• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.93-99
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• 2019

The purpose of this study was to investigate the bond strength between PEKK(Polyetherketoneketone) and Sinfony(3M ESPE, Seefeld, Germany) the dental composite resin by proposing the three representative surface treatment methods and evaluate to see if they affect the bond strength between two materials. A total of 30 PEKK($Pekkton^{(R)}$ Ivory, $Cendres+M{\acute{e}}taux$, Bienne, Switzerland) specimens were prepared, embedded in acrylic resin, polished(P 1200 grid) to surface, and each group was divided into 10 specimens. After then, by the surface treatment method, it classified into three groups(n=10) such as Air abrasion group(PN), applying Single Bond Universal(3M ESPE) after Air abrasion(PB), applying OPAQUE(3M ESPE) after Air abrasion(PO). Then, veneering was performed by using Sinfony(3M ESPE, Seefeld, Germany). All completed specimens were allowed to rest in a $37^{\circ}C$ water bath for 24 hours. Shear bond strength of each group was measured and fracture patterns were classified. Statistic analysis was performed with One-way ANOVA followed by post hoc Scheffe tast (p<.05). Statistical analysis was performed using the SPSSWIN 21.0 program. As a result of one-way ANOVA, the average value of PB group was $27.67{\pm}4,18MPa$ and it was shown as the highest bond strength, PN and PO were $20.43{\pm}1.70$ and $19.8{\pm}4.77MPa$ each, and these were relatively low(F=18.4, P<.001), and as the post-test the Scheffe test was conducted and verified (p<.05). After examining the scheffe test, it was showed significant differences as PB>PO, PB>PN(p<.001). Through this study, in order to enhance the bonding force between PEKK and the composite resin, perform the Air abrasion and surface treatment by using Single Bond Universal(3M ESPE) is recommended, and as coMPared with other studies. And it is assumed that the increase of the application time of the Air abrasion affects the increase of the shear bond strength. Thus, further research is required.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.1082-1090
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• 2009

Peak expiratory flow rate(PEF) is a very important diagnostic parameter obtained from the forced vital capacity(FVC) test. The expiratory flow rate increases during the short initial time period and may cause measurement error in PEF particularly due to non-ideal dynamic characteristic of the transducer. The present study evaluated the initial rise slope($S_r$) on the flow rate signal to compensate the transducer output data. The 26 standard signals recommended by the American Thoracic Society(ATS) were generated and flown through the velocity-type respiratory air flow transducer with simultaneously acquiring the transducer output signal. Most PEF and the corresponding output($N_{PEF}$) were well fitted into a quadratic equation with a high enough correlation coefficient of 0.9997. But only two(ATS#2 and 26) signals resulted significant deviation of $N_{PEF}$ with relative errors>10%. The relationship between the relative error in $N_{PEF}$ and $S_r$ was found to be linear, based on which $N_{PEF}$ data were compensated. As a result, the 99% confidence interval of PEF error was turned out to be approximately 2.5%, which was less than a quarter of the upper limit of 10% recommended by ATS. Therefore, the present compensation technique was proved to be very accurate, complying the international standards of ATS, which would be useful to calibrate respiratory air flow transducers.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.669-675
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• 2007

The present study was conducted to explore the anti-inflammatory action of $2-hydroxyethyl-{\beta}-undecenate$ (HPS) purified from Cumin (Cuminum cymium L.) seed against periodontitis. From the study in which human leukocyte was employed to detect the inhibiting effects of 5-lipokygenase and cyclooxygenase, enzymes generating carriers of infection like $LTB_4$ and PGs, as well as of collagenase and elastase, organ-destroying enzymes, following conclusions could be drawn: HPS was found to inhibit leukotrien $B_4$ biosynthesis by stimulating more than 97% of human polymorphonuclear leukocyte (PMNL) with addition of $5\;{\times}\;10^{-2}\;M$ when $IC_{50}$ was set at $2\;{\times}\;10^{-4}\;M$. Ninety-two percent of enzyme activation turned out to be inhibited when $5\;{\times}\;10^{-2}\;M$ was added in a test to prove inhibiting effects of HPS against activation of PMNL 5-lipoxygenase from homogeneous humans and purified 5-lipoxygenase on the market. Besides, $IC_{50}$ for enzyme activation was valued at $2.5\;{\times}\;10^{-4}\;M$, while the value of $IC_{50}$ for purified 5-lipoxygenase was $2.3\;{\times}\;10^{-4}\;M$. The $IC_{50}$ values of COX-activated leukocyte and purified collagenase were $5.1\;{\times}\;10^{-4}\;M$ and $2.3\;{\times}\;10^{-4}\;M$, respectively. Moreover, the value of $IC_{50}$ for activation of leukocyte collagenase was $2\;{\times}\;10^{-3}\;M$, whereas that for purified collagenase was $5\;{\times}\;10^{-2}\;M$. In case of leukocyte elastase, addition of $5\;{\times}\;10^{-2}\;M$ inhibited its activation by 66%. In case of purified one, however, activation of enzyme was inhibited by 25% with addition of $5\;{\times}\;10^{-2}\;M$. Furthermore, the $IC_{50}$ value for activation of leukocyte elastase was revealed to be $7.5\;{\times}\;10^{-3}\;M$. From the virulence test with human gingiva cell, it was shown that, on the second day of cultivation, 47.83% of the cell had been activated when HPS was added by $5\;{\times}\;10^{-2}\;M$. Even the addition of HPS by $1\;{\times}\;10^{-2}\;M$ featured 68.53% of cell activation, suggesting relatively strong toxicity of the substance against gingiva cell.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.257-269
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• 2021

