• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.05a
• /
• pp.221-226
• /
• 2005

In this paper, a dynamic model for the rotor shaft-coupling-blade system is developed. The blades are attached to a disk and driven by an electric motor shaft which is flexible in torsion. We assumed that the shaft torsional flexibility is lumped in the flexible coupling which is usually adopted in rotor systems. The Lagrangian approach with the small deformation theory for both blade-bending and shaft-torsional deformations is employed for developing the equation of the motion. The assumed modes method is used for estimating the blade transverse deflection. The numerical results highlight the effects of both structural damping of the system and the torsional stiffness of the flexible coupling to the dynamic response of the blade. The results showed strong coupling between the blade bending and shaft torsional vibrations in the form of inertial nonlinearif, stiffness hardening and softening.

• Korean Journal of Human Ecology
• /
• v.18 no.1
• /
• pp.137-143
• /
• 2009

The purpose of this study is to examine the evaluation of texture image and preference according to the structural characteristics of silk fabric, and to analyze the effects of texture image and sensibility on the preference. 53 female subjects evaluated fabric image and sensibility of 17 specimens of white silk fabrics sold on the market with semantic differential scale. The data were analyzed through factor analysis, Pearson correlational coefficient and t-test using SPSS win 13.0. For the evaluation, structural characteristics such as fiber contents, weave type, weight and thickness were analyzed. Factor analysis showed that sensibilities were classified into 3 categories; 'surface property', 'weight', 'flexibility'. Fabric images were classified into 2 categories; 'elegance' and 'naturalness'. Statistically significant differences of structural characteristics on the texture image were observed. Weave type affected 'surface property' and fiber contents affected' flexibility'. Weight and weave type affected' elegance', too. The significant factors affecting preference were fabric image of 'elegance' and structural characteristics of 'weave type'. The results of this study showed that the most preferred silk fabric is smooth and soft satin weaved fabric with texture image of 'elegance'.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.24 no.3
• /
• pp.429-439
• /
• 2000

This study was aimed to investigate the handle and mechanical properties of silk woven fabrics according to the fabric structure and yarn types 56 male and female students evaluated 16 black specimens with semantic differential scale of 20 hand adjectives. Mechanical parameters such as surface properties, bending properties and compression properties were tested using by KES-FS system. Data were analyzed through factor analysis, pearson correlation coefficient and t-test using PC SAS package. The results were as follows: The hand adjectives were grouped as 4 'surface roughness', 'flexibility', ;sense of thermal', and 'dryness'. 'Surface roughness' was highly sensed at satin fabrics of hard-twist yarn, noil yarn and spun yarn, while it was not at the fabrics of normal satin and twill at all. 'Flexibility' was reverse to 'surface roughness'. Thermal sense was felt highly at satin fabrics of noil-yarn, while low at plain fabrics of normal yarn. 'Dryness' was high at satin fabrics of hard-twist yarn and while it was low at normal satin fabrics. Predicted equations for subjective hand from mechanical properties of fabrics were developed using Stevens's law and stepwise regression and the coefficients of determination were high.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.15 no.9 s.102
• /
• pp.1023-1029
• /
• 2005

In this paper, a dynamic model for the rotor shaft-coupling-blade system was developed. The blades are attached to a disk and driven by an electric motor shaft which is flexible in torsion. We assumed that the shaft torsional flexibility was lumped in the flexible coupling which is usually adopted in rotor systems. The Lagrangian approach with the small deformation theory for both blade-bending and shaft-torsional deformations was employed for developing the equation of the motion. The Assumed Modes Method was used for estimating the blade transverse deflection. The numerical results highlight the effects of both structural damping of the system and the torsional stiffness of the flexible coupling to the dynamic response of the blade. The results showed strong coupling between the blade bending and shaft torsional vibrations in the form of inertial nonlinearity, stiffness hardening and softening.

• Research in Community and Public Health Nursing
• /
• v.18 no.4
• /
• pp.601-610
• /
• 2007

Purpose: This study investigated attitudes toward general elders and elders with dementia among nursing students before beginning the clinical practicum. In addition, students' characteristics differentiating the attitudes were examined. Methods: Attitudes were measured with questionnaires developed for Asian culture at the beginning week of the first semester of the junior year in two baccalaureate programs. Responses from 120 out of 121 students were analyzed using Pearson correlation coefficient, paired t-test, ANOVA, and Scheffe test. Results: Students held negative attitudes toward both types of elders except for generosity dimension toward general elders showing a neutral attitude. Elders with dementia were evaluated more negatively than general elders in all the dimensions of vitality, generosity and flexibility. Vitality and generosity toward general elders were different according to intimacy and the degree of communication with elders. Generosity toward general elders was also different according to students' religious beliefs. Students with interest in elders/issues showed more negative attitudes of vitality and flexibility toward elders with dementia. Conclusions: Students in general had negative attitudes toward elders and more negative attitudes toward elders with dementia. We need to put more efforts into the entire nursing curriculum in order to improve attitudes toward elders with particular concern over attitudes toward elders with dementia.

