• Journal of Korean society of Dental Hygiene
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• v.23 no.1
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• pp.63-72
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• 2023

Objectives: This study aimed to identify the level of occupational and organizational retention intention and related factors among new dental hygienists. Methods: The participants were 195 dental hygienists employed for less than 24 months. A t-test and one-way analysis of variance were conducted to determine the level of intention to stay according to an individual's major-related characteristics and work environment awareness level. Pearson's correlation analysis was performed for each item, and stepwise multiple regression was performed for factors related to retention intention. Results: In the work environment, the organizational support network had the highest occupational retention intention (β=0.513). Organizational retention intention (β=0.351), working infrastructure (β=0.293), cooperation relationship (β=0.165), and management justice (β=0.151) were factors related to organizational retention intention (p<0.001). Employment at the practice hospital was related to occupational (β=0.167) and organizational retention intention (β=0.138), and satisfaction with clinical practice was related to occupational retention intention (β=0.327). Conclusions: New dental hygienists are expected to be actively utilized for long-term tenure in both occupations and organizations by actively reflecting on the results obtained through this study in the curriculum and working environment of dental hygienists.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.4
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• pp.566-580
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• 1998

Implant-supported overdenture is known as a useful appliance, instead of using the conventional complete denture, for better retention and stability. In this study 4 types of materials such as, gold bar/plastic clip(group AuP), gold bar/metal clip(group AuM), palladium bar/plastic clip(group PdP), and palladium bar/metal clip (group PdM) were used to evaluate the retention forces according the type of clips and alloys used for bar fabrication, in the Hader bar system. Repeated insertions and removals of overdenture were conducted in each group. and the retention forces were measured and compared the data of each group according to the number of insertion and removal. The obtained results were as follows, 1. In the comparison of retention forces according to type of bar-clip, retention was increased in the order of group AuM, PdM, PdP AuP. and the retention force of group AuM was significantly increased compared with those of others (p<0.05). 2. In the comparison of retention forces according to the number of insertion, only group PdP showed significant decrease in retention(p<0.05). 3. In the comparison of retention forces according to the type of bar and clip. there was no significant difference in the type of bar, but the retention of plastic clip was significantly higher than that of metal clip when Au bar was used(p<0.05). 4. In the observation of the bar surface, group AuM using Au bar and metal clip showed the most scratches among bar groups.

• Health Policy and Management
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• v.22 no.3
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• pp.365-382
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• 2012

Background : Public hospitals suffer worsening shortage of physicians and face great pressure of recruiting doctors. This study is aim to identify the factors associated with retention of physicians who are working in public hospitals. Methods : We conducted a cross-sectional and self-administered questionnaire survey in July, 2011. A total of 333 physicians responded from the 31 public hospitals. We analyzed the difference of job retention across the variables among doctors stratified as salaried and public health doctors. We used chi-square test and multiple logistic regression analysis. Results : To the salaried doctor, longer work period(OR=2.04 in 3rd quartile), professional autonomy(OR=2.69), and positive attitude toward public health(OR=2.39) affect to the higher job retention whereas complain of low income(OR=0.33) and complain of poor clinical environment(OR=0.26) affects to the lower job retention. To the public health doctors, community connections such as hometown(OR=6.27), spouse factors(OR=3.49), and positive attitude toward public health(OR=3.19) affect to the higher job retention. But longer work period(OR=0.17 in 3rd quartile) affects to the lower job retention. Conclusions : Associated factors of job retention vary across physician's status. Professional autonomy has major impact on the job retention to the salaried doctor. And familial factors as well as community relationship have greatest impact to the public health doctor. Positive attitude toward public health is associated with the higher job retention to the both of salaried and public health doctors.

• Elastomers and Composites
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• v.39 no.3
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• pp.209-216
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• 2004

Two types of polyurethane-acrylate polymer were synthesized by reaction of 2-hydroxyethyl methacrylate(HEMA), acrylamide(AA), and polyurethane prepolymer. Water-soluble cationic polyurethane/acrylate retention aids were prepared by using polyurethane-acrylate, benzyl chloride and distilled water. The retention, drainage and strength properties of the retention aids were investigated. The retention of cationic polyurethane/acrylate type retention aids maintained around 70 % regardless of nm. COD value of white water was much reduced by adding the retention aids to it. Drainage property was also improved by addition of the retention aids. In addition, specific compression strength of the paper was improved a little by addition of the retention aids. PU-HEMA type showed better performance than PU-AA in terms of compression strength of the paper.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.2
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• pp.1-7
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• 2001

Use of high yield pulp and recycled fiber as raw materials and water system closure result in higher fines content and buildup of organic and inorganic contaminants in white water. These are detrimental for the effectiveness of chemical additives including retention aids. Thus it is imperative to employ a retention systems that maintains its efficiency in closed papermaking system for reducing fresh water consumption. The performance of four different microparticle retention systems including cationic polyacrylamide (C-PAM)/bentonite, highly charged cationic starch (HCS)/silica, C-PAM/micropolymer, cationic guar gum (CGG)/silica was evaluated and compared at three different levels of papermaking system closure. Buildup of detrimental substances in a closed white water system increased cationic demand and finally reduced the performance of retention systems. Cationic starch and guar gums maintained their effectiveness in retention in closed white water systems contaminated with anionic trashes because of their structural rigidity and hydrogen bonding ability. Particularly, cationic guar gums, due its stiffness of molecular structure, appeared perform better than catinonic starch.

