• Journal of the Korean Mathematical Society
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• v.46 no.3
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• pp.463-473
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• 2009

Two $C^1$-mappings, whose domain is a connected compact $C^1$-Banach manifold modelled over a Banach space X over $\mathbb{K}=\mathbb{R}$ or $\mathbb{C}$ and whose range is a Banach space Y over $\mathbb{K}$, are introduced. Sufficient conditions are given to assert they share only a value. The proof of the result, which is based upon continuation methods, is constructive.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.10a
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• pp.36-43
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• 1998

The purpose of study is to propose numerical assessment methods of lateral deformation shape under lateral loads for regular high-rise buildings. The normalized 1st mode shape is used to assess lateral deformation shape. The assessment method are mass participation factor, representative value by RMS, the mean value, median of the nomalized 1st mode shape. These methods are able to know a fundamental lateral deformation shape of the building and effects of interactive systems numerically. Generally the characteristics of normalized 1st mode shape for various models coincide with numerical assessment results.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.14 no.24
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• pp.187-192
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• 1991

We consider a filling process problem on a production line. Up to present this problem have examined by 100% inspection. Thus a target value is determined which takes into account the regular selling prices, the reprocess cost, the excess quality cost and the process variability and so on. However, in this paper we propose a solution under specified sampling plan when the inspection is nondestructive.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.199-211
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• 2021

This study suggests an alternative for solving quality-of-life problems of an aging workforce by seeking ways to utilize an aging workforce in corporations and society. This research empirically analyzed data from the 6th panel data of aging. Study results are as follows. First, it was confirmed that job satisfaction of aging manpower plays a mediating role in the relationship between quality of life and the job characteristics of an aging workforce. Second, it was found that the wage level of regular workers had a significant effect on job satisfaction and quality of life, and the job satisfaction of regular workers was mediated between wage level and quality of life. On the other hand, the wage level of non-regular workers did not have any effect on job satisfaction and quality of life. The results of this study suggest the necessity for companies to recognize the use of an aging workforce to improve social value. Furthermore, our results provide implications for domestic firms and government policymakers on how to use a domestic aging workforce and how to utilize regular and non-regular workers.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.2
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• pp.138-148
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• 2017

Objectives: Sleep quality is directly related to the health, quality of life and working capacity and is affected by age, gender, exercise, life habits. Gender dissimilarities in sleep quality are acknowledged. However, the gender difference in the quality of sleep in shift workers was not well known. Our aim was to study the less known gender differences in the quality of sleep of shift workers. Methods: 1,008 study subjects aged between 21 and 57 years among these, 637(525 male and 112 female workers) were daytime workers and 371(253 males and 118 female workers) were shift workers. Sleep quality was measured by self-report through the Pittsburg Sleep Quality Index(PSQI) and fatigue was measured by using the Chalder Fatigue Scale(CFS). All data was analyzed using SPSS version 19.0 program. The study was approved by the Institutional Review Board of the Occupational Safety and Health Research Institute. Results: Overall, sleep quality was found to be worse in shift workers than in daytime workers and in female than in male. Fatigue in shift female workers was significantly higher than in daytime female workers and shift male workers. In Spearman correlation analysis results, fatigue were significantly associated with gender, drink habit, regular exercise, working hours and sleep quality. With group male workers as the reference, the odds ratio(OR) for having a CFS was 2.115(${\beta}$ value=0.749, p<0.01), and subjective sleep quality, sleep latency, daytime dysfunction and PSQI were 1.541(${\beta}$ value=0.432, p<0.05), 2.297(${\beta}$ value=0.831, p<0.001), 1.798(${\beta}$ value=0.587, p<0.01) and 2.224(${\beta}$ value=0.799, p<0.01), respectively. Conclusions: Shift work played an important role in lowering the quality of sleep, and the effect was more pronounced in female workers than in male workers. Sleep quality was related to fatigue, especially sleep quality, sleep duration, sleep disturbances and daytime dysfunction were significantly related. Therefore, to improve fatigue and sleep quality of shift worker, it is necessary to improve healthy habits such as regular exercise, smoking cessation, and limited drinking. In particular, it is urgent to develop and implement a regular exercise program to reduce fatigue and improve the quality of sleep in workplace.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.279-288
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• 2009

