of the UCP must be consistent with its evolving character and history and with the principles upon which sound letter of credit practice is predicated. This study, especially, focuses on article 13 and article 14 of the UCP500. Article 13(b) of UCP500 stipulates that banks will have a reasonable time, not to exceed seven days, to examine documents to determine whether they comply facially with the terms of the credit. The seven-day provision is not designed as a safe harbor, because the rule requires the issuer to act within a reasonable time. But, by virtue of the deletion of the preclusion rule in the document examination article in UCP500, however, seven days may evolve as something of a safe harbor, especially for banks that engage in strategic behavior. True, under UCP500 banks are supposed to examine documents within a reasonable time, but there are no consequences in UCP500 for a bank's violation of that duty. It is only in the next provision. Courts might read the preclusion more broadly than the literal reading mentioned here or might fashion a common-law preclusion rule that does not require a showing of detriment. Absent that kind of development, the change in the preclusion rule could have adverse effects on the beneficiary. The penalty, strict estoppel or strict preclusion, under UCP500 and 95UCC differs from the classic estoppel. The classic estoppel rule requires a beneficiary to show three elements. 1. conduct on the part of the issuer that leads the beneficiary to believe that nonconforming documents do conform; 2. reasonable reliance by the beneficiary; and 3. detriment from that reliance. But stict preclusion rule needs not detrimental reliance. This strict estoppel rule is quite strict, and some see it as a fitting pro-beneficiary rule to counterbalance the usually pro-issuer rule of strict compliance.

• Korean Journal of Construction Engineering and Management
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• v.17 no.1
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• pp.110-118
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• 2016

Construction projects are getting more complex and larger-sized with a high economic growth rate and development of new construction technologies. In addition, interests and demands on standards of construction quality are further increasing. This trend requires more systematic and a higher level of construction quality management. While the government has strengthened the regulations for quality assurance, many quality problems have repeatedly occurred mainly due to lack of recognition for quality management and quality control systems. To address this issue, this paper aims to suggest quality management improvement scheme through analyzing 3,443 nonconforming items identified during inspection of 393 construction sites from March 2012 to October 2014. The quality management improvement scheme suggested in this research is expected to prevent quality problems and defects and thus improve construction performances.

• Journal of Convergence for Information Technology
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• v.10 no.3
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• pp.115-125
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• 2020

Problem-Based Learning is the most commonly used teaching method in the field of education as the demand for talented people with creative problem-solving abilities has increased in recent society. In this study, we developed a tool that can simply and regularly measure the learning effects of applying Problem-Based Learning on the classroom. Twenty-two preliminary items for the development were constructed by gathering expert opinions about items collected in existing research of Problem-Based Learning effects measurement. Using this preliminary items, data were collected from 124 students who took the subject-based study. And the validity and reliability were verified through Rash analysis. 11 of 124 students and 1 of 22 items were found to nonconforming and excluded. In addition, the optimal scale for the configuration of this tool was found to be a four-point scale, and the reliability of separation on the subject and the item was found to be excellent. We hope that the assessment tools of Problem-Based Learning effectiveness developed in this study will be actively used to measure learning effectiveness and manage the quality of education.

• The Journal of Bigdata
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• v.5 no.2
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• pp.53-67
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• 2020

This study employees a supervised learning prediction model to detect nonconformity in advance of processed food manufacturing and processing businesses. The study was conducted according to the standard procedure of machine learning, such as definition of objective function, data preprocessing and feature engineering and model selection and evaluation. The dependent variable was set as the number of supervised inspection detections over the past five years from 2014 to 2018, and the objective function was to maximize the probability of detecting the nonconforming companies. The data was preprocessed by reflecting not only basic attributes such as revenues, operating duration, number of employees, but also the inspections track records and extraneous climate data. After applying the feature variable extraction method, the machine learning algorithm was applied to the data by deriving the company's risk, item risk, environmental risk, and past violation history as feature variables that affect the determination of nonconformity. The f1-score of the decision tree, one of ensemble models, was much higher than those of other models. Based on the results of this study, it is expected that the official food control for food safety management will be enhanced and geared into the data-evidence based management as well as scientific administrative system.

• Journal of Intelligence and Information Systems
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• v.29 no.1
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• pp.307-325
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• 2023

Due to the prolonged COVID-19 pandemic, the frequency of people who are tired of living indoors visiting nearby mountains and national parks to relieve depression and lethargy has exploded. There is a place where thousands of people who came out of nature stop walking and breathe and rest, that is the mineral spring. Even in mountains or national parks, there are about 600 mineral springs that can be found occasionally in neighboring parks or trails in the metropolitan area. However, due to irregular and manual water quality tests, people drink mineral water without knowing the test results in real time. Therefore, in this study, we intend to develop a model that can predict the quality of the spring water in real time by exploring the factors affecting the quality of the spring water and collecting data scattered in various places. After limiting the regions to Seoul and Gyeonggi-do due to the limitations of data collection, we obtained data on water quality tests from 2015 to 2020 for about 300 mineral springs in 18 cities where data management is well performed. A total of 10 factors were finally selected after two rounds of review among various factors that are considered to affect the suitability of the mineral spring water quality. Using AutoML, an automated machine learning technology that has recently been attracting attention, we derived the top 5 models based on prediction performance among about 20 machine learning methods. Among them, the catboost model has the highest performance with a prediction classification accuracy of 75.26%. In addition, as a result of examining the absolute influence of the variables used in the analysis through the SHAP method on the prediction, the most important factor was whether or not a water quality test was judged nonconforming in the previous water quality test. It was confirmed that the temperature on the day of the inspection and the altitude of the mineral spring had an influence on whether the water quality was unsuitable.