• Restorative Dentistry and Endodontics
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• v.28 no.4
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• pp.334-340
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• 2003

This study was performed to evaluate the actual temperature rise on the surface of Buchanan plugger using thermocouple. The heat carrier system 'System B Heatsource'(Model 1005, Analytic Technologies, Redmond, WA, USA) and the Buchanan pluggers of F, FM, M and ML sizes are used for this study. The temperature was set to 200^{\circ}C on digital display and the power level on it was set to 10. Five thermocouples were placed in direct contact with the surface of each size of Buchanan's pluggers at 1 mm increments from the tip to the 4 mm length of shank. The heat control spring was touched for 5 seconds. and the temperature rise on the surface of the pluggers were measured at 1 sec intervals for more than 5 seconds with an accuracy of 0.01 using Data Logger. The data were statistically analyzed by one-way ANOVA. The results were as follows. 1. The position at which the temperature peaked was approximately at 1~2 mm far from the tip of Buchanan plugger (p<0.01). 2. The peak temperature was $215.25{\pm}2.28^{\circ}C$ in F plugger. $185.94{\pm}2.19^{\circ}C$ in FM plugger, $169.51{\pm}9.12^{\circ}C$ in M plugger, and 160.79{\pm}1.27^{\circ}C in ML plugger and the peak temperature was highest in F plugger and followed by. in descending order. FM plugger. M plugger. ML plugger showed the lowest peak temperature (p<0.01). 3. The temperature on the plugger was decreased with the increase of touching time. This results suggest that the actual temperature on the surface of the pluggers does not correlate well with the temperature set on digital display. Heat concentrates around the tip. The larger plugger reveals lower temperature rise relatively.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.47-58
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• 2012

This study selects political and military decision factors of Participatory Government's Wartime Operational Control(OPCON) Transition and analyzes, both quantitatively and qualitatively, the effects and relations between those factors. Previous research utilizing the Analytic Hierarchy Process(AHP) selected their decision factors based on academic data and field experience, requiring more objective analysis of the factors. For this study, we conducted a survey among security subject matter experts(SME) both online and offline. The results show that OPCON transition's decision factors were to 'recover military sovereignty', 'set the conditions for peaceful reunification' and 'improve ROK image through enhancing national power' which differs little from the previous AHP method studies. It also showed that 'recover military sovereignty' and 'set the conditions for peaceful reunification' had no relationship to each other and that the key factor that decided the OPCON Transition was actually 'recover military sovereignty' which represents the interest of the liberal party in ROK. This study finds its meaning by analyzing the decision factors of Participartory Government's OPCON Transition thorugh Delphi and DEMATEL method.

• The Mathematical Education
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• v.27 no.1
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• pp.15-23
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• 1988

We are at the onset of a major revolution in education, a revolution unparalleled since the invention of the printing press. The computer will be the instrument of this revolution. Computers and computer application are everywhere these days. Everyone can't avoid the influence of the computer in today's world. The computer is no longer a magical, unfamiliar tool that is used only by researchers or scholars or scientists. The computer helps us do our jobs and even routine tasks more effectively and efficiently. More importantly, it gives us power never before available to solve complex problems. Mathematics instruction in secondary schools is frequently perceived to be more a amendable to the use of computers than are other areas of the school curriculum. This is based on the perception of mathematics as a subject with clearly defined objectives and outcomes that can be reliably measured by devices readily at hand or easily constructed by teachers or researchers. Because of this reason, the first large-scale computerized curriculum projects were in mathematics, and the first educational computer games were mathematics games. And now, the entire mathematics curriculum appears to be the first of the traditional school curriculum areas to be undergoing substantial trasformation because of computers. Recently, many research-Institutes of our country are going to study on computers in orders to use it in mathematics education, but the study is still start ing-step. In order to keep abreast of this trend necessity, and to enhance mathematics teaching/learning which is instructed lecture-based teaching/learning at the present time, this study aims to develop/present practical method of computer-using. This is devided into three methods. 1. Programming teaching/learning method This part is presented the following five types which can teach/learn the mathematical concepts and principle through concise program. (Type 1) Complete a program. (Type 2) Know the given program's content and predict the output. (Type 3) Write a program of the given flow-chart and solve the problem. (Type 4) Make an inference from an error message, find errors and correct them. (Type 5) Investigate complex mathematical fact through program and annotate a program. 2. Problem-solving teaching/learning method solving This part is illustrated how a computer can be used as a tool to help students solve realistic mathematical problems while simultaneously reinforcing their understanding of problem-solving processes. Here, four different problems are presented. For each problem, a four-stage problem-solving model of polya is given: Problem statement, Problem analysis, Computer program, and Looking back/Looking ahead. 3. CAI program teaching/learning method This part is developed/presented courseware of sine theorem section (Mathematics I for high school) in order to avail individualized learning or interactive learning with teacher. (Appendix I, II)

• Journal of Pharmaceutical Investigation
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• v.29 no.4
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• pp.295-307
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• 1999