The purposes of this study were to understand the differences of general characteristics, to compare understanding level of the organization cultures, and to develop more good management methods between outsourcing workers and regular workers in hospitals. Major results of this study were as follows: First, regular workers had higher level than outsourcing workers in major understanding on job satisfaction and organization cultures(pride of their jobs, recognition level of job performance ability, satisfaction on ordering method. etc.). Second, the results showed that the level of job performances related with effective management of the factors in job satisfaction and involvement. Third, through multiple regression analysis to understand factors on job satisfaction and involvement, we understood that regular workers were effected by vision performance of hospital and their value view-point, and outsourcing workers were influenced by recognition levels and education levels of hospital vision, Therefore, to maximize level of job satisfaction and involvement. we have interest in development of education program for outsourcing workers, and selection of adequate persons in hospital culture.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.2
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• pp.71-79
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• 2010

Thanks to the great development of technology in radiation, we are now able to reduce radiation exposure to the patients, and the radiographer and expenses in medical sector. We are also trying to produce ideal images which maintain useful information. These kinds of effort are increasing over the world. For that reason, we should get images which include necessary data of patients. Then it also can help to reduce radiation exposure to the patients. Therefore, we need to know the problems that cause a falling off in image's quality and check on generator in case of their electronic and mechanical errors. And moreover, we should anticipate the possibility of devices errors and prevent them with regular quality control. This investigation was conducted in medical institutions, institute of educations and hospitals. They are all in Seongnam-City. We used PMX-III, kVp meter to implement kVp test, mR / mAs output test, light fiel / beam alignment test, Reproducibility of exposure dose, half value layer test, reproducibility of exposure time test. in the case of hospitals, they perceive the importance of regular quality control and organize the regular quality control team so they can be satisfied with the error standard in most experiments. On the other hand, when it comes to medical institutions and institute of educations, they perceive the importance of regular quality control less than hospitals do. Radiographer need to understand the importance of regular quality control and practice it so they can get the fine ideal image with the lower dose to the patient.

• Culinary science and hospitality research
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• v.19 no.5
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• pp.234-248
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• 2013

This study aimed to examine the roles of perceived convenience and usefulness of restaurant customers' revisit intention. To achieve the purpose of this study, it reviewed the theoretical background about perceived convenience, perceived usefulness and revisit intention and conducted an empirical analysis of them. For the empirical analysis, a questionnaire was given to a total of 228 regular restaurant customers at Busan area. The results were as follows. 1) The regular restaurant customers' perceived convenience and perceived usefulness had a significant effect on their revisit intention. 2) The regular customers' perceived convenience had an effect on their perceived usefulness. 3) Time elements and experience of visiting a restaurant had an effect on the perceived convenience. 4) Utilitarian values and hedonic values had an effect on the perceived usefulness.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.3
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• pp.175-179
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• 2023

This paper analyzes the vibration characteristics within the cargo compartment of a three-wheeled cargo bike when used on both regular roads and dedicated bicycle lanes. When cargo is loaded into the cargo compartment of a cargo bike and driven on the road, the shocks and vibrations transmitted from the ground can potentially affect the transported goods and even lead to product damage. As the vibration characteristics applied to the cargo compartment may vary depending on the condition of the road, vibration sensors were attached to the cargo bike's cargo compartment for data collection during operation on different road types. According to KS T ISO 13355 standards, the cargo bike can withstand vibrations within the range of 10 Hz to 60 Hz when operating on both bicycle lanes and regular roads. However, it is observed that there are peaks exceeding the profile in the frequency range of 3-6 Hz. In the 70-200 Hz range, the profile is exceeded on both regular roads and bicycle lanes, with a tendency for higher exceedance on bicycle lanes. The Grms value within the frequency range of KS T ISO 13355 is 5.926 m/s² (0.604 Grms). When operating on bicycle lanes with cargo, the Peak envelope optimization PSD value is 6.553 Grms, while on bicycle lanes, it is 7.708 Grms, indicating a difference of at least tenfold.

• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.457-473
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• 2005

In each step of the quasi-minimal residual (QMR) method which uses a look-ahead variant of the nonsymmetric Lanczos process to generate basis vectors for the Krylov subspaces induced by A, it is necessary to decide whether to construct the Lanczos vectors $v_{n+l}\;and\;w{n+l}$ as regular or inner vectors. For a regular step it is necessary that $D_k\;=\;W^{T}_{k}V_{k}$ is nonsingular. Therefore, in the floating-point arithmetic, the smallest singular value of matrix $D_k$, ${\sigma}_min(D_k)$, is computed and an inner step is performed if $\sigma_{min}(D_k)<{\epsilon}$, where $\epsilon$ is a suitably chosen tolerance. In practice it is absolutely impossible to choose correctly the value of the tolerance $\epsilon$. The subject of this paper is to show how discrete stochastic arithmetic remedies the problem of this tolerance, as well as the problem of the other tolerances which are needed in the other checks of the QMR method with the estimation of the accuracy of some intermediate results. Numerical examples are used to show the good numerical properties.