• Journal of the Korea Society for Simulation
• /
• v.29 no.3
• /
• pp.57-72
• /
• 2020

To respond to the threat of Long range artillery of North Korea, it is necessary to establish the Korean counter long range artillery intercept system(CLRAIS). The purpose of this study is to study the operational concept of the CLRAIS against the threat of long range artillery of North Korea, and to develop the operational effectiveness process of the CLRAIS. First, we set up the operating concept of the CLRAIS and established the concept of an effectiveness in a many-to-many engagement situation and a process to derive it. Based on this, a tool was developed to analyze the actual effectiveness. In order to find out the factors influencing the effectiveness in many-to-many engagement situations, simulation experiments were performed by combining various variables such as detection assets, engagement control, and launchpad performance. As a result, it was found that in addition to the missile performance, the performance of the detection assets and the engagement control center had a significant impact on the intercept rate and the defense success rate. These findings can be used to understand important indicators in terms of effectiveness in many-to-many engagement situations in the future development of weapon system, and to determine the development direction and target value of each element necessary for the level of defense success rate to be achieved.

• Journal of the Korean Society for Railway
• /
• v.19 no.4
• /
• pp.539-546
• /
• 2016

It is over 12 years since the launch of Korea Train eXpress (KTX) services. Demand for the KTX has been on the increase continuously but few studies have been produced related to this phenomenon. KTX passenger demand has been constantly increasing due to influencing factors such as the expansion of network, rise of oil prices, etc. In this study, our main focus is to verify that there are other types of elements that are causing an increase in KTX demand; our approach looks at changes in social and psychological aspect that have occurred due to the reduction of travel time and cost, as well as the imposition of a five-day workweek. In other words, we considered diffusion theory in the marketing area, which affects product selection and purchasing attitudes, as a key factor that is causing passenger demand to increase. That is to say that it is hypothesized that the demand for travel on the KTX has increased due to the train's utility, which is spread by the diffusion effect Therefore, the Bass diffusion model was applied to explain the dramatic increase in KTX passenger demand. Based on this foundation, it was also discussed how certain marketing strategies that incorporate the diffusion effect should be considered variously for sustainable management of rail transportation, while considering a steady passenger demand.

• Journal of The Korean Association of Information Education
• /
• v.25 no.4
• /
• pp.591-601
• /
• 2021

This study focuses on the ICT literacy, the perceived value of ICT utilization, and the perceived use of ICT environment as the factors influencing the activation of ICT using classes, in order to identify how these differences affect intended use of ICT. A total of 3,942 high school teachers participated in the survey. Two factor analyses were conducted to verify and check the validities of measurement items for independent and dependent variables. With the research questions, a multiple regression analysis was implemented to verify the predictive power of the independent variables on the teachers' ICT utilization. All the independent variables set in the research issue had a significant influence on the intended use of ICT, which is a dependent variable. ICT utilization was found as the most influential variables followed by the perceived value of ICT utilization, the affective domain of ICT literacy, and the psychomotor domain of ICT literacy, the cognitive domain of ICT literacy, and the perceived use of ICT environment. In order to enhance teachers' ICT utilization in school settings, teachers should understand the educational value of ICT utilization and recognize its necessity and importance.

• Journal of Wetlands Research
• /
• v.23 no.4
• /
• pp.296-306
• /
• 2021

Elasticity is a statistical technique that interprets the changing pattern of another variable according to a change in one variable as a quantitative numerical value and provides more information than correlation analysis and is widely used in climate change research. In this study the elasticity was calculated and sensitivity analysis was performed using air temperature and water quality data of the major tributaries of the Nakdong River. In addition the confidence interval for the elasticity was calculated using the T-Test and the validity of the elasticity was examined. The strength of elasticity shows high strength in the order of summer>fall>spring>winter and the direction shows regional characteristics with both negative and positive elasticity. After performing hierarchical cluster analysis on monthly observation data they were classified into 5 clusters and the characteristics of each cluster were visually analyzed using a parallel coordinate graph. The direction and intensity of the air temperature elasticity show regional characteristics due to the relatively high population density and complex influencing factors such as sewage treatment plants, small-scale livestock houses and agricultural activities. In the case of TP it shows great regional variability according to the circulation of nutrients in the ecosystem caused by algae growth and death according to temperature changes. Since the air temperature elasticity of the major tributaries of the Nakdong River is over weak and is valid at the significance level of 5%, it was analyzed that there is a change in water quality according to the air temperature change.

• Journal of the Korean Society of Radiology
• /
• v.15 no.5
• /
• pp.683-690
• /
• 2021

The purpose of this study was to confirm the degree of academic achievement among university students in the Department of Radiology(science) who are in the continuation of the COVID-19 situation and to investigate the effect of smart media literacy and ego-resilience on academic achievement. The research method was descriptive research. Data was 188 students collected from June 1 to July 31 in 2021 using structured questionnaires as students in the Department of Radiology(science). Collected data was analyzed using descriptive statistics, t-test, ANOVA, Cronbach's pearson's correlation, multiple regression analysis with SPSS/WIN 21.0. The result of the study showed that the academic achievement was 3.43, ego-resilience was 3.37 and smart media literacy was 2.94. There was a significant positive correlation between a academic achievement and smart media literacy, academic achievement and ego-resilience. Factors influencing academic achievement were smart media literacy, ego-resilience, major satisfaction and practice satisfaction. As a result of the above research. it is necessary to develop and apply curriculums, extra curriculums and educational programs that improve the smart media literacy and ego-resilience in order to improve the academic achievement. In addition, it is necessary to improve major satisfaction and practice satisfaction.