Using a Rheometries Fluids Spectrometer (RFS II), the dynamic viscoelastic properties of aqueous poly(ethylene oxide) (PEO) solutions in small amplitude oscillatory shear flow fields have been measured over a wide range of angular frequencies. The angular frequency dependence of the storage and loss moduli at various molecular weights and concentrations was reported in detail, and the result was interpreted using the concept of a Deborah number De. In addition, the experimentally determined critical angular frequency at which the storage and loss moduli become equivalent was compared with the calculated characteristic time (or its inverse value), and their physical significance in analyzing the dynamic viscoelastic behavior was discussed. Finally, the relationship between steady shear flow and dynamic viscoelstic properties was examined by evaluating the applicability of some proposed models that describe the correlations between steady flow viscosity and dynamic viscosity, dynamic fluidity, and complex viscosity. Main results obtained from this study can be summarized as follows: (1) At lower angular frequencies where De<1, the loss modulus is larger than the storage modulus. However, such a relation between the two moduli is reversed at higher angular frequencies where De>l, indicating that the elastic behavior becomes dominant to the viscous behavior at frequency range higher than a critical angular frequency. (2) A critical angular frequency is decreased as an increase in concentration and/or molecular weight. Both the viscous and elastic properties show a stronger dependence on the molecular weight than on the concentration. (3) A characteristic time is increased with increasing concentration and/or molecular weight. The power-law relationship holds between the inverse value of a characteristic time and a critical angular frequency. (4) Among the previously proposed models, the Cox-Merz rule implying the equivalence between the steady flow viscosity and the magnitude of the complex viscosity has the best validity. The Osaki relation can be regarded to some extent as a suitable model. However, the DeWitt, Pao and HusebyBlyler models are not applicable to describe the correlations between steady shear flow and dynamic viscoelastic properties.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.213-222
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• 2016

The purpose of this study was to investigate the knowledge and attitude toward the elderly, aging anxiety, and attitude toward caring the elderly and to identify influencing factors of attitude toward caring the elderly in nursing students. Participants were 227 nursing students from three college of nursing in D-city and K region. Data was collected by structured questionnaire on subjects' characteristics, knowledge toward the elderly, attitude toward the elderly, aging anxiety, and attitude toward caring the elderly. Data were analyzed using descriptive statistics, t-test, one way ANOVA, Pearson correlation coefficient, and stepwise multiple regression analysis with SPSS/WIN 19.0 program. The average score of knowledge, aging anxiety, attitude toward the elderly, and attitude toward caring the elderly of participants were 14.78, 2.88, 4.09, 5.16. Factors significantly affecting attitude toward caring the elderly were attitude toward the elderly, preference of caring for the elderly, aging anxiety, favorable type to be support as a parent. Explanatory power of the model was 24.7%. The results of this study suggest that interventions may be necessary to improve attitude toward caring the elderly among nursing students. It is essential to develop the strategy of providing positive experience with the elderly for nursing students as well as geriatric nursing education.

• Journal of the Korean Applied Science and Technology
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• v.37 no.3
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• pp.613-624
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• 2020

This study is a descriptive research to grasp the effects of nursing performance on emotional labor, job stress and resilience in general hospital nurses. Method: I surveyed them using a structured questionnaire for collecting data from Aug. 20, 2019 to Sep. 2, 2019. The collected data were analyzed by the frequency, the percentage, t-test, ANOVA, Scheffe's Test, Pearson's Correlation Coefficient, and Multiple Regression Analysis. Results: The factors affecting nursing performance of the subjects were resilience (β=0.58, p<.001), and current position is head nurse (β=0.21, p<.01), the number of working years at current working place (β=0.18, p<.05). The F statistics for the fit of the estimated regression model was very significant as 30.901(p<.001) and the explanatory power was 42.4%. Conclusion: The results of this study showed that resilience was the most influential factor to nursing performance of general hospital nurses, and the number of working years at current working place was the most influential factor to the performance of head nurses. Therefore, it is necessary to develop practical programs strengthening resilience of nurses for the improvement of nursing performance and to apply strategies on development.

• Journal of Distribution Science
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• v.13 no.12
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• pp.113-131
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• 2015

