• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.95-98
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• 2006

This study investigates spalling properties of high performance concrete, 60MPa clan, made with the various types of coarse aggregate and adding ratio of polypropylene(PP) fiber. As experimental parameters, totally sixteen specimens of ${\phi}100{\times}200mm$ in size are prepared: one specimen for control without fiber, ten specimens with different coarse aggregate types, along with 0.05, 0.1, 0.15 percent of PP fiber in each. 1 hour fire test is conducted and then spalling appearance, spalling degree and residual compressive strength are examined. In addition, sit specimens made with two types of coarse aggregate site, along with same adding ratio of fiber are supplementally done, and only spalling properties is examined. Test results showed that control concrete and most specimens containing 0.05% of PP fiber exhibited 4 to 3 level of spalling degree, resulting severe explosive spalling, except for the specimen using basalt aggregate(Bc) showing 2 to 3 level of that. Especially, the Bc specimen containing 0.1% of the fiber exhibited that residual compressive strength value was 32%, which is 10% higher than other specimens using limestone or granite. Spalling resistance performance was also effective as aggregate size increase.

• Fashion & Textile Research Journal
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• v.11 no.1
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• pp.147-155
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• 2009

This study has been made to examine the basic information, the preferences of material quality, and the demand performance of clothing for underwear materials between atopic patients and non-patients. The measurement tool was a questionnaire. For statistical analysis of data, crosstabs, ${\chi}^2$-test, t-test and ANOVA through SPSS for Windows(version 14.0) were used. The results obtained are as follows. The degree of the basic knowledge about clothing materials indicated that women was higher than men. The material decision method and the most considering part in case of selecting underwear products showed difference between men and women. The preference factors for underwear material quality were drawn with the five factors of sense of weight/pliability, lustering/see-through, tactility, and sense of cold and warmth. The preferred underwear material showed difference according to gender, existence and nonexistence of atopic determatitis, and degree of strength of skin itching caused by clothing materials. The demand performances of clothing in case of selecting underwear were drawn with the four factors of hygiene/practicality, skin protection, quality of materials, and aesthetic attribute. The demand performance of underwear showed difference according to gender, existence and nonexistence of atopic determatitis, degree of strength of skin itching caused by clothing materials.

• The Journal of Korean Academic Society of Nursing Education
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• v.23 no.1
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• pp.66-75
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• 2017

Purpose: The aim of this study was to evaluate differences of pre-post simulation training in problem solving ability, performance confidence, and critical thinking skill according to degree of nursing students' self-leadership. Methods: This study was a descriptive survey using a self-report questionnaire. One hundred eighty nursing students participated in this study which programed a simulation scenario of pre-post operative patients' care. Descriptive statistics, paired t-test, ANCOVA with IBM SPSS 21.0 program were used for data analysis. Results: After the simulation training, both the above-average subjects and below-average subjects in self-leadership significantly improved their problem-solving ability, performance confidence, and critical thinking skill. compared with their previous level. The subjects who rated above-average in self-leadership, improved their degree of problem-solving ability, performance confidence, and critical thinking skill significantly more than those who were below-average in self-leadership. Conclusion: Self-leadership of nursing students is an important element in effective simulation training.

• Structural Engineering and Mechanics
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• v.85 no.3
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• pp.407-417
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• 2023

Precast assembled bridge piers with hybrid connection (PASP) use both tendons and socket connections. To study the seismic performance of PASP, a full-scale in-situ test was performed based on an actual bridge project. The elastic-plastic fiber model of PASP was established using finite element software, and numerical analyses were performed to study the influence of prestress degree and socket depth on the PASP seismic performance. The results show that the typical failure mode of PASP under horizontal load is bending failure dominated by concrete cracking at the joint between the column and cushion cap. The cracking of the pier concrete and opening of joints depend on the prestress degree and socket depth. The prestressing tendons and socket connection can provide enough ductility, strength, restoration capability, and bending strength under small horizontal displacements. Although the bearing capacity and post yield stiffness of the pier can be improved to some extent by increasing the prestressing force, ductility is reduced, and residual deformation is increased. Overall, there are reasonable minimum socket depths to ensure the reliability of the socket connection.

• The Journal of the Korea Contents Association
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• v.14 no.7
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• pp.291-301
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• 2014

This study is a descriptive research of investigating the correlation between new nurses' nursing performance, emotional intelligence, self-resiliency and core self-evaluation. The subjects were 114 new nurses working for less than 12 months at two different hospitals with over 800 beds located in Gyeonggi-do. Between July and November, this study collected the data measured by using a structured questionnaire survey for nursing performance, emotional intelligence, self-resiliency and core self-evaluation. As a result, it was found that there was a difference in the degree of nursing performance according to new nurses' education level, job satisfaction, and working position task satisfaction, and that the higher the emotional intelligence, self-resiliency and core self-evaluation were, the better the nursing performance was. As for emotional intelligence, education level, core self-evaluation and job satisfaction, it was found that they were variables to well predict the degree of nursing performance, and explained 33% of variance in nursing performance. Accordingly, it is necessary to provide actual field-adaptive training education including emotional intelligence and core self-evaluation other than nursing performance from new nurses' orientation in consideration of education degree and job satisfaction.

