• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8589-8594
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• 2016

Background: Liver cancer is one of the most common causes of death in the world. In Korea, hepatitis B virus (HBV) is a major risk factor for liver cancer but infection rates have been declining since the implementation of the national vaccination program. In this study, we examined the secular trends in liver cancer mortality to distinguish the effects of age, time period, and birth cohort. Materials and Methods: Data for the annual number of liver cancer deaths in Korean adults (30 years and older) were obtained from the Korean Statistical Information Service for the period from 1984-2013. Joinpoint regression analysis was used to study the shapes of and to detect the changes in mortality trends. Also, an age-period-cohort model was designed to study the effect of each age, period, and birth cohort on liver cancer mortality. Results: For both men and women, the age-standardized mortality rate for liver cancer increased from 1984 to 1993 and decreased thereafter. The highest liver cancer mortality rate has shifted to an older age group in recent years. Within the same birth cohort group, the mortality rate of older age groups has been higher than in the younger age groups. Age-period-cohort analysis showed an association with a high mortality rate in the older age group and in recent years, whereas a decreasing mortality rate were observed in the younger birth cohort. Conclusions: This study confirmed a decreasing trend in liver cancer mortality among Korean men and women after 1993. The trends in mortality rate may be mainly attributed to cohort effects.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.321-324
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• 2013

Background: Intra- and extrahepatic cholangiocarcinoma (CCA) is the most common cancer in Thailand, especially in the northeast region. Most extrahepatic CCA patients consult a doctor at a late stage. Surgery is still the best treatment. Objectives: The aim of this study was to evaluate survival rates and factors affecting survival in extrahepatic CCA patients following surgery at Srinagarind Hospital, Khon Kaen University, Thailand. Materials and Methods: A retrospective cohort study was conducted with 58 patients who were diagnosed and treated by surgical resection by the same surgeon at Srinagarind Hospital between 2005 and 2009. The patients were followed up until death or the end of the study (31 December, 2011). Survival rates were calculated by the Kaplan-Meier method, and the Cox proportional hazard model was used to identify independent prognostic factors. Results: The total follow-up time was 1,215 person-months, and the mortality rate was 50 per 100 person-years. The cumulative 1-, 3-, and 5-year survival rates were 62.1%, 21.7% and 10.8%, respectively. The median survival time after resection was 15 months. After adjusting for age, gender, lymph node metastasis and histological type, resection margin remained as a statistically significant prognostic factor for survival following surgery. A positive resection margin was associated with a 2.3-fold higher mortality rate than a negative margin. Conclusions: Resection margins are important prognostic factors affecting survival of extrahepatic CCA patients after surgery. A negative resection margin can reduce the mortality rate by 56%.

• The Journal of Society for e-Business Studies
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• v.14 no.1
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• pp.143-160
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• 2009

In determining the performance of OLAP database applications, the structure and the effective access methods to the underlying disk system is a significant factor. In recent years, hard disks are designed with multiple physical zones where seek times and data transfer rates vary across the zones. However, there is little consideration of multi-zone disks in previous works. Instead, they assumed a traditional disk model that comes with many simplifying assumptions such as an average seek-time and a single data transfer rate. In this paper, we propose a technique storing a set of materialized views into the multi-zoned disks in OLAP environment dealing with large sets of data. We first present the disk zoning algorithm of materialized views according to the access probabilities of each views. Also, we address the problem of storing views in the dynamic environment where data are updated continuously. Finally, through experiments, we prove the performance improvement of the proposed algorithm against the conventional methods.

• Korean Journal of Child Studies
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• v.25 no.4
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• pp.115-128
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• 2004

In this study, we examined the relationship among Multiple Intelligence constructs and the relationship among the sub-areas and analysed the development of the Multiple Intelligence according to age and gender to evaluate Korean children's Multiple Intelligence structures that teachers evaluated based on MIDAS-MYC. The subjects of the study consisted of 158 4-5 year old children (71 4-year-old group(boy 38, girl 33); 87 5-year-old group(boy 40, girl 47)) in Seoul and Gyeonggi. We found several results which are as follows. 1) Reliability on each area of intelligence in MIDAS-MYC was good. 2) The result of confirmatory factor analysis using the model of structural equation modeling was consistent with the results of other studies that children's Multiple Intelligence consists of eight intelligent areas that are independent to each other but are relative to each other. In particular, interpersonal-intrapersonal intelligence, languistic-intrapersonal intelligence, languistic-Interpersonal intelligence, and languistic-logic/math intelligence were high correlation. However, physical/motion-naturalist intelligence and musical-logic/math intelligence were low correlation. 3) Children's multiple intelligence differed according to age and sex, the 5-year-old was higher than 4-year-old and girls were higher than boys in a general way. 4) There was high correlation between the result of evaluation based on MIDAS-MYC and the result of teacher's subjective evaluation about children's Multiple Intelligence.

