• Women's Health Nursing
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• v.9 no.3
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• pp.287-298
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• 2003

Purpose: To explain the concept of postpartum weight retention and to analyze factor effect on it. Method: A total of 20 studies related postpartum weight retention were selected in the year of 1988-2001 and analysis was done. Result: A demographic factor like parity, age, social and economic level and life style such as exercise, diet, breast feeding are influential factor on postpartum retention weight. But parts of them don't agree the same results. Meanwhile, in some studies, psychological factor like women's self esteem related to postpartum retention weight, body image change, depressing is found to be very related. As a result, postpartum overweight gain could be a bad factor of physical and mental health. In Korea, we have few studies related to them. Conclusion: It is required to do many-sided and deep studies about aspects of postpartum retention weight and the factor that effect on it. Postpartum retention weight should be approached by controling weight from the period of pregnancy. And it would rather be researched through individual approach considered women's various demographic, social-cultural and physical level than be required standardized level of weight gain.

• Bulletin of the Korean Chemical Society
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• v.26 no.4
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• pp.629-633
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• 2005

In the reversed-phase chromatography, the retention time of sample was investigated based on the molecular structure of compound. Several descriptors that were related to retention factors were selected, and then the values of descriptors were calculated with several softwares. The effect of retention factor was measured with calculated values, and the results were obtained that each descriptors of molecular structure of compound have different effect on the retention factor. Therefore, the empirical equation for seven types of descriptors considered was obtained, and it has high values of correlation coefficient. Furthermore, the experimental data and calculated values have good agreement.

• Geomechanics and Engineering
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• v.28 no.1
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• pp.77-87
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• 2022

Many geotechnical analyses require the investigation of water flow within partially saturated soil zone to incorporate the effect of climatic conditions. It is widely understood that the hydraulic properties of the partially saturated soil should be included in the transient seepage analyses. However, the characteristics of dual porosity soils with dual-mode water retention curve are normally modelled using single-mode mathematical equation for simplification of the analysis. In reality, the rainwater flow can be affected significantly by the dual-mode hydraulic properties of the soil. This paper presents the variations of safety factor for dual porosity soil slope with dual-mode water retention curve and dual-mode unsaturated permeability. This paper includes the development of the new dual-mode unsaturated permeability to represent the characteristics of soil with the dual-mode water retention curve. The finite element analyses were conducted to examine the role of dual-mode water retention curve and dual-mode unsaturated permeability on the variations of safety factor under rainfall loading. The results indicate that the safety factor variations of dual porosity soil slope modelled using the dual-mode water retention curve and the unsaturated permeability equation are lower than those of dual porosity slope modelled using single-mode water retention curve and unsaturated permeability equations.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1807-1811
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• 2004

Supercritical fluid chromatography (SFC) was considered for separating racemic ibuprofen. The chromatographic column (3.9 ${\times}$ 150 mm) was packed with Kromasil$^{\circledR}$ CHI-TBB, and the mobile phase was supercritical carbon dioxide with modifier of IPA. The experimental variables were the content of IPA, and temperature and pressure of supercritical mobile phase. To determine the separation condition, the empirical equation of retention factor and resolution was proposed. In the case of retention factor, the empirical equation was in the form, $k\;=\;a{\rho}\;+b/F\;+\;c\;({\rho}/F)\;+\;d$. The empirical equation for resolution was proposed as a linear form, $R\;=\;a{\rho}\;+\;bF\;+\;c$.

• YAKHAK HOEJI
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• v.53 no.5
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• pp.281-285
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• 2009

The retention of solutes in reversed-phase high-performance liquid chromatography depends on their hydrophobicity. Although the retention behaviors of alkyl benzenes have been reported so far, quite a few authors have mentioned the retention behavior of alkyl benzenes with plural hydrophobicity parameters. In this sense, we were interested in the retention behaviors of alkyl benzenes having benzene moiety and increasing alkyl chain. In this study, we therefore investigated the retention behavior of alkyl benzenes in reversed-phase high-performance liquid chromatography in order to obtain information concerning the effects of the aromatic moiety and the carbon chain on the retention mechanism by comparing their capacity factor (k') in relation to the carbon chain length. The eluent acetonitrile ($CH_3CN$) showed high selectivity on alkyl benzenes, showing the high difference of capacity factor (${\Delta}log\;k'$) between toluene and octyl benzene. Indeed, the ${\Delta}log\;k'$ of 80% $CH_3CN$ represented 1.42- and 4.25-times longer than 90% MeOH and 60% THF, respectively. The hydrophobicity parameters, van der Waals volume, bond constant, partition constant, $\pi$-energy effect and enthalpy were evaluated with the capacity factor (k') of alkyl benzenes eluted on 80% CH3CN, 90% MeOH and 60% THF, respectively. The best eluent for predicting retention behavior of alkyl benzenes was 90% MeOH ($R^2$ 0.999). The three parameters, van der Waals volume, bond constant and partition constant were well coincident to log k' by increasing alkyl benzenes. However, $\pi$-energy effect and enthalpy were severely disagreeable. Taken together, van der Waals volume, bond constant and partition constant were a reliable parameters to predict the retention behaviors of alkyl benzenes on reversed-phase column.

