• Communications for Statistical Applications and Methods
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• v.28 no.2
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• pp.171-188
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• 2021

Due to an increased demand for longevity risk analysis, various stochastic models have been suggested to evaluate uncertainly in estimated life expectancy and the associated value of future annuity payments. Recently updated data allow us to analyze mortality for a longer historical period and extended age ranges. This study followed up previous case studies using up-to-date empirical data on Korean mortality and the recently developed R package StMoMo for stochastic mortality models analysis. The suitability of stochastic mortality models, focusing on retirement ages, was investigated with goodness-of-fit, validity of models, and ability of generating reasonable sets of simulation paths of future mortality. Comparisons were made across various types of models. Based on the selected models, the variability of important estimated measures associated with pension, annuity, and reverse mortgage were quantified using simulations.

• Advances in materials Research
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• v.13 no.3
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• pp.203-210
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• 2024

Science mapping is a visual representation of the structure and dynamics of scholarly knowledge. Gas adsorption on catalyst supports is a crucial process in many catalytic reactions. The R package "Bibliometrix" and VosViewer software were employed for science mapping analysis. The results show that the upward trend but fluctuates from year to year for both annual scientific production and average article citations per year. Co-occurrence of the keywords were used to identify the primary fields of study and to map the existing state of research. Trending topics reveal some interesting features that support the growth of research in this field and are associated with emerging disciplines or areas of study that have not been extensively explored.

• Journal of the Microelectronics and Packaging Society
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• v.26 no.3
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• pp.81-88
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• 2019

In this study, the effects of graphene oxide (GO) addition on electromigration (EM) lifetime of Sn-3.0Ag-0.5Cu Pb-free solder joint between a ball grid array (BGA) package and printed circuit board (PCB) were investigated. After as-bonded, $(Cu,Ni)_6Sn_5$ intermetallic compound (IMC) was formed at the interface of package side finished with electroplated Ni/Au, while $Cu_6Sn_5$ IMC was formed at the interface of OSP-treated PCB side. Mean time to failure of solder joint without GO solder joint under $130^{\circ}C$ with a current density of $1.0{\times}10^3A/cm^2$ was 189.9 hrs and that with GO was 367.1 hrs. EM open failure was occurred at the interface of PCB side with smaller pad diameter than that of package side due to Cu consumption by electrons flow. Meanwhile, we observed that the added GO was distributed at the interface between $Cu_6Sn_5$ IMC and solder. Therefore, we assumed that EM reliability of solder joint with GO was superior to that of without GO by suppressing the Cu diffusion at current crowding regions.

• The Journal of Korean Academy of Sensory Integration
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• v.10 no.2
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• pp.33-39
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• 2012

Objective : The purpose of this study was identify the correlation of sensory processing type, academic ability and self-esteem in the college students. Methods : Duration of research was Act. 3rd, 2010 ~ Apr. 1st, 2011 and participants were 84 college students in Kyeong Nam. Method for study was the questionnaires investigation that included in AASP, self-esteem scale and grade. Data were statistically analyzed using the Statistical Package for the Social Sciences (SPSS) version 15 (SPSS Inc., Chicago, IL, USA). The correlation of various elements and core principles were analyzed using Pearson correlation. Results : Sensory avoiding (r=-.25), sensory sensitivity (r=-.22), sensory low registration (r=-.31) of sensory processing were correlation with self-esteem. sensory seeking (r=.22) of sensory processing correlation was correlation with academic ability. Conclusion : The results of this study emphasized that sensory processing ability is correlation with self-esteem and academic ability in the child as well as adult.

