• Korea-Australia Rheology Journal
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• v.17 no.2
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• pp.79-85
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• 2005

Aqueous mixtures of hyaluronic acid and poly(vinyl alcohol) system and hydrogels thereof were introduced to obtain new bioartificial materials that have excellent mechanical properties, biocompatibility and enhanced rheological properties. The interactions between hyaluronic acid and poly(vinyl alcohol) and/or borax were investigated by rheological measurements. Preparation parameters of the aqueous mixtures were mixture composition, the degree of hydrolysis of poly(vinyl alcohol) and borax concentration. From the rheological behavior, it could be deduced that the key factor of the interaction between hyaluronic acid and poly(vinyl alcohol) was the hydrogen bonding between them and the effect was pronounced with borax. Enhanced viscosity was observed at the composition of $20wt\%$ of hyaluronic acid solution and $80wt\%$ of poly(vinyl alcohol) and borax solution. Rheological properties were influenced by the degree of hydrolysis of poly(vinyl alcohol) and borax concentration. As the degree of hydrolysis and borax concentration increased, rheological properties increased due to the increased hydrogen bonding and networking of hyaluronate aggregates. Physical hydrogels from hyaluronic acid and poly(vinyl alcohol) were prepared and the composition dependence of the gels was rheologically investigated as well.

• Bulletin of the Korean Chemical Society
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• v.13 no.2
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• pp.208-210
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• 1992

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.507-514
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• 2005

In this construction case study, Crushed stone under 100mm diameter was carried out a test compacted construction for subgrade in the 3rd. runway of the 2th Incheon International Airport Construction area. Conforming to specification needs a minimum rolling compacted number 10 for upper subgrade 100% compaction degree indicated in Federal Aviation Administration and $K_{30}{\geq}20kgf/cm^3$ in plate bearing test. $K_{30}$ to be acquired 100% compaction degree of upper subgrade is confirmed to about $31kgf/cm^3$ from correlation $K_{30}$ vs relative compaction degree.

• Biomedical Science Letters
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• v.25 no.2
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• pp.170-176
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• 2019

The objective of this study was to evaluate the characteristics of the mixtures of choline alphoscerate (alpha-glycerylphosphorylcholine, alpha-GPC), in the liquid form, and sucrose ester, which formed a solid composite. The choline alphoscerate solid composites were prepared using different ratios of sucrose ester, and different preparation methods, such as air drying and rotary evaporation, were compared for their preparation efficacy. We examined the characteristics of the solid composites by using scanning electron microscopy (SEM), angle of repose, and moisture content. The ideal mixing ratio of choline alphoscerate and sucrose ester was determined as 1:3 and air drying was found to be more suitable for the preparation of solid composites than rotary evaporation. SEM measurements of the degree of dispersion and the size of particles indicated that a high-temperature air method was more suitable. These results demonstrated the successful preparation of choline alphoscerate solid composites that have potential for industrial use.

• The Korean Journal of Community Living Science
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• v.20 no.2
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• pp.275-289
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• 2009

The purpose of this study is to examine the middle aged's perception of aging and the degree of physical/financial/social preparation for later life and to explore the effect of the middle aged's perception of aging, who live in Gwangju & Jeonnam of Korea, on physical/financial/social preparation for later life. This research also explores gender differences in perception of aging, preparation for later life and related factors. For the purpose, the survey data was gathered from 424 middle aged (40's & 50's) citizens who live in Gwangju and Jeonnam, using structured questionnaire. The statistical methods used for data analysis are descriptive statistics, cross tables, t-test, correlations and regression with Spss/win 17.0 program. The major findings of this study are as follows: Most of the respondents perceive that the age of being aged is 65 or 70 years old. Respondents feel anxiety about health (84%), finance (57%) and roleless role (22%) of later life. Female group feel health anxiety more than male group. Many people perceive that social preparation for later life is better than financial preparation and physical preparation for later life. The result shows that female group perceives their physical preparation level more positively than male group generally. But, there were no differences in financial and social preparation between gender groups. Finally, the result shows the meaningful relationships between male group's perception of aging and financial preparation for later life. Monthly income is the most important variable predicting preparation for later life.

