• The Journal of Asian Finance, Economics and Business
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• v.5 no.3
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• pp.19-29
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• 2018

This research examined the alternatives of Jensen's alpha (α) estimation models in the Capital Asset Pricing Model, discussed by Treynor (1961), Sharpe (1964), and Lintner (1965), using the robust maximum likelihood type m-estimator (MM estimator) and Bayes estimator with conjugate prior. According to finance literature and practices, alpha has often been estimated using ordinary least square (OLS) regression method and monthly return data set. A sample of 50 securities is randomly selected from the list of the S&P 500 index. Their daily and monthly returns were collected over a period of the last five years. This research showed that the robust MM estimator performed well better than the OLS and Bayes estimators in terms of efficiency. The Bayes estimator did not perform better than the OLS estimator as expected. Interestingly, we also found that daily return data set would give more accurate alpha estimation than monthly return data set in all three MM, OLS, and Bayes estimators. We also proposed an alternative market efficiency test with the hypothesis testing Ho: α = 0 and was able to prove the S&P 500 index is efficient, but not perfect. More important, those findings above are checked with and validated by Jackknife resampling results.

• Journal of Korea Multimedia Society
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• v.18 no.2
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• pp.207-217
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• 2015

A multi-cup electric cupping system (MECS) was proposed, based on the ancient cupping method. MECS consisted of several cups that could be used simultaneously to treat 85 lumbago patients. Each cup was equipped with its own pump and pressure-monitoring system. The vacuum pressure of the cups was controlled using fuzzy logic. Through automated control of the vacuum pressure, long-term relief of muscle tightness was achieved. To develop a scientific foundation for this alternative treatment, we compared the Oswestry Disability Index (ODI) scores from conventional basic cupping to the ODI scores for our proposed MECS. The ODI scores using MECS decreased from $11.71{\pm}1.61$ before treatment to $4.81{\pm}1.48$ and $1.87{\pm}1.61$ after three and five treatments, respectively. The improvement rate in the ODI scores using MECS after three treatments was higher than that achieved by basic cupping. These results, combined with the convenience offered by enhanced information technology and fuzzy logic capabilities, should increase the efficiency of this device, and facilitate the opportunity to further explore the potential of Oriental medical practices.

• Safety and Health at Work
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• v.5 no.3
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• pp.152-157
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• 2014

Background: As health care workers face a wide range of psychosocial stressors, they are at a high risk of developing burnout syndrome, which in turn may affect hospital outcomes such as the quality and safety of provided care. The purpose of the present study was to investigate the moderating effect of job control on the relationship between workload and burnout. Methods: A total of 352 hospital workers from five Italian public hospitals completed a self-administered questionnaire that was used to measure exhaustion, cynicism, job control, and workload. Data were collected in 2013. Results: In contrast to previous studies, the results of this study supported the moderation effect of job control on the relationship between workload and exhaustion. Furthermore, the results found support for the sequential link from exhaustion to cynicism. Conclusion: This study showed the importance for hospital managers to carry out management practices that promote job control and provide employees with job resources, in order to reduce the burnout risk.

• Journal of Korean society of Dental Hygiene
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• v.24 no.4
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• pp.333-341
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• 2024

Objectives: This study aimed to identify the key components and tools for Comprehensive Dental Hygiene Care (CDHC) among dental hygienists and provide foundational data for widespread implementation in dental institutions. Methods: A third Delphi survey involving experts derived the CDHC components and materials. Dental hygienists' characteristics and the CDHC application status were analyzed for frequency. The perceived need for and willingness to apply the CDHC components based on general characteristics were assessed using t-tests. Results: The results of the Delphi survey identified the following CDHC components: 11 for medical history; three, dental history; five, oral hygiene practices; seven, dental conditions; three, occlusion conditions; six, periodontal conditions; and, three, other examinations. Planning included 3 items for healthy gums and 4 for gingivitis and mild periodontitis. Evaluation included 7 items for mild periodontitis, 5 for patient education, and totally 27 CDHC-related materials. Dental hygienists' needs and willingness varied, with higher levels among those in clinics, university graduates, those in counseling or managerial roles, team leaders or those at higher positions, and those with >6 years of experience (p<0.05). Conclusions: The Delphi survey identified the CDHC clinical application process, confirming the strong desire of dental hygienists to apply it in practice.

• Journal of Biosystems Engineering
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• v.33 no.5
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• pp.355-361
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• 2008

As agricultural machinery has become larger and tillage practices have changed in recent decades, compaction as a result of wheel traffic and tillage has caused increasing concern. If strategies to manage compaction, such as deep tillage, could be applied only where needed, economic and environmental benefits would result. For such site-specific compaction management to occur, compacted areas within fields must be efficiently sensed and mapped. We previously developed an on-the-go soil strength profile sensor (SSPS) for this purpose. The SSPS measures within-field variability in soil strength at five soil depths up to 50 cm. Determining the variability structure of SSPS data is needed for site-specific field management since the variability structure determines the required intensity of data collection and is related to the delineation of compaction management zones. In this paper, soil bin data were analyzed by a spectral analysis technique to determine the variability structure of the SSPS data, and to investigate causes and implications of this variability. In the soil bin, we observed a repeating pattern due to soil fracture with an approximate 12- to 19-cm period, especially at the 10-cm depth, possibly due to cyclic development of soil fracture on this interval. These findings will facilitate interpretation of soil strength data and enhance application of the SSPS.