• Journal of Animal Science and Technology
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• v.51 no.4
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• pp.289-294
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• 2009

Inositol 1,4,5-triphosphate receptor type 1 (IP3R1) is a $Ca^{2+}$ release channel that responds to the second messenger IP3 and that modulates diverse cellular functions such as contraction/excitation, secretion, gene expression and cellular growth. We discovered single nucleotide polymorphisms (SNPs) within IP3R1 gene and analyzed associations between gene polymorphisms and carcass traits in Korean cattle (Hanwoo) in order to develop novel DNA markers at genomic level. Three SNPs were detected at the position of g.1428617A>G, g.1418843C>T and g.1414377C>T with 24 unrelated Hanwoo samples by direct sequencing of the PCR products. We found that genotype of g.1414377C>T SNP was associated with live weight (P<0.05) and carcass weight (P<0.01) using the general linear model of SAS package. These results suggest that polymorphism of IP3R1 gene was associated with weight-related traits in Hanwoo.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.2
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• pp.33-42
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• 2023

Throughout all industries, eco-friendliness is being promoted worldwide with focus on suppressing the environmental impact. With recent international environment policies and regulations supported by government, the electric vehicles demand is expected to increase rapidly. Battery system itself perform an essential role in EVs technology that is arranged in cells, modules, and packs, and each of them are connected mechanically and electrically. A multifaceted approach is necessary for battery pack bonding technologies. In this paper, pros and cons of applicable bonding technologies, such as resistance welding, laser and ultrasonic bonding used in constructing electric vehicle battery packs were compared. Each bonding technique has different advantages and limitations. Therefore, several criteria must be considered when determining which bonding technology is suitable for a battery cell. In particular, the shape and production scale of battery cells are seen as important factors in selecting a bonding method. While dealing with the types and components of battery cells, package bonding technologies and general issues, we will review suitable bonding technologies and suggest future directions.

• Women's Health Nursing
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• v.7 no.2
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• pp.157-168
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• 2001

The purpose of this study was to investigate of the relationship of the urinary incontinence, menopausal symptom and life satisfaction in middle aged women. The subjects of this study were 235 middle aged women, living in M city, during the period from June 21 to August 31, 2000. The instruments for this study were the urinary incontinence modified and adding by Lee Young Sook(1994), the menopausal symptom developed by Song Ae Ri and Chung Eun Soon(1998) and the life satisfaction translated and modified by Suh Kyung Hee(1988). Collected data were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients and stepwise multiple regression with SAS package. The result of this are as follows : 1. The total mean score of urinary incontinence was $1.56{\pm}0.58$ with a range of 0 to 4. The mean score on the menopausal symptom was $2.05{\pm}0.43$ with a range of 1 to 4. The mean life satisfaction score was $1.14{\pm}0.41$ with a range of 0 to 2. 2.General characteristics ralated to urinary incontinence were age and numbers of children (F=7.66, p=0.000, F=2.86, p=0.037). General characteristics ralated to menopausal symptom were age (F=7.37, p=0.000), occupation (t=5.33, p=0.021), problem of children (t=6.46, p=0.011) and marital satisfaction (F=5.65, p=0.004). General characteristics ralated to life satisfaction were type of housing (t=12.06, p=0.000), problem of children (t=6.96, p=0.008) and marital satisfaction (F=18.86, p=0.000). 3.The urinary incontinence and menopausal symptom were correlated positively (r=.235, p=.000). The urinary incontinence and life satisfaction were correlated negatively (r=-.114, p=.007). The menopausal symptom and life satisfaction were correlated negatively (r=-.277, p=.000). 4.The menopausal symptom, type of housing and marital satisfaction explained 16.6% of the variance for life satisfaction in the middle aged women.