• Journal of the Korean Society of Radiology
• /
• v.15 no.2
• /
• pp.93-100
• /
• 2021

The purpose of this study is to find out the factors that affect the patient's exposure dose during the abdominal CT scan using the bolus tracking technique, and reducing the radiation exposure to the patient during the abdominal CT scan using the bolus tracking technique by adjusting the delay time according to the corresponding factor. The experiment was divided into two parts, and the first experiment was conducted with 300 patients There were 188 males and 112 females, and their average age was 58±12.18(19~85). In the second experiment, 150 subjects (100 males and 50 females) who were undergoing their follow-up examination among the first experiment subjects, and the difference in dose before and after was compared by applying the delay time according to the influencing factor. As a result of the first experiment, there was a relationship between the arrival time of the contrast media and the heart rate, and it was found that the arrival time decreased as the heart rate increased for both men and women. As a result of the second experiment, the average dose of CTDIvol and DLP before/after applying the delay time according to the heart rate decreased 4.98 mGy and 5.33 mGy·cm in the male group, and 3.54 mGy and 3.88 mGy·cm in the female group. By applying proper delay time according to the patient's heart rate during abdominal CT scan with the bolus tracking technique, the radiation exposure dose of the patient can be reduced.

• Korean Journal of Ecology and Environment
• /
• v.54 no.4
• /
• pp.363-373
• /
• 2021

An ecological niche is defined as the specific role of a species influenced by time, space, and other resources. By investigating overlaps between ecological niches of different species, we could estimate the degrees of interspecific competition. Such studies often use geographic information systems (GIS) to discover niche overlaps between species. In this study, we used GIS to estimate the spatial niches of two Korean frog species(Pelophylax nigromaculatus and P. chosenicus). This enabled us to predict their geographic distributions in order to identify their coexistence regions and distribution patterns. The results confirmed that altitude was an important variable for predicting their distribution, with a correlation with their climatic range. Spatial distributions of the two frog species were highly overlapped, as the distribution range for P. nigromaculatus included most of the range of P. chosenicus, showing a sympatric distribution pattern. Within the coexisting regions, however, the presence sites for the two species did not overlap, implying weak competition. To confirm the principal factors influencing their competitive relationship and reasons for their sympatric distribution pattern, we need more detailed in-depth studies on the diverse environmental variables within the regions where the two species coexist. By doing so, we would be able to identify various mechanisms for avoiding competition in sympatric frog species.

• 한국노년학
• /
• v.38 no.2
• /
• pp.291-308
• /
• 2018

The purpose of this study is to analyze the factors influencing financial preparedness for retirement of the middle-aged North Korean defectors (resettling in South Korea) using concepts of 'financial literacy' and 'financial inclusion'. Those questioned were 100 North Korean defectors of 40-60 years-old residing in Seoul and Gyeonggi-do Province selected by convenience sampling, one of the non-probability sampling. Path analysis is used as a main analysis method. The results of the study show a direct effect in which increased financial literacy resulted in better financial preparedness for retirement among middle-aged North Korean defectors at a statistically significant level. In addition, by boost-trapping method, financial inclusion has its mediating effect on the relationship between financial literacy and financial preparedness for retirement. However, this study shows that influence of financial literacy on financial preparedness for retirement is different across economic statues. The mediating effect of financial inclusion on the relationship between financial literacy and financial preparedness is statistically significant only for the low-income group. Meanwhile, for the above average income group, financial literacy has a direct effect on the financial preparedness after retirement at a statistically significant level. Based on these results, this study suggests practical and policy implementation such as necessity of customized financial education suited to their economic status, development of financial instruments for retirement, introduction of financial social workers to prepare stable old age of North Korean defectors.

• International Area Studies Review
• /
• v.22 no.4
• /
• pp.99-121
• /
• 2018

This study investigated the factors influencing the knowledge acquisition of Thai local partners from advanced foreign partners through international joint ventures(IJVs). For this purpose, this study initially identified three dimensions of characteristics in the context of IJVs that would influence local partners' knowledge acquisition - a local partners' own characteristic (absorptive capacity), a relationship characteristic with IJVs (proximity to the equal equity ownership), and a relationship characteristic with foreign partners (trust), and examined their effects on local partners' knowledge acquisition. The study further investigated the moderating effects of the tacitness of knowledge on the relationships between those characteristics and knowledge acquisition. Based on the data collected from Thai IJV local partners, results revealed that a local partners' own characteristic, absorptive capacity, and a relationship characteristic with IJVs, proximity to the equal equity ownership, had a strong positive effect on local partners' knowledge acquisition. Results further showed that the tacitness of knowledge strengthened the relationships between absorptive capacity and knowledge acquisition and between trust and knowledge acquisition, but not the relationship between proximity to the equal equity ownership and knowledge acquisition.

• Journal of vocational education research
• /
• v.29 no.3
• /
• pp.23-40
• /
• 2010

Career guidance refers to services intended to assist students to make educational and occupational choices and to manage their careers. Young students, specially enrolled in vocational high schools, need programs to help them make transitions to the working world and to re-engage with further learning, and career guidance needs to be part of such programs. Teachers assume the critical roles in planning and organizing the career guidance programs in vocational high schools. The program includes career information provision, assessment and self-assessment tools, career counseling, work search, etc. In this study, we developed a research model based upon TRA(theory of reasoned action) developed by Ajzen and Fishbein to investigate the factors influencing the intention to provide career guidance services to students in vocational high schools. Based on 155 survey responses from vocational high school teachers, we show that attitude and subjective norm motivate teachers to provide career guidance services, and that attitude toward career guidance is directly influenced by self-efficacy for career guidance and burden from extra work. It was also confirmed that facilitating condition is the antecedent of self-efficacy. But contrary to our expectation, self-efficacy for career guidance has no significant effect on the intention for providing career guidance services at 5% significance level. In light of these findings, implications for theory and practice are discussed.