• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.20 no.2
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• pp.79-82
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• 1984

Seasonal and secular variations of water temperature in Chungmu port were investigated with the data obtained from the Technical Reports(1976~1983) of Hydrographic Office. Monthly and annual range of water temperature were 2 to 8$^{\circ}C$ and 18 to 21$^{\circ}C$, respectively. The coefficients of variance of monthly mean water temperature were 0.015(February, 1976) to 0.208(December, 1980) and their values were smaller in the summer season than in the winter season. The result of harmonic analysis for investigating the seasonal variation of water temperature was T(t)=15.66+8.06 cos(10$^{\circ}$t-233.5)+0.92 cos(20$^{\circ}$t-216). The periods of secular variation were about 2 years and 3 years.

• Korean Journal of Adult Nursing
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• v.24 no.6
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• pp.597-606
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• 2012

Purpose: This study was to describe the uncertainty, depression, physical symptom, and family support among patients undergoing dialysis. Further, the factors that impact uncertainty were also examined. Methods: A convenience sample of 145 patients who received dialysis was selected. A descriptive correlation study was conducted. Data were collected using structured questionnaires and the collected data were analyzed using descriptive statistics and multiple regression analysis. Results: The patient who received more than five years of dialysis reported higher levels on inconsistency of uncertainty than patient with less than five years. These latter patients' reported uncertainty was positively correlated with depression, whereas, patients family support was correlated with uncertainty. The group's uncertainty with less than five years of dialysis explained about 13% of the variance. In contrast, variables of education level, family support, and monthly income were predictors of uncertainty and explained 33% of the variation. Conclusion: These results can provide for nursing intervention to facilitate reduction of uncertainty. To provide dialysis period-sensitive nursing intervention for uncertainty among dialysis patient, depression should be considered below five years. While factors such as education level, family support, and monthly income should be taken into account over five years.

• Restorative Dentistry and Endodontics
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• v.45 no.1
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• pp.10.1-10.8
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• 2020

Objectives: This study aimed to compare the shear bond strength (SBS) of a self-adhering flowable composite (Dyad Flow) and a bulk-fill flowable composite (Smart Dentin Replacement [SDR]) to several pulp-capping materials, including MTA Plus, Dycal, Biodentine, and TheraCal. Materials and Methods: Eighty acrylic blocks with 2-mm-deep central holes that were 4 mm in diameter were prepared and divided into 2 groups (n = 40 each) according to the composite used (Dyad Flow or SDR). They were further divided into 4 sub-groups (n = 10 each) according to the pulp-capping agent used. SBS was tested using a universal testing machine at a crosshead speed of 1 mm/min. Data were analyzed using 2-way analysis of variance. A p value of < 0.05 was considered to indicate statistical significance. Results: A statistically significant difference (p = 0.040) was found between Dyad Flow and SDR in terms of bond strength to MTA Plus, Dycal, Biodentine, and TheraCal. Conclusions: Among the 8 sub-groups, the combination of TheraCal and SDR exhibited the highest SBS.

• Journal of Korean Society of Rural Planning
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• v.15 no.4
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• pp.1-10
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• 2009

Rural amenity is regarded as a breakthrough that can revitalize the rural communities. The demand for rural amenity development is also increasing since the urban people have growing incomes and leisure time. This study was implemented to survey the needs and application directions of rural amenity database. The survey questionnaires were collected from various related groups including industry, universities, administration and research institute. Two kinds of analysis of variance (ANOVA) were carried out in order to prioritize the building rural amenity resource map among four user groups and ten rural amenity resources. The result of survey showed that most of respondents had been aware of amenity resources and the industry group had the highest level of utilization in making decisions for rural development. Although the significant difference among groups was not shown in the priority, the priority in the construction of information map was shown the significant difference among 10 kinds of amenity resources. Landscape's map and traditional resource map were relatively higher priority than the other resource map.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.5
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• pp.130-136
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• 2001

Generally, a metal slitting saw is plain milling cutter with thickness less than 3/16 inch. This is used for cutting a workpiece that high dimensional accuracy and surface finish is necessary. A small thin milling cutter like a metal slitting saw is useful for machining a narrow groove. In this case, built up edge(BUE) is severe at each tooth and affects the surface integrity of the machined surface and tool wear. It is well known that tool geometry and cutting conditions are decisive factors to remove BUE. In this paper, we optimized the geometry of the milling cutter and selected cutting conditions to remove BUE by the experimental investigation. The experiment was planned with Taguchi method based on the orthogonal array of design factors such as coating, rake angle, number of tooth, cutting speed, feed rate. Response table was obtained from the number of built-up edge generated at tooth. The optimized tool geometry and cutting conditions could be determined through response table. In addition, the relative effect of factors was identified bh the analysis of variance (ANOVA). Finally, coating and cutting speed turned out important factors for BUE.