• KIEAE Journal
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• v.14 no.6
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• pp.53-58
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• 2014

Residental photovoltaic power system achieved remarkable results in distribution and activation through 'One Million Green Homes Program' led by the government. However, system maintenance and management after installation are relative unsatisfactory. Thus, problems, such as malfunctioning, decrease in efficiency, breakage, etc, are occurring in succession which means that expensive facilities are not used effectively. This study attempted to propose a more preferred alternative to the photovoltaic power system currently applied and installed to the housing by investigating and analyzing the said system, identifying management practices, and deriving problems. For this study, 48 houses equipped with photovoltaic systems in J City were chosen and they were analyzed after preliminary research and field investigation. The results revealed that most of the surveyed systems in J City are still in fairly good conditions. But the instruction and information regarding the appropriate operational management of those surveyed systems have not been delivered to the owner. Therefore, promotion education and related manual deployment should be done by the contractor. In terms of installation, inadequate system location and some warranty services are required to be improved, which are usually caused by a lack of careful planning and construction. In addition, the follow-up management needs to be provided about five years later after installation considering system deterioration.

• The Korean Journal of Archival Studies
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• no.7
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• pp.3-35
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• 2003

The aim of this study is to discuss the significance of standards in general as well as that of records management in particular. It also analyzes the current state of standardization efforts that will directly and indirectly affect records management practices. It begins with introducing definitions of standards and the rationale behind the expensive and cumbersome process of standardization. Also covered are major standard-setting organizations at different levels such as international and national level and various types of standards created or endorsed by these organizations. Throughout the study, main focus is given to standards and standardization endeavors in records management. Until recently, standardization activities have been mainly concentrated on manufacturing industry. Consequently, standards regarding records management are not sufficient enough to satisfy organizational and professional needs. Even ISO/TC 46/ SC 11, which is in charge of standardization in records management at the international level, has just published one standard, ISO 15489 : 2001 and newly proposed five standards in 2002. Awareness of the current state calls for active participation of records managers to the standard-related activities as discussed in this study. It is also asked to keep up with the global movement by establishing standards tailored to Korean situations as well as by actively participating In international standardization activities In order to take an initiative at the international level.

• Ocean Systems Engineering
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• v.12 no.3
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• pp.267-284
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• 2022

A subsea pipeline designed across active shipping lane prones to failure against external interferences such as anchorage activities, hence risk assessment is essential. It requires quantifying the geometric probability derived from ship traffic distribution based on Automatic Identification System (AIS) data. The actual probability density function from historical vessel traffic data is ideal, as for rapid assessment, conceptual study, when the AIS data is scarce or when the local vessels traffic are not utilised with AIS. Recommended practices suggest the probability distribution is assumed as a single peak Gaussian. This study compares several fitted Gaussian distributions and Monte Carlo simulation based on actual ship traffic data in main ship direction in an active shipping lane across a subsea pipeline. The results shows that a Gaussian distribution with five peaks is required to represent the ship traffic data, providing an error of 0.23%, while a single peak Gaussian distribution and the Monte Carlo simulation with one hundred million realisation provide an error of 1.32% and 0.79% respectively. Thus, it can be concluded that the multi-peak Gaussian distribution can represent the actual ship traffic distribution in the main direction, but it is less representative for ship traffic distribution in other direction. The geometric probability is utilised in a quantitative risk assessment (QRA) for subsea pipeline against vessel anchor dropping and dragging and vessel sinking.

• Journal of the Korean Society for information Management
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• v.21 no.4 s.54
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• pp.89-107
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• 2004

This study analyzes the present conditions and operations of digital information rooms in the five selected university libraries located in Daegu and Kyoungpook area, with a special regard to the personnel, size of the room, facilities, collections, user instructions and public relations, and related tasks being done. It concludes with some suggestions and recommendations to improve the existing practices and the works in the room based on the result from this study.

• Korean Journal of Organic Agriculture
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• v.27 no.3
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• pp.247-269
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• 2019

Although food related lifestyle has been widely discussed over the last ten years, the majority of research on food related lifestyle has been only conducted in terms of a variable-centered approach. But, recently there is a growing body of research on food related lifestyle profiles over the last three years from the view of a person-centered approach. This study conducted both a cluster analysis and a latent profile analysis (LPA) to identify the patterns of potential food related lifestyle customer profiles based on the five components on the sample of customer, who bought organic products (n=509). The results of each statistical analysis showed both quantitatively and qualitatively different types of food related lifestyle customer profiles even though there were similar types of profiles identified in common between these two analyses. These various profiles were then compared with customer's level of buying behaviors (e.g., buying attitude and buying intentions). Results showed that food related lifestyle profiles with respect to the high level of interesting in dietary life in terms of health and safety are associated with the higher level of buying behaviors. Based on the results, implications for food related lifestyle literature, practices and future research are discussed.