• Physical Therapy Korea
• /
• v.19 no.4
• /
• pp.46-54
• /
• 2012

Ely's test is commonly used to assess rectus femoris muscle flexibility. however, a reliability limit of this test was demonstrated by a previous study. In this study, we present an alternative method using an application for a digital horizontal level in a smartphone (DHLS) to complement the reliability limit of Ely's test. The aim of this study was to examine the reliability of Ely's test using DHLS on the pelvis, compared to using visual observation (VO) of pelvic and hip motions. Nineteen patients with lumbar extension-rotation syndrome were recruited for this study. An examiner examined the rectus femoris flexibility (both pass/fail and goniometer scoring) through Ely's test using both DHLS and VO. A retest session was completed two hours later for within-day reliability and seven days later for between-day intra-rater test-retest reliability. Results showed higher Kappa values for pass/fail scoring and higher intraclass correlation coefficient values for goniometer scoring in Ely's test using DHLS, compared to using VO. Measurement error and Bland and Altman plots further demonstrated the degree of intra-rater variance during Ely's test using DHLS in a clinical setting, compared to using VO. These results demonstrated that Ely's test using DHLS showed acceptable reliability compared to using VO. Ely's test using DHLS could be widely used for measuring the rectus femoris muscle flexibility in patients with lumbar extension-rotation syndrome, although the inter-rater reliability needs to be established first.

• East Asian Economic Review
• /
• v.25 no.3
• /
• pp.273-309
• /
• 2021

The development of regulatory systems varies between transition and non-transition economies. This suggests that they provide different incentives for entrepreneurial development and could have varied effects on the economy because they have different methods to deal with market failure. However, limited empirical evidence exists to prove the assumption of dichotomy. Using comprehensive data for institutional quality, labor market and financial market development, this research sought to analyze their effect on employment growth at micro level. The results show that the quality of institutions in transition economies are poorer relative to those in non-transition economies, but their financial and labor markets are more developed than the latter. Further analysis for the transition sample shows that the three variables are individually positively related with employment growth. For the non-transition sample, institutional quality and labor market flexibility bear a positive and significant effect on employment. Financial market development enters the model with a negative coefficient when regressed alone, but a joint test of significance finds that all the variables have a positive effect on employment growth. This result could imply that there is interdependence between institutional quality, labor flexibility and financial market development in firm-employment-growth relationship, or complementarity between regulations and the quality of institutions. Alternatively, this finding suggests that a stringently regulated credit market in non-transition economies have a selection effect-allocating credit only to entrepreneurs who already demonstrate strong growth potential. In sum, despite differences in the evolution of regulatory environment between the two samples, both of them complement employment growth at firm level. The overall implication of these findings is that less rigid regulations and coherent policies that are enforced with impartiality provide incentives for firms to expand.

• Journal of Fashion Business
• /
• v.16 no.1
• /
• pp.41-51
• /
• 2012

Polyester is mainly used as a bedding filler material. PLA fiber as an eco-friendly material for substituting polyester has a low melting temperature and therefore a hardening process is impossible. This study is to develop the oil for feather touch that can treat at the melting temperature of PLA. The slippery and soft aminosilicone emulsion, and the bulky epoxysilicone emulsion were used. They had proper viscosity and particle size for flexibility and elasticity. When using methoxy aminosilane [$H_2NSi(OCH_3)_3$] as an aminosilane and [$Zn(OCOCH_3)_2$] as a catalyst, the hardening reaction was fast and effective. Feather touch process were treated by 2 steps. At first step, aminosilicone emulsion, epoxysilicone emulsion and methylaminosilane were mixed and homogenized, and at second step, 5% blened solution of the first step, Zn catalyst 1%, distilled water 94% were treated at PLA fiber. After treatment the static friction coefficient and dynamic friction coefficient were reduced to 23.5-60.8% and 30.0-61.3% respectively, and the laundry and sun light fastnesses have not shown any decrease.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.19 no.1
• /
• pp.13-19
• /
• 2015

This paper presents the performance improvement of an EQS (Eradic Quake System) device applied to a nuclear power plant. For the nuclear facility, the EQS device needs to be ensured to have high quality, flexibility of design and reliability. To improve the reliability of the design, the hysteresis of the device must be exactly predicted. The friction coefficient of PTFE (PolyTetraFluoroEthylene) and the stiffness of the MER-Spring are considered as the factors influencing the hysteresis curve. In this paper, those factors are analysed to predict the behavior of the device and to improve the equipment of the EQS device. The results of the improved EQS device have been verified via a tests to be comparable with the predicted results. The estimation results indicate that considering those factors is more appropriate than the results of the previous design and method.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.27 no.4
• /
• pp.313-320
• /
• 1991

The paper describes the formulation for the analysis of the flexural free vibration of rectangular plate structure by the transfer influence coefficient method, which was developed on the base of the concept of the successive transmission of dynamic influence coefficients. For the analysis of rectangular plate which two opposite sides are simply-supported edge condition, the results of simple numerical examples demonstrate the validity of the present method, that is, the numerical high accuracy, the high speed and the flexibility for programming, compared with results of the transfer matrix method and exact solution or Leissa's method.