• The Journal of Korean Physical Therapy
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• v.29 no.2
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• pp.80-84
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• 2017

Purpose: This study was conducted to examine the effects of different sizes of blood flow restriction areas on the thickness of the external oblique and biceps brachii. Methods: The study subjects were 52 adults who were divided into four groups that performed plank exercises over a six-week period after blood flow restriction. Changes in the thickness of the external oblique and biceps brachii were measured using ultrasonography before the experiment, then three and six weeks after the experiment. The changes in each variable over time were evaluated by repeated-measures analysis of variance (ANOVA). Results: The external oblique and biceps brachii showed significant differences in muscle thickness with regard to time and the interaction between time and each group (p<0.01), but no significant differences with regards to changes between groups (p>0.05). Conclusion: A larger blood flow restriction area resulted in a statistically significant increase in muscle thickness. The results of this study may be used as the basis for future studies and for rehabilitation in clinical practice.

• Journal of Pharmaceutical Investigation
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• v.24 no.2
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• pp.67-72
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• 1994

Bioequivalence (BE) test of biphenyl dimethyl dicarboxylate (DDB) tablets was performed. Normal healthy male volunteers (n = 20) were randomly divided into 2 groups, and reference $(Nissel{\circledR})$ and test $(Livital{\circledR})$ tablets of DDB $(25mg{\times}8\;Tab.\;= \;200\;mg)$ were given orally by balanced two-period cross-over design. The serum concentration was determined by high performance liquid chromatography. The pharmacokinetic parameters, AUC, $C_{max}$, and $T_{max}$ obtained after drug administration were statistically analyzed. Statistical evaluation of the data involved an analysis of variance (ANOVA) for cross-over design. The results were within 20% differences of mean value in AUC, $C_{max}$, and $T_{max}$ between reference and test tablets. The results of ANOVA showed no significant differences for "between group or subject" and "period". The test tablet was bioequivalent with the reference tablet in the AUC, $C_{max}$, and $T_{max}$.

• Journal of Korean society of Dental Hygiene
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• v.20 no.4
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• pp.525-533
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• 2020

Objectives: This study was conducted to facilitate improvements in career preparation behavior and career development of dental hygiene students by investigating the effects of self-leadership and career decision self-efficacy on the career preparation behavior of dental hygiene students. Methods: A self-reported questionnaire was filled out by 190 dental hygiene students between August 20 to October 31, 2019. The data were analyzed using SPSS 20.0. Independent t-test, one way ANOVA, the Scheffe posthoc test, and the Pearson correlation results were reviewed, and a multiple regression analysis was conducted. Results: Self-leadership, career decision self-efficacy, and career preparation behavior were scored 3.29, 3.36, and 2.91 points, respectively. The variables that influenced career preparation behavior were the motion of major select and self-leadership. These factors had 30.5% of variance among dental hygiene students. Conclusions: Institutional support, including counseling and leadership education by professors and students, is needed in schools to improve the career preparation behavior of students majoring in dental hygiene.

• The Journal of Advanced Prosthodontics
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• v.12 no.4
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• pp.204-209
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• 2020

PURPOSE. Prevention of xerostomia and stress is important to prolong healthy life expectancy and improve the quality of life. We aimed to investigate the effects of tongue rotation exercise for increasing salivary secretions and stabilizing salivary stress hormone levels. MATERIALS AND METHODS. Twenty four participants without subjective oral dryness were enrolled. The exercises comprised tongue rotation exercise and empty chewing. The salivary stress hormone level was measured using a Salivary Amylase Monitor. Unstimulated whole saliva volume and salivary amylase activity were measured before tongue rotation exercise or empty chewing and subsequently 5, 10, and 15 minutes after these exercises. Differences in the rates of change of unstimulated whole saliva volume and salivary amylase activity were analyzed by repeated measure analysis of variance. RESULTS. Statistically significant differences among the rates of change were not observed after empty chewing for unstimulated whole saliva volume and salivary amylase activity at the four measurement times. However, the rate of change of unstimulated whole saliva volume and salivary amylase activity were statistically significantly different among the four time points: before the tongue rotation exercise and 5, 10, and 15 minutes post-exercise (P<.05 and P<.01, respectively). CONCLUSION. Tongue rotation is effective in increasing saliva secretion, reducing stress, improving oral function, and extending healthy life expectancy.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.3
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• pp.21-27
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• 2018

In this paper the laminate design parameters are researched to maximize the performance index of a composite pressure vessel. To maximize the performance index, the three design variables that the thickness of each of helical and hoop layers and the length of hoop layer are considered under the assumption of fixed internal space. To optimize the variables, the response surface method is introduced for construction of the surrogate model and the ANOVA(analysis of variance) is performed to evaluate the effects of the variables. The optimization problem is formulated to maximize performance index under the burst pressure constraint. To verify the effectiveness of the research, numerical analyses are performed for the optimum model.