• The Journal of Korean Society for School & Community Health Education
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• v.16 no.3
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• pp.1-15
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• 2015

Objectives: The purpose of this study was to examine the state of ADHD disposition among college students and the impact of their self-esteem on ADHD in an effort to provide useful information on the prevention of ADHD in adults. Methods: A survey was conducted from April 4 to June 30, 2015, on 264 selected students at two different universities that were respectively located in the Daegu and Gyeongsan city. As for data analysis, a statistical package SPSS WIN 18.0 was employed. Results: The findings of the study were as follows: There were significant differences in overall ADHD disposition according to academic year, religion and academic standing, and self-esteem varied with gender, presence or absence of a friend of the opposite gender, academic year and academic standing. There were differences in inattention-memory problems scores, one of the sub factors of adult ADHD, according to presence or absence of a friend of the opposite gender, academic year and academic standing. Self-esteem had a negative correlation with inattention-memory (r=-0.463), hyperactivity(r=-0.269) and impulsiveness(r=-0.233). When a regression analysis was made to determine influential factors for inattention-memory, religion(${\beta}=0.121$), academic standing(${\beta}=-0.153$) and self-esteem(${\beta}=-0.422$) were influential. Conclusions: Adult ADHD disposition and self-esteem of college students seems to be relationship. There was a positive correlation among inattention-memory, hyperactivity and impulsiveness that were three subfactors of adult ADHD.

• Journal of Korean Public Health Nursing
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• v.9 no.1
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• pp.44-58
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• 1995

This study was to investigated the relationship between health locus of control and health promoting behavior of College students. For this study, questionnaires were given to 300 students in the H University of Seoul and collected during the period from Nomber 17 to November 24, 1994. Health locus of control and health promoting behavior were measured by using the MHLC scale and a modified HPLP scale. Healthiness of life style is parameterized by self actualization, health responsibility, exercise, nutrition, stress management, and internal support. The data were analyzed using the statistics package SAS, yielding frequency, percentage, mean, standard deviation, t-test, ANOVA, Pearson's Correlation. The result of this analysis are as follows: 1. Among the components of health locus of control, internal health locus of control showed the highestscore (mean: 3. 12, standard deviation: 0.46). Powerful others health locus of control followed next with the mean of 2. 30 and the standard deviation of 0.44. Chance health locus of control showed the mean of 2.29, and the standard deviation of 0.43 2. The HPLP mean score and the standard deviation of practice of health promoting behavior were 2.51 and 0.31 respectively. 3. HPLP correlated positively with internal health locus of control (r= 0.20, p<.01) and powerful others locus of control (r= 0.21. p<.001). However, HPLP inversely correlated with chance locus of control (r=-0.13, p<.05) 4. The demographic variables representing sex (t= 2.26, p<.05), health status (F = 5.52, p<.01) showed connections to health promoting behavior. Therefore, nurses should consider health locus of control when they take care of College students to improve such health promoting behavior as self actualization, exercise, internal support, stress management, and health responsibility. Further research is required to discover factors influencing health promoting behavior of College students.

• International Journal of Reliability and Applications
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• v.7 no.1
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• pp.27-39
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• 2006

Many real world cases in material failure analysis do not follow perfectly the normal distribution. Forcing of the normality assumption may lead to inaccurate predictions and poor product quality. We examine the failure process of the internal bond (IB or tensile strength) of medium density fiberboard (MDF). We propose a forced censoring technique that closer fits the lower tails of strength distributions and better estimates extremely smaller percentiles, which may be valuable to continuous quality improvement initiatives. Further analyses are performed to build an accelerated common-shaped Weibull model for different product types using the $JMP^{(R)}$ Survival and Reliability platform. In this paper, a forced censoring technique is implemented for the first time as a software module, using $JMP^{(R)}$ Scripting Language (JSL) to expedite data processing, which is crucial for real-time manufacturing settings. Also, we use JSL to automate the task of fitting an accelerated Weibull model and testing model homogeneity in the shape parameter. Finally, a package script is written to readily provide field engineers customized reporting for model visualization, parameter estimation, and percentile forecasting. Our approach may be more accurate for product conformance evaluation, plus help reduce the cost of destructive testing and data management due to reduced frequency of testing. It may also be valuable for preventing field failure and improved product safety even when destructive testing is not reduced by yielding higher precision intervals at the same confidence level.