• Journal of Korean Academy of Nursing Administration
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• v.22 no.2
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• pp.137-147
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• 2016

Purpose: This study was designed to examine effects of sense of calling, job satisfaction and organizational commitment on retention intention in nurses who are at the advanced beginner-stage. Methods: Participants were 199 nurses with 13 to 36 months' clinical career at hospital located in Busan, Korea. Data were analyzed using descriptive statistics, independent t-test, one-way ANOVA, Scheffe test, Pearson correlation, and Multiple regression. Results: Retention intention correlated positively with sense of calling (r=.43, p<.001), job satisfaction (r=.31, p<.001) and organizational commitment (r=.31, p<.001). Factors affecting the participants' retention intention were found to be statistically significant (F=21.96, p<.001). Total factor score accounted for 24.1% of retention intention. Out of the related factors, the most influential factor was 'goals/meaning', belonging to the sub-areas of the sense of calling and explaining 18.2% of retention intention, followed by organizational commitment and average monthly income in that order. Conclusion: The results of this study suggest a need to develop a management program that helps promote retention intention for nurses at the advanced beginner-stage by both improving their monthly income and outside conditions and, more importantly, raising their sense of calling, especially in association with the goals/meaning of their life.

• Journal of Korean society of Dental Hygiene
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• v.24 no.1
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• pp.27-33
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• 2024

Objectives: The purpose of this study was to examine factors affecting the retention intention of clinical dental hygienists. Methods: A total of 190 clinical dental hygienists were recruited as participants. Data were collected from March to May, 2023 and then analyzed using t-test, ANOVA, Pearson's correlation coefficient, and multiple regression through PASW Statistics 26.0. Results: Mean scores for job crafting, job satisfaction, positive psychological capital and retention intention were 3.22, 3.46, 3.57 and 3.46 respectively. Retention intention showed a significant relationship with positive psychological capital (r=0.299), job crafting (r=0.214), and job satisfaction (r=0.649). The results of the multiple regression analysis indicated that job satisfaction was the strongest predictor of retention intention, explaining 24.1% of the total variance (F=4.550, p<0.001). Conclusions: Variables that can affect the retention intention of clinical dental hygienists were identified, with job satisfaction emerging as a significant factor affect retention intention.

• Geomechanics and Engineering
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• v.33 no.2
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• pp.141-154
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• 2023

This study investigated the effect of water retention characteristics between aged and fresh Municipal Solid Waste (MSW) on the stability of the landfill. A series of transient numerical modeling for the slope of an MSW landfill was performed considering the variation of water retention characteristics due to leachate circulation. Four different scenarios were considered in this analysis depending on how to obtain hydraulic conductivity and the aging degree of materials. Unsaturated hydraulic properties of the MSW used for the modeling were evaluated through modified hanging column tests. Different water retention properties and various landfill conditions, such as subgrade stiffness, leachate injection frequency, and gas and leachate collection system, were considered to investigate the pore water distribution and slope stability. The stability analyses related to the factor of safety showed that unsaturated properties under those varied conditions significantly impacted the slope stability, where the factor of safety decreased, ranging between 9.4 and 22%. The aged materials resulted in a higher factor of safety than fresh materials; however, after 1000 days, the factor of safety decreased by around 10.6% due to pore pressure buildup. The analysis results indicated that using fresh materials yielded higher factor of safety values. The landfill subgrade was found to have a significant impact on the factor of safety, which resulted in an average of 34% lower factor of safety in soft subgrades. The results also revealed that a failed leachate collection system (e.g., clogging) could result in landfill failure (factor of safety < 1) after around 298 days, while the leachate recirculation frequency has no critical impact on stability. In addition, the accumulation of gas pressure within the waste body resulted in factor of safety reductions as high as 24%. It is essential to consider factors related to the unsaturated hydraulic properties in designing a landfill to prevent landfill instability.

• KSBB Journal
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• v.28 no.4
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• pp.254-259
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• 2013

Herein we present a diagnostic paper chip that can quantitatively detect albumin without external electronic reader and dispensing apparatus. We fabricated a diagnostic paper chip device by printing wax barrier on the paper and wicking it with citrate buffer and tetrabromophenol blue to detect albumin in sample solution. The paper chip is so simple that we dropped a sample solution at sample pad and measure the ratio of two travel distances of the sample solvent and albumin under the name of retention factor. Our result confirmed that the retention factor was constant in the samples with same concentration of albumin and useful determinant for the measurement of albumin concentration. The paper chip is affordable and equipment-free, and close to ideal point-of-care test in accordance with the assured criteria, outlined by the World Health Organization. We assume that this diagnostic paper chip will expand the concept of colorimetric determination and provide a inexpensive diagnostic method to aging society and developing country.

• Journal of the Korea Concrete Institute
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• v.11 no.3
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• pp.153-160
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• 1999

Water soluble hydroxyalkyl methycellulose ethers are used in a variety of applications incluing building industry as a supplementary agent used for incresing adhesives, water retention capacity, workability and viscosity modify. Water retention capacity(WRC) is the capability to contain water in the ploymer chain under condition of being mixed with cement. In general, the WRC is affected by the viscosity, the adding amount, the particle size, the rate of dissolving and the amount of substituted chemical in cellulose ethers. In the other words, WRC is increased as higher the viscosity, more adding amount, finer the particle size and longer the dissolving time of cellulose ethers. This thesis investigated each factor that effect the WRC, particularly the relation between degree of substitution(DS), molar of substitution(MS) and WRC. It is observed that WRC is not nearly affected by DS of cellulose ethers, but is changes proportionally as MS increases in the narrow range(0.10~2.25)