Purpose - In today's era of globalization, the competitive power of enterprises is growing fiercer, calling for organizations to be able to respond flexibly to survive and maintain predominance in competition. In turn, keen competition exists among enterprises for the systematic management of members' knowledge to secure predominance in such competition. Under such circumstances, SMEs must find and utilize positive causes for change that affect organizational performance. The objective of this study is to analyze the structural relationship between four factors known from prior research-a CEO's positive leadership, members' positive life positions, learning organization activities, and job engagement-and organizational performance. Research design, data, and methodology - To achieve this objective, this study established the following four research problems. First, do CEOs' positive leadership, members' positive life positions, learning organization activities, and job engagement affect organizational performance? Second, do CEOs' positive leadership, members' positive life positions, and learning organization activities affect job engagement? Third, do CEOs' positive leadership and members' positive life positions affect learning organization activities? Fourth, does CEOs' positive leadership affect members' positive life positions. Additionally, to achieve the objective of this study, the research model was selected on the basis of a documentary survey of 787 full-time employees at 100 SMEs, which was used to collect related data. Results - The following conclusions were drawn. First, a CEO's positive leadership directly affects members' positive life positions, learning organization activities, and job engagement. Second, positive leadership only indirectly affects organizational performance. That is, positive leadership has an indirect effect on organizational performance given the parameters of members' positive life positions, learning organization activities, and job engagement. Third, members' positive life positions directly affect learning organization activities and job engagement, but indirectly affect organizational performance with learning organization activities and job engagement as parameters. Fourth, learning organization activities directly affect job engagement and organizational performance. Additionally, learning organization activities indirectly affect organizational performance with job engagement as a parameter. Fifth, job engagement directly affects organizational performance. Conclusions - A CEO's positive leadership and members' positive life positions do not directly affect organizational performance but have a positive effect through learning organization activities and job engagement. In particular, CEOs' positive leadership was proven to be the major factor to affect members' positive life positions, learning organization attitudes, and job engagement, and learning organization activities and job engagement were found to be major factors that directly affect organizational performance. Considering these conclusions, the direct effect of a CEO's positive leadership on organizational performance is not statistically significant but seems to affect members' positive life positions, learning organization activities, and job engagement, which ultimately affects organizational performance. In addition, CEOs' positive leadership is an important factor that enhances the factors with the strongest effect on organizational performance-activities of learning organizations and job engagement.

• The Journal of the Korea Contents Association
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• v.15 no.2
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• pp.333-343
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• 2015

The purpose of this study is to investigate the factors that affect the fall prevention awareness of care-givers working at long-term care hospitals. A convenience sampling method was used to select care-givers who worked at 7 different long term care hospitals which were located in D city and N city. Data were collected from July 2014 to August 2014. 200 data were used for analysis out of 215 data which were collected. The hierarchical regression analysis reveals the following results: Firstly, the effects of care-givers' education level, certificate status, period of work experience and fall-related learning hours on their fall prevention awareness level were statistically significant. Secondly, among fall prevention health beliefs, perceived benefit, perceived disability, perceived sensitivity and self-efficacy were positively related to the level of fall prevention awareness. Thirdly, while such factors as perceived benefit, perceived sensitivity and self-efficacy showed positive effects on the fall prevention awareness, the period of work experience had negative effects. The regression model shows the power of explanation of 31.7 percents. In conclusion, the study suggests a fine-tuned program to improve care-givers' fall prevention awareness in a way of promoting fall prevention self-efficacy, perceived benefits and perceived sensitivity while considering the care-givers' period of work experience.

• Journal of Digital Convergence
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• v.18 no.3
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• pp.259-266
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• 2020

This paper attempted to find the convergence factors related to the organizational citizenship behavior of hospital administration staff(HAS). The survey was conducted on 274 administrative staff at 22 hospitals in J regions randomly selected using self-administered questionnaires. The survey period took about a month from July 1 to July 31, 2019. The hierarchical multiple regression analysis shows the following results. The organizational citizenship behavior of respondents turned out to be significantly higher in following groups: The higher the procedure justice, sub-areas of organization justice, the higher the intragroup trust, and the higher the organizational commitment. Their explanatory power was 41.9%. The results of the study indicate that the efforts, to increase organization justice, intragroup trust and organizational commitment, are required to improve organizational citizenship behavior among HAS. The above results are expected to be utilized in human resource management and industrial health education of medical institutions that enhance organizational citizenship behavior of HAS. Later research requires the establishment of a structural equation model that affects organizational citizenship behavior of HAS.

• The Korean Journal of Financial Management
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• v.25 no.3
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• pp.1-32
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• 2008

This study examines the changes and determinants of cash to assets ratios(cash ratios) by analyzing 14,016 Korean manufacturing firms sample for the period of $1999{\sim}2004$. The major findings can be summarized as follows. First, the average cash ratios for Korean manufacturing firms have increased from 4.7 percent of 1999 to 5.2 percent of 2004. In addition, the average cash holdings per firm also have increased from 4.3 billion Won to 8.0 billion Won during the same period. However, the capital expenditures relative to cash ratios or operating cash flow have decreased significantly, confirming the notion that physical investment of Korean manufacturing sector has been shrinking recently. Second, in regression tests with panel data, the coefficients of target adjustment variables show the expected negative signs, but coefficients of the deficit of fund variables show the unexpected positive signs. Thus, the evidence seems to be supportive of static tradeoff model of cash holdings. Third, in regression tests to find the determinants of cash ratios, most of the variables show similar results as the previous studies. However, in terms of adjusted coefficient of determination and F-statistic, the firm-characteristic variables suggested by static trade-off theory have more explanatory power than the variables suggested by pecking order theory.