• Journal of Families and Better Life
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• v.20 no.6
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• pp.141-149
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• 2002

In order to promote well-being during old age, it is important to start preparing early on for the later life. Based on this thesis, this study examined attitudes of the middle-aged women residing in rural towns on their preparation for old age as well as related variables. For this purpose, survey data from 200 individuals were analyzed using a SAS program. The overall degree of preparation for old age was quantified as about 67 points out of a 100 possible points. The variables that affected the level of preparedness include attitude toward using a paid nursing home ($\beta$=.23), type of agricultural work they engage in ($\beta$=-.21), who do you think is a supporter during your old age($\beta$=.20)］, type of decision-making in the household ($\beta$=.17). The explanatory power of such variables as standards of living ($\beta$=.18), family type ($\beta$=-.18), recognition of the entrance of old age ($\beta$=.17), and preparation behavior for old age ($\beta$=.15) were partially proved in three sub-areas (economical, emotional, and leisure areas) of preparation. The groundwork of this study could be used as basic materials to develop an educational program to improve the attitudes toward preparation for old age.

• Medical Lasers
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• v.9 no.1
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• pp.51-57
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• 2020

Background and Objectives For experiments on simulated burn, the preparation of an animal model is a very important step. The purpose of the current experiment is to design a simple and controllable method for the preparation of third-degree scald in a mouse model using the boiling water method. Materials and Methods A total of 18 Swiss mice were used. After the anesthetization, the mice were scalded by boiling water (100℃) using a mold with a 1 cm² circle area on the dorsum at contact times of 3s, 5s, and 8s. After confirming that 8 seconds of scald can cause a third-degree scald, the skin samples were collected at day 2, 4, 6, 8, 10, and 12, and analyzed by histopathological examinations. The wound retraction index (WRI) was also measured. Results Third-degree scald involving full-thickness skin was observed in the 8-second scald group, while a 3-second scald caused a superficial second-degree scald and a 5-second scald caused a deep second-degree scald. After third-degree scald, the burn wound continued to contract until day 14. Conclusion The scalding model of mice can be successfully established by the boiling water method. This method is easy to operate, it has a low cost, and it can control the scald depth by controlling the scald time. This is adequate to study skin thermal injury in the future. The scald model established by this method can last for 14 days.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.3
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• pp.51-59
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• 1997

Dissolving pulp is a low yield(30∼35%) bleached chemical pulp that has a high cellulose content (95% or higher) suitable for use in cellulose derivatives such as rayon, cellulose acetate. This research was studied for dissolving pulp preparation as the raw material of viscose rayon from commertial pulps. (TMP, CP, DIP) In the change of pulp(cellulose) characteristics after sodium hypochlorite and solvolysis treatment. the following results were obtained In the case of sodium hypochlorite pretreatment, we have obtained pulp that high purity cellulose, but degree of polymerization was inclined to decrease less than 170∼240. Comparing sodium hypochlorite pretreatment and solvolysis pretreatment, solvolysis pretreatment is superior to sodium hypochlorite process for making dissolving pulp. We think that the low degree of polymerization of cellulose because of increasing degradation of cellulose during delignification treatment.

• Journal of the Korean Wood Science and Technology
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• v.25 no.4
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• pp.45-50
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• 1997

This research was studied for dissolving pulp preparation as the raw material of viscose rayon from woody biomass by solvolysis pretreatment. In the change of pulp characteristic after solvolysis pretreatment, the following results were obtained. In the case of solvolysis pretreatment, we have obtained pulp that high purity cellulose, and degree of polymerization was inclined to decrease less than 440 on the phosphoric acid as catalyst. Comparing phosphoric acid and formic acid as catalyst in the solvolysis pretreatment, using on formic acid catalyst is superior to phosphoric acid catalyst for making dissolving pulp.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.137-145
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• 2021

The purpose of this study was to understand the degree of major satisfaction, nursing professional intuition, self leadership, and career preparation behavior of nursing college students, and to identify factors that influence career preparation behavior. Data were collected from 202 nursing college students in B city and analyzed by t-test, ANOVA, Pearson correlation coefficient, and multiple regression using SPSS/WIN 22.0. The degree of career preparation behavior in nursing college students was 3.16±.85. There were significant differences in career preparation behavior with respect to grade(t=-4.86, p<.001), college life satisfaction (F=11.82, p<.001). There was positive correlation between career preparation behavior and major satisfaction (r=.34, p<.001), nursing professional intuition(r=.24, p=.001), and self leadership(r=.54, p<.001). Factors affecting the career preparation behavior of the study subjects were self leadership(β=.491, p<.001), grade(β=.284, p<.001), college life satisfaction(β=.133, p=.039), and the explanatory power was 37.3%. Through this research requires the fellow study to determine the factors affecting career preparation behavior of nursing students.