• Journal of the Korean Operations Research and Management Science Society
• /
• v.28 no.1
• /
• pp.11-23
• /
• 2003

This study Investigates the short and long-run dynamic relationships between the domestic and U.S. stock markets for the period of declining stock prices. It Is well known that the domestic stock market variations are largely caused by the U.S. stock market movements. Multivariate causal tty test Is utilized to examine the lead-lag relationships among four stock prices of KOSPI and KOSDAQ In the domestic part and DOWJONES and NASDAQ In the U.S. part. When the stock prices tend to decrease In the long run, It Is found that both KOSPI and KOSDAQ have closer relations with NASDAQ than DOWJONES. When both of domestic stock markets are severely fluctuate, bidirectional causal relationships appear to exist between NASDAQ and each of KOSPI and KOSDAQ. On the other hand. when the domestic stock markets are relatively stable, unidirectional causality Is found to exist between NASDAQ and each of KOSPI and KOSDAQ. which is explicitly validated by the analysis of variance decomposition.

• Journal of Ocean Engineering and Technology
• /
• v.24 no.1
• /
• pp.161-165
• /
• 2010

In the present study, process optimization for thermal-sprayed STS316 coating has been performed using $L_9(3^4)$ orthogonal array and analysis of variance (ANOVA). STS316 coatings were fabricated by flame spray process on steel substrate, and the hardness test and microstructure observation of the coatings were studied. The results of hardness test were analyzed by ANOVA. The ANOVA results showed that the spray distance had the greatest effect on hardness of the coating, on the other hands, the effects of oxygen gas flow and spray distance were ignorable. From these results, the optimal combination of the flame spray parameters could be derived, and confirmation experiment was carried out to verify these derived results. The calculated hardness of the coatings by ANOVA was found to approximately close to that of confirmation experimental result. Thus, it was considered that design of experiments using orthogonal array and ANOVA was effective for process optimization of thermal-sprayed STS316 coating.

• Journal of Power System Engineering
• /
• v.13 no.5
• /
• pp.89-94
• /
• 2009

In this work, the optimal process has been designed by $L_9(3^4)$ orthogonal array and analysis of variance(ANOVA) for thermal-sprayed Ni-based hard coating. Ni-based hard coatings were fabricated by flame spray process on steel substrate. Then, the hardness test and observation of microstructure of the coatings were performed. The results of hardness test were analyzed by ANOVA. The ANOVA results demonstrated that the acetylene gas flow had the greatest effect on hardness of the coatings. The oxygen gas flow was found to have a neglecting effect. From these results, the optimal combination of the flame spray parameters could be predicted. The calculated hardness of the coatings by ANOVA was found to lie close to that of confirmation experimental result. Thus, it was considered that design of experiments design using orthogonal array and ANOVA was useful to determine optimal process of thermal-sprayed Ni-based hard coating.

• Korean Journal of Health Education and Promotion
• /
• v.21 no.3
• /
• pp.117-131
• /
• 2004

Purpose: This study was conducted to evaluate the health behaviors and to find out risk factors of blood pressure of adult women in a rural area. Method: The convenient sample consisted of 159 adult women who lived in G-gun. The data was collected using a self-report questionnaire for health behaviors and mercury type sphygmomanometer for BP, between Jun I and August 15, 2003. Health behaviors measured smoking, alcohol, salt, lipid, stress, exercise, coffee, BMI and medication. To accomplish the goal of study, descriptive statistics, t-test, $x^2$-test, ANOVA and multiple regression analysis were. performed with SPSS 10.0. Results: The average age of subjects was 49.2(SD7.34)years old. The average SBP and DBP of subjects were 126.22mmHg(SDl6.73) and 8 1.25mmHg(SDl 0.31). There were significant differences in smoking(p=.000), cigarette consumption(p=.001), smoking duration(p=.000), BMI(p=.033), medication (p=.001), family history(p=.000) between normotensive and hypertensive. The main risk factors on SBP were medication, age, BMI, family history and smoking duration by 35.7% of the total variance these variables explained SBP. The main risk factors on DBP were BMI, education and medication by 17.60% of the total variance these variables explained DBP. Conclusion: These results suggest that health professional have to emphasize prevention of obesity, lasting medication and no smoking for prevention and management of hypertension in community health promotion program.

• The Journal of Korean Medicine
• /
• v.25 no.1
• /
• pp.172-187
• /
• 2004

Objectives : To characterize four types of obesity and to effectively improve the treatment of obesity through Oriental medicine Methods : At 00 Oriental Medical Center, 203 female subjects who intented to lose weight were requested to complete a questionnaire. These participants were also given physical tests. The Questionnaire consisted of questions both about general life style and obesity in oriental medicine framework. The physical tests were blood tests, a body composition via Inbody 2.0, and physical strength tests. One-way analysis of variance was done to compare the means of items and physical tests between four types of obesity. Duncan was used by post hoc test. Results : 1. Significant differences between obesity type III and obesity type IV in ever tried to lose weight, childhood obesity and excercise times were observed in the questionnaire of general life style(p<0.05). 2. Ducan test showed significant differences between four obesity types in diseases (p<0.05). 3. Significant differences between four obesity types in height, % body fat muscular endurance, soft lean mass, fat mass, Trigliceride, Total cholesterol and ${\gamma}-GTP$ were observed (p<0.05). Conclusions : Further clinical research is necessary in the four types of obesity explored. The diagnosis and treatment based on these types should be further studied.

