• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1319-1326
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• 2012

This study focuses on the influence of tractive forces on the self-stability of a bicycle. The eigen-value analysis of the self-stability of a passive rider control linear bicycle model can be used to analyze the self-stability. A linear bicycle model with front and rear driving forces is developed. The influence of tractive forces on the self-stability is identified by using the developed model. A nonlinear multi-body bicycle model is used to confirm the results of the linear analysis.

• Communications of the Korean Mathematical Society
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• v.21 no.4
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• pp.787-794
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• 2006

Two main results are presented in relation to subordination, self-decomposability and semi-stability. One of the result is that strict semi-stability of subordinand process by selfdecomposable subordinator gives semi-selfdecomposability of the subordinated process. The second result is a sufficient condition for any subordinated process arising from a semi-stable subordinand and a semi-stable subordinator to be semi-selfdecomposable.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.4
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• pp.391-401
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• 2009

The successful outcome of dental implants is mainly the result of intial implant stability following placement. The aim of this study was to investigate the effect of a self-tapping blades and implant design on initial stability of two tapered implant systems in poor bone quality. The two different implant systems included one with self-tapping blades and one without self-tapping blades. D4 bone model using Solid Rigid Polyurethane Form was used to simulate poor bone densities. The insertion torque during implant placement was recorded. Resonance frequency Analysis (RFA), measured as the implant stability quotient (ISQ), was assessed immediately after insertion. Finally, the implant-bone specimen was transferred to an Universal Testing Machine to measure the axial pull-out force. Insertion torque values and maximum pull-out torque value of the non self-tapping implants were significantly higher than those in the self-tapping group (P = 0.008). No statistically differences were noted between the two implant designs in RFA. Within the each implant system, no correlation among insertion torque, maximum pull-out torque and RFA value could be determined. Higher insertion torque of the non-self-tapping implants appeared to confirm higher clinical initial stability. In conclusion, implants without self-tapping blades have higher initial stability than implants with self-tapping blades in poor bone quality.

• Journal of the Korean Home Economics Association
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• v.32 no.4
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• pp.117-133
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• 1994

The purpose of this study was to investigate marital stability as a function of the couple's patterns of differentiation of self and family-of-origin emotional health. The subjects were 229 couples who have been married for 10 years or less living in Seoul and whose father or mother is still alive. The main results of this study were summarized as follows; 1. The couples which both husband and wife have high differentiation of self showed the highest marital satisfaction and marital stability. On the other hand, the couples which both husband and wife have low differentiation of self reported the lowest marital satisfaction and marital stability. 2. In general differentiation of self had more impact on both men's marital satisfaction and marital stability than women's

• Korean Journal of Childcare and Education
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• v.7 no.2
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• pp.61-79
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• 2011

The purpose of the study is to verify the relations of stability and aggression and level of self-esteem among adolescents. The participants were 306 highschool students in Suncheon, South Jeolla province, including 150 male students and 156 female students. Each participants completed a package of survey by questionnaire for Self-esteem scale, and stability and aggression scale. Followed are the major results; First, there were no gender differences in the level of self-esteem, but there were gender differences; girls were higher than boys in the stability of self-esteem. Second, the lower level of self esteem and the unstability adolescents had, the higher aggression they had. Third, Third, aggression of self-esteem was affected by self-esteem, and the relations between stability of self-esteem and gender. These findings have important implications that the verification of relations of stability and aggression helps self-esteem development for adolescents understand.

• Computers and Concrete
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• v.21 no.2
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• pp.111-116
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• 2018

Establishment of test methods to assess the fresh properties of self-compacting concrete (SCC) are required to ensure the homogeneity in fresh and hardened states. This paper discusses the suitability of a simple test method for assessing the slump flow and stability of SCC by testing on self-compacting mortar (SCM) fraction. The proposed test method aims at investigating slump flow diameter test and sieve stability test of SCC by testing SCM fraction with a plunger penetration apparatus. A central composite modeling design was performed to evaluate the effects of water/cement ratio (W/C), superplasticizer dosage (SP) and powder marble content (MP) on slump flow diameter, stability and plunger penetration test of fresh SCC. The responses of the derived statistical models are slump flow (Sf), sieve stability (S) and plunger penetration (P). Relationships obtained in this study show acceptable correlations between plunger penetration test value and slump flow diameter test results and stability. It should note that the developed relationships are very useful to predict slump flow diameter and stability of studied SCC mixtures by carrying out a simple plunger penetration test on its mortar, which can save labour and time in laboratory experiments.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.4
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• pp.443-450
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• 2014