• Journal of Distribution Science
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• v.14 no.9
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• pp.31-45
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• 2016

Purpose - This study develops a simulation model that looks at the dynamics between social capital and business performance in strategic networks to understand their behaviors in relation to each other, and to suggest dynamic relationship strategies. Research design, data, and methodology - Based on existing literature, this study identifies the complex causal loop diagram on social capital and business performance in strategic networks, and converts them into a simulation model for observing how the changes in business environment and relationship dependency affect social capital and business performance. Results - The simulation results showed that, first, the formation in social capital and business performance of networks with low relationship dependency was less affected by the changes in business environment. Second, the formation in social capital and business performance of networks with high relationship dependency was negatively impacted by the changes in business environment. In other words, higher relationship dependency strengthened the impact of changes in business environment on business performance. Conclusions - Thus, this study confirmed that in strategic networks, the changes in business environment and the degree of relationship dependency dynamically affect business performance, and that relationship dependency mediates the degree in which changes in the business environment affect business performance. The results of the simulations were further verified through actual business cases.

• Asian Journal of Innovation and Policy
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• v.7 no.3
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• pp.461-488
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• 2018

This paper explores the relationship between network cooperation, innovation, internationalization and economic performance of manufacturing small and medium enterprises (SMEs) of engineering goods industry located in Bangalore city, India. At the outset, it is observed that SMEs receive the maximum assistance in the realm of product specifications. Moreover, they do not resort to manufacturing new products as much as they resort to product modifications or process improvements. Further, it is found (using Chi-square test of independence) that higher the network assistance received from an external network, greater is the innovation performance of SMEs. Subsequently, using analysis of variance (ANOVA), export intensity (proxy for internationalization performance) of SMEs is found to have a significant positive association with both the degree of their network cooperation and of their innovation performance. Lastly, it is observed that higher the degree of each of network cooperation, innovation performance and internationalization performance, better is the economic performance (measured by total sales turnover) of SMEs. These results have significant implications for the policy makers of the country to give due attention to network cooperation, innovation and internationalization as the means of enhancing the economic performance of SMEs.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5A
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• pp.317-325
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• 2012

In this study, to evaluate the shrinkage behavior of ultra high performance fiber reinforced concrete (UHPFRC) under restrained condition, restrained shrinkage test was performed according to ring-test mostly used at home and abroad. Ring-test was performed with the various thicknesses and radii of inner steel ring to give different degree of restraint. Free shrinkage and tensile tests were carried out simultaneously to estimate the degree of restraint, stress relaxation, and shrinkage cracking potential. Test results indicated that the average steel strain and residual tensile stress were reduced as the thicker inner steel ring was used, whereas degree of restraint was increased. The steel strain, residual tensile stress and degree of restraint were hardly affected by the size of radius of inner ring. In the case of all ring specimens, shrinkage crack did not occur because the residual tensile stress was lower than the tensile strength. About 39~65% of the elastic shrinkage stress was relaxed by the sustained interface pressure, and the maximum relaxed stress was increased as the thicker inner ring was applied. Finally, the degree of restraint with age was predicted by performing non-linear regression analysis, and it was in good agreement with the test results.

• Korean Journal of Biological Psychiatry
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• v.22 no.3
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• pp.140-148
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• 2015

Objectives The aim of this study is to investigate the correlation between degenerative changes in brain [i.e., global cortical atrophy (GCA), medial temporal atrophy (MTA), white matter hyperintensities (WMH)] and neurocognitive dysfunction in Korean patients with Alzheimer's disease. Methods A total of 62 elderly subjects diagnosed with Alzheimer's disease were included in this study. The degenerative changes in brain MRI were rated with standardized visual rating scales (GCA or global cortical atrophy, MTA or medial temporal atrophy, and Fazekas scales) and the subjects were divided into two groups according to the degree of degeneration for each scale. Cognitive function was evaluated with Korean version of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD-K) and several clinical features, including apolipoprotein E ${\varepsilon}4$ status, lipid profile and thyroid hormones, were also examined. Chi-square test and Fisher's exact test were performed to analyze the relationship between the degree of cerebral degeneration and neurocognitive functions. Results Demographic and clinical features, except for the age, did not show any significant difference between the two groups divided according to the degree of cerebral degenerative changes. However, higher degree of GCA was shown to be associated with poorer performance in verbal fluency test, word list recall test, and word list recognition test. Higher degree of MTA was shown to be associated with poorer performance in Mini-Mental State Examination in the Korean Version of CERAD Assessment Packet (MMSE-KC), word list recognition test and construction praxis recall test. Higher degree of white matter hyperintensities was shown to be associated with poorer performance in MMSE-KC. Conclusions Our results suggest that severe brain degeneration shown in MRI is associated with significantly poorer performance in neurocognitive tests in patients with Alzheimer's disease. Moreover, the degree of GCA, MTA and white matter hyperintensities, represented by scores from different visual rating scales, seems to affect certain neurocognitive domains each, which would provide useful information in clinical settings.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.5
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• pp.580-585
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• 2012

In this paper, the cycle performance analysis for condensation and evaporation capacity, total work and efficiency of ocean thermal energy conversion power system using R744 ($CO_2$) is presented to offer the basic design data for the operating parameters of this system. The operating parameters considered in this study include superheating and subcooling degree, evaporation and condensation temperature, pump and turbine efficiency. The main results were summarized as follows : The evaporation capacity of R744 increases with superheating and subcooling degree, but decreases with the increasing condensation temperature. The total work increases with superheating and subcooling degree of R744, but decreases with the increasing evaporating temperature. And, the efficiency increases with subcooling and superheating degree, but decreases with the increasing condensation temperature. Therefore, superheating and subcooling degree, evaporation and condensation temperature and pump and turbine efficiency of R744 OTEC power system have an effect on the evaporation and condensation capacity, total work and efficiency of this system. With a thorough grasp of these effect, it is necessary to design the OTEC power cycle using R744.