• Journal of the Korean Magnetics Society
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• v.23 no.6
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• pp.205-208
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• 2013

The width dependence of Delta E has been studied by impedance resonance method in Fe-rich amorphous ribbon of as received state. It can be explained by single domain model include effective magnetic field $H_{eff}$ and demagnetization factor $N_d$. Wider width ribbon's effective is smaller than narrow it. Young's modulus also smaller than narrow width. These result well agreement in calculation. It has been also studied that linear magnetic field sensor using width dependence of Delta E under the field range 0 Oe~80 Oe. The sensitivity of the sensor was found to be 95 Hz/Oe.

• Journal of Applied Reliability
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• v.16 no.3
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• pp.192-201
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• 2016

Purpose: In this paper, we propose the output model of the optimal inventory requirements of the Maintenance Float (M/F). Weapon systems were modernized and increased costs. Thus, the complexity increases with. Alternatives to achieve the goal of availability of weapon systems and to reduce life-cycle cost are required. Especially, securing spare parts is more effective than adding the amount of equipment or maintenance facilities to achieve the goal of availability and reduce life cycle costs. However, securing spare parts and repair costs are directly related, so exact requirements are needed. Methods: Three kinds of methods (Calculation method of applying the Poisson distribution, Calculation method of considering the number of CSP, and Calculation method of applying M&S program) that this paper proposed compare the influence of the availability and the amount of spare parts. Result: We calculate the cost of M/F when the operational availability is over than 80% and compare that result. The biggest cost was calculated from the Poisson distribution method. We found that requirements and unit price is the key factor that gives a significant effect. Conclusion: These three kinds of methods can be used as a basis for Maintenance Float calculation. Among them, the calculation method based on CSP is optimal replacement equipment requirements calculation method.

• Journal of Digital Convergence
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• v.16 no.4
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• pp.259-265
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• 2018

This study investigates convergent factors associated with occupational stress among General Hospital Administrative Staff(GHAS). The survey was administered to 221 staffs from 11 general hospitals located in J city from November 1st, 2016 to January 31st, 2017, using structured self-administered questionaries without respondents' personal information. The hierarchical multiple regression analysis shows the following results. The occupational stress of respondents turned out to be significantly higher in following groups: a group in which organizational justice-distributive is lower, a group in which self-esteem is lower, a group in which self-efficacy is lower. The results show explanatory power of 39.5%. The results of the study indicate that the efforts, to increase organizational justice-distributive, to increase self-esteem, to increase self- efficacy, are required to decrease the occupational stress among GHAS. These results are expected to be utilized for organizational and personnel management to reduce occupational stress in GHAS. In the following study, the research of additional factors and the analysis of structural equation model about the occupational stress among GHAS will be needed.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.151-160
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• 2017

Giving behavior can be defined to be a behavior intended to benefit the society's charity works and public works via sharing one's financial resources. The determinants of giving behavior largely consist of sociodemographic factors, such as the income, age, gender, religion, education level, residential areas, and tax deduction policy, etc. This paper considers the income level, self-esteem, and perceived responsibility toward social welfare, as the major research variables. Statistical results, based on 2014 Korean Welfare Panel data, show that the income level and self-esteem have positive influence on participation intention in charitable giving. However, welfare responsibility has negative impact on participation intention. Second, household income was the only salient, negative factor for giving efforts defined as the amount of donation over income, implying that the higher income brackets are giving less money relative to their income level, than those with lower income level. Contrary to our expectation, self-esteem and welfare responsibility were not statistically significant explanatory variables.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.4
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• pp.1-13
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• 2018

The present study was conducted to analyze transport mode choice factors of shippers in Korea and to suggest policy implications and directions for future research. The findings showed that the research on freight mode choice factors in Korea is somewhat insufficient compared to that of other countries. In order to enhance the research, it is necessary to expand the number of studies and to strengthen the research to reflect characteristics of each transport mode. In particular, it is necessary to focus on identifying the characteristics of multimodal transport, including railway and shipping linked to truck. On the other hand, it was confirmed that the major factors influencing the choice of transport mode of shippers in Korea overlapped with foreign research cases. In addition, the implications for policy were derived when the analysis was separately conducted for Korea and other countries regarding individual transport mode and transport range. These results could be applied to various fields such as policy making to improve the efficiency of shippers' selection of transport mode and the estimation of transport mode choice model.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.3
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• pp.191-198
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• 2017

To study the behavior of structures subject to blast loads it is important to calculate the loads due to the explosives accurately, especially in the case of interior explosions. It is known that numerical method based on computational fluid dynamics can estimate relatively accurate blast load due to the interior explosion including reflection effect. However, the numerical method has disadvantages that it is difficult to model the analysis and it takes much time to analyze it. Therefore, in this study, the analytical method which can include the reflection effect of the interior explosion was studied. The target structures were set as the slabs of residential buildings subject to interior explosion that could lead to massive casualties and progressive collapses. First, the numerical method is used to investigate the interior explosion effect and the maximum deflection of the slab which was assumed to be elastic, and compared with the analytical method proposed in this study. In the proposed analytical method, we determine the weighting factor of the reflection effect using the beam theory so that the explosion load calculation method becomes more accurate.