In this study, we have discussed about the effect of hydrofoil arrangement and longitudinal moment characteristic on longitudinal motion stability of fully-submerged hydrofoil by the experiment of tandem hydrofoil model. First of all, tandem hydrofoil model that has canard wing arrangement has been made and characteristics of lift force and drag force by performing the lift force and drag force measuring experiment has also been estimated. Besides, tandem hydrofoil model's wing arrangement which has the initial stability and self stability of longitudinal motion has also been determined. In longitudinal stability experiment of tandem hydrofoil model, the motion characteristic of pitch and heave and the longitudinal stability of foil borne condition by variation of self stability of longitudinal moment and longitudinal distance are estimated. The result from the experiment and it's important conclusion can be described as below; Increase the self stability for longitudinal moment, the higher self stability for pitch motions in a constant pitch angles. By increasing the self stability for longitudinal moment, the range of fluctuation of pitch motion and heave motion for pitch angle also will change relatively small and longitudinal stability is excellent. Lastly, when the lift force of hydrofoil is remain constants, we can conclude that securing the enough self stability for longitudinal moment is essential for stable foil borne condition of tandem hydrofoil.

• Women's Health Nursing
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• v.17 no.5
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• pp.454-462
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• 2011

Purpose: This paper identified the effects of kangaroo care (KC) on maternal self-esteem and the growth and physiological stability of premature infants hospitalized in the neonatal intensive care unit. Methods: The experiment was conducted with an experimental group of 17 infants, and a control group of 17 infants selected by convenience sampling. KC was given to the infants one time a day for 30 minutes after feeding for two weeks. Their weight was measured every morning, and their physiological stability was measured in terms of their body temperature, respiratory rate, heart rate, oxygen saturation, and stability of the cardio-respiratory system in premature infants (SCRIP) score, as physiological responses at every 10 minutes during the intervention. Maternal self-esteem was assessed by a maternal self-report inventory. Results: The experimental group showed significant increase in the self-esteem of mothers. Also, KC was effective on physiological stabilization of preterm infants. Conclusion: This study suggests that KC can be provided in clinical settings more widely in Korea as one of the nursing interventions aimed at promoting maternal self-esteem as well as infants' physiological stabilization.

• Research in Community and Public Health Nursing
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• v.20 no.1
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• pp.23-30
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• 2009

This study was to identify the relationship among self-management, economic stability, self-esteem, self-achievement and predictor of the self-achievements in elders. Methods: A total of 294 subjects aged between 60 and 92 were selected through convenient sampling. Data were collected by self-reported questionnaire from May to June, 2008. Collected data were analysed by the SPSS/WIN 15.0 program. Results: Self-management, economic stability, self-esteem, self-achievement were positively correlated. The most significant predictor of self-achievement in elders were self-management and self-esteem. Conclusion: These findings suggest that self-achievement is influenced by self-management and self-esteem and needed for aged well

• The korean journal of orthodontics
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• v.47 no.1
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• pp.11-20
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• 2017

Objective: This randomized controlled trial aimed to compare the stability of mandibular arch orthodontic treatment outcomes between passive self-ligating and conventional systems during 6 months of retention. Methods: Forty-seven orthodontic patients with mild to moderate crowding malocclusions not requiring extraction were recruited based on inclusion criteria. Patients (mean age $21.58{\pm}2.94years$) were randomized into two groups to receive either passive self-ligating ($Damon^{(R)}$ 3MX, n = 23) or conventional system (Gemini MBT, n = 24) orthodontic treatment. Direct measurements of the final sample comprising 20 study models per group were performed using a digital caliper at the debonding stage, and 1 month, 3 months, and 6 months after debonding. Paired t-test, independent t-test, and non-parametric test were used for statistical analysis. Results: A significant increase (p < 0.01) in incisor irregularity was observed in both self-ligating and conventional system groups. A significant reduction (p < 0.01) in second interpremolar width was observed in both groups. Mandibular arch length decreased significantly (p = 0.001) in the conventional system group but not in the self-ligating system group. A similar pattern of stability was observed for intercanine width, first interpremolar width, intermolar width, and arch depth throughout the 6-month retention period after debonding. Comparison of incisor irregularity and arch dimension changes between self-ligating system and conventional system groups during the 6 months were non-significant. Conclusions: The stability of treatment outcomes for mild to moderate crowding malocclusions was similar between the self-ligating system and conventional system during the first 6 months of retention.