• Child Health Nursing Research
• /
• v.26 no.2
• /
• pp.181-189
• /
• 2020

Purpose: This study explored the relationships of maturity fears and appearance interest(interest in appearance, interest in weight) with self-concept among girls with precocious puberty. Methods: The participants for this study were 120 elementary school students (8 to 10 years old) and their parents from two hospitals located in Chungcheong Province. Data were collected from January to February 2019 using self-reported questionnaires. The collected data were analyzed using descriptive statistics, the independent t-test, the Mann-Whitney U test, one-way analysis of variance, Pearson correlation coefficients, and multiple regression analysis in SPSS for Windows version 23.0. Results: Statistically significant negative correlations were found between self-concept and maturity fears (r=-.34, p<.001) and interest in weight (r=-.29, p=.001). Maturity fears were identified as a factor affecting the self-concept of girls with precocious puberty (β=-.34, p<.001). This variable explained 11.5% of the variance in the self-concept of girls who experienced precocious puberty. Conclusion: This study confirmed that maturity fears had a major influence on self-concept in girls with precocious puberty. The results of this study can be used as basic data for the development of a psychosocial nursing intervention program for girls who experience precocious puberty.

• Child Health Nursing Research
• /
• v.24 no.2
• /
• pp.199-207
• /
• 2018

Purpose: The purpose of this study was to investigate resilience, coping, and mental health in relation to burnout and to identify factors influencing burnout in student nurses. Methods: A descriptive correlational study was conducted. The participants were 241 student nurses from 2 universities in B city. Data were analyzed using the t-test, analysis of variance, the Pearson correlation coefficient, the $Scheff{\acute{e}}$ test, and multiple regression analysis. Results: The mean score for burnout in student nurses was 3.01 out of 5 points. Burnout explained 29.2% of the variance in satisfaction with college life (${\beta}=-.367$, p<.001), coping (${\beta}=.293$, p<.001), mental health (${\beta}=.228$, p=.011), and training hospital (${\beta}=-.198$, p=.026). Conclusion: The results of our research suggest that satisfaction with college life is an important variable affecting burnout student nurses. Therefore, education is needed in order to develop for more effective teaching coping methods and strategies and to reduce burnout with nursing practice.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.24 no.2
• /
• pp.43-51
• /
• 2020

After the accelerated aging, the bulkhead initiator using high explosives was carried out to verify aging characteristics. The Thru-Bulkhead Initiator operates by transmitting shock-wave generated from micro-initiator to the acceptor and the ignition explosives through the bulkhead. In order to evaluate the life-time of the product, the accelerated aging condition was set according to the life-time, and the ignition performance of the sample was measured every 10 cycles by measuring the delay time and the maximum pressure through the 10cc closed bomb test. In addition, variance analysis was used to determine aging.

• International Journal of Highway Engineering
• /
• v.18 no.3
• /
• pp.109-114
• /
• 2016

PURPOSES : The demand for extending national highways is increasing, but traffic monitoring is hindered because of resource limitations. Hence, this study classified highway segments into 5 types to improve the efficiency of short-term traffic count planning. METHODS : The traffic volume trends of 880 highway segments were classified through R-squared and linear regression analyses; the steadiness of traffic volume trends was evaluated through coefficient of variance (COV), and the normality of the data were determined through the Shapiro-Wilk W-test. RESULTS : Of the 880 segments, 574 segments had relatively low COV and were classified as type 1 segments, and 123 and 64 segments with increasing and decreasing traffic volume trends were classified as type 2 and type 3 segments, respectively; 80 segments that failed the normality test were classified as type 4, and the remaining 39 were classified as type 5 segments. CONCLUSIONS : A theoretical basis for biennial count planning was established. Biennial count is recommended for types 1~4 because their mean absolute percentage errors (MAPEs) are approximately 10%. For type 5 (MAPE =19.26%), the conventional annual count can be continued. The results of this analysis can reduce the traffic monitoring budget.

• YAKHAK HOEJI
• /
• v.33 no.4
• /
• pp.229-236
• /
• 1989

Even though two different preparations are chemically equivalent, the variance of bioavailability differenciates the clinical effect of preparations, so that the preparations need to be evaluated by comparing bioavailability in vivo as well as chemical equivalence. In this study, bioequivalence tests of commercially available isoniazid tablets A, B, C and D (standard) were performed to give some guidelines to bioequivalence test. The bioavailability parameters obtained by drug administeration were statistically analyzed. Statistical evaluation of the data involved an analysis of variance for a cross over design. Cross over design was employed with 8 healthy volunteers. The results were within 20% difference of mean value in the AUC, Cmax, Tmax and amount of urinary excretion (Au) between standard and isoniazid tablets. The results of ANOVA showed no significant differences for 'group or sequence', but almost not for 'between subjects'. The tablet. A, B and D were within 20 min, but tablet C was within 50 min. Tablet A was biologically equivalent in the Au. tablet B biologically equivalent in the Au and AUC. Tablet C was biologically equivalent in the Au. The relationship between the dissolution rate and Au was significant.