• English Language & Literature Teaching
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• v.18 no.2
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• pp.67-84
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• 2012

The present study investigated the effect of sentence translation as a production task on short-term and long-term retention of foreign vocabulary. 87 EFL university students at a beginning level, enrolled in reading class participated in the study. The study compared the performance of three groups on vocabulary recall: (1) Control group, (2) Translation group, and (3) Copy group. During the treatment sessions, translation group translated L1 sentences into English, while copy group simply copied given English sentences with each target word. Results of the immediate test were collected each week from week 2 to week 5 and analyzed by one-way ANOVA. Results revealed that regarding short-term vocabulary retention, participants in rote-copy condition outperformed those in translation group. Four weeks later a delayed test was administered to measure long-term vocabulary retention. In contrast, the results of two-way repeated measures ANOVA showed that long-term vocabulary retention of translation group was significantly greater than copy group. The findings suggest that although sentence translation is rather challenging to low-level learners, it may facilitate long-term retention of new vocabulary given the more elaborate and deeper processing the task entails.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.2
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• pp.1-7
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• 2008

The trend of using more hardwood and recycled fibers, and closing more tightly of the paper mill white water system has resulted in build-up of fines as well as organic and inorganic contaminants in the white water. This changes in papermaking wet end requires developing chemical additive system that provides good fiber retention and drainage in closed white water system. In this study the effect of charge densities and chemical characteristics of microparticle systems consisted of cationic guar gums and anionic colloidal silica sols on drainage and retention have been examined. Results showed that higher charge density of cationic guar gum and anionic colloidal silica sol gave better retention and drainage. Particularly highly structured silica gave greater retention efficiency.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.251-256
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• 2006

The purpose of this study was to confirm multiple retention system of C-PAM, A-PAM and Inorganic micro particles vs. traditional micro particle system and dual polymer system by measuring retention, drainage and formation using RDA HSF and Techpap 2D -F Sensor The benefits of dual polymer system were easy to use, low chemical consumption and good retention property but defect was worse drainage property than inorganic microparticle systems. On the other hand, Inorganic microparticle system had benefit of good drainage effect but defects were difficult to use, high chemical consumption. Therefore, we tried to find optimal morphology of polyacrylamide and applied to multiple retention system of C-PAM, A-PAM and inorganic microparticles to compensate defects of both of retention systems. As a result, we found the performance of branched C-PAM, branched A-PAM and inorganic micro particle triple system was more appropriate than traditional inorganic mircoparticle systems or dual polymer systems by comparing retention, drainage and formation.

• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.979-984
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• 2008

In this study, 8 solutes (aniline, caffeine, p-cresol, ethyl benzene, methylparaben, phenol, pyridine, and toluene) have been tested in terms of linear solvation energy relationships (LSER). Several micellar liquid chromatography (MLC) systems using cationic surfactant cetyltrimethylammonium bromide (CTAB) and a mixture of water with (methanol, n-propanol, and n-butanol) modifiers were characterized using the LSER solvation parameter model. The effects of the surfactant and modifier concentration on the retention in MLC were discussed. LSER model had demonstrated high potential to predict retention factors with high squared correlation coefficients ($r^2$ > 0.99). A comparison of predicted and experimental retention factors suggests that LSER formalism is able to reproduce adequately the experimental retention factors of the solutes studied in the different experimental conditions investigated. This model is a helpful tool to understand the solute-surfactant interactions and evaluate the retention characteristic of micellar liquid chromatography.

• Bulletin of the Korean Chemical Society
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• v.13 no.3
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• pp.240-245
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• 1992

The effect of the addition of sodium dodecyl sulfate (SDS) to a buffered mobile phase (pH 3.4) on the retention of nucleotides, nucleosides and bases was investigated with a polyvinyl alcohol (PVA) column. Depending on the concentration of SDS, two different trends in the retention of nucleosides and bases containing an $NH_2$ group were observed. If the concentration of SDS was less than 5.5 mM, the retention of compounds containing an $NH_2$ group increased as the concentration of SDS in the mobile phase increased. In contrast, if the concentration was greater than 5.5 mM, the retention of compounds containing an $NH_2$ group decreased. Thus, the SDS acted as an ion-pairing reagent at lower concentration but formed micelles at higher concentrations. The retention behavior of the nucleosides and bases in the presence of a micellar concentration of SDS in the mobile phase on the PVA column was compared to the retention behavior on other types of columns.