This study aimed to secure basic data for the development and operation of well-aging education programs by analyzing the physical, mental, and socio-economic needs of well-aging education for successful aging. The research tool was developed as a questionnaire to investigate the perception of well aging and the needs of well-aging education in terms of physical, mental, and socio-economic aspects. In February 2021, 1949 adults over the age of 19 were surveyed through an online and mobile survey by Gallup Korea. Descriptive statistics analysis, variance analysis, Borich needs analysis, and IPA analysis were conducted to analyze the needs of well-aging education. The results revealed economic power, exercise, and chronic disease management to be high in terms of the overall priority of the education needs for well-aging, and infectious disease management, independence, and social responsibility were surveyed in the order of low education needs. In terms of economic power, education needs were highest among all age groups except for the middle-age group (35-49 years old), 82.4% of all respondents, and education needs for exercise and chronic disease management were highest in the middle-age group. Therefore, it is necessary to develop well-aging education programs for each life cycle. These results are expected to be used as empirical data in establishing a platform for developing and operating educational programs for well aging.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.3
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• pp.365-369
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• 2008

This study analyzed the incidence of wound infection after the operation of mandibular third molar extraction in relation with antibiotic prophylaxis with the object of young and healthy patients. The study object was 1,177 mandibular third molars of 850 men of 20 to 25 years old without any specific systemic disease. Three methods of preventive antibiotic medication were selected according to the preventive antibiotic medication previously reported; three experimental groups were selected based on them, and the antibiotic used was amoxicillin($^{(R)}Kymoxin$, Yuhanyanghaeng, Seoul). The group 1 includes the patients that took the antibiotic orally before the operation(one hour earlier, 500mg) and for three days after the operation(250mg per time, three times/day), the group 2 is the ones that took the same antibiotic orally only once about one hour before the operation(500mg), and the group 3 did not take any antibiotics before and after the operation. And to compare the difficulties and the degrees of extraction during operations which can be possibly related to the wound infection after the operations, the mandibular third molars' impacted depths and extraction methods were investigated as well. To check if the wound was infected, observations with an internal of one week were performed twice after the operation, and the meaningfulness of the infection incidence was verified through Chi-square test using SPSS program(SPSS Inc., IL, USA). There was no statistically significant difference between the antibiotic medication methods and the wound infection incidence after the operation among the experimental groups. As examining the relations between the mandibular third molar operation methods and the wound infection incidence after the operation, there existed a statistically meaningful difference in the infection incidence according to the operation methods(p=0.020). And there was no statistically significant difference in the wound infection incidence according to the impacted depth of the mandibular third molar. Therefore, it is thought that there exists little necessity of prophylatic antibiotics medication when extracting the mandibular third molar of young and healthy men without any systemic disease in general; however, in case when it is expected that the possibility of infection will be high or the wound on the tissue will be severe, it is sure that the prophylactic antibiotics medication will be necessary.

• Applied Microscopy
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• v.39 no.4
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• pp.325-332
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• 2009

It has been well known that grapefruit seed extract (GSE) have effects on the deodorization and a wide range disinfectant. But anybody do not research about the decomposition-inhibition effect of GSE. The present study was performed to investigate the decomposition-inhibition effect of GSE by measuring the microscope and electroscope observation with passage of time. A total of 30 healthy Sprague-Dawley (SD) rats weighting from 230 gm to 250 gm were used as experimental animals. One group that do not treated by GSE named control group and the other group that treated by 55% GSE named Experimental group. Under ether anesthesia, right kidney was obtained. Put each sample in $37^{\circ}C$ and humidity $80{\pm}5%$ incubator, we obtained each sample after 0 day, 1 day, 2 days, 3 days, 4 days and 5 days. 4 ${\mu}m$ of paraffin sections were obtained, stained H-E stain and observed by use of a microscope. Morphological change in tissue was similar to control 1 day group and experimental 3 days group. Therefore, decomposition-inhibition effect of GSE continued about 2 days and it protected necrosis. According to above results, the author suggest that 55% GSE is an effective decomposition inhibitor until 2 days on $37^{\circ}C$ and humidity $80{\pm}5%$ conditions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5196-5205
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• 2012

Purpose: The Purpose of this study were to compare the level of perception and to identify factors associated with perception on patient safety culture by nurses and hygienists. Method: The data were collected from september to December, 2010 using Hospital survey on patient safety culture questionnaires. The subjects were 399 Nurses, hygienists, recruited from the hospital in Busan & Kyungnam. The collected data were analyzed using SPSS descriptive statistics, mean and standard deviation, t-test and ANOVA, Spearman rank coefficient. Result: The perception level of nurses on patient safety culture was 3.48. In case of hygienists, the level was 3.51. Compared to nurses, hygienists showed a significantly difference on the items "Staff arrangement"(t=2.841, p<.01) and "Administator attitude"(t=-2.471, p<.05), "Feedback and communication in accident"(t=-3.356, p<.01). Nurses and hygienists' age and career, working hour per week were identified as factor associated with patient safety culture. Conclusion: The perception level of hospital health providers on patient safety culture was moderate. and identified factors associated with patient safety culture were age and career, working hour per week.

• Journal of the Korea Society of Computer and Information
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• v.25 no.1
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• pp.117-124
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• 2020

In this paper, we proposed a plan to maintain comfortable indoor air quality in nursing homes by suggesting ways to reduce items temporarily exceeding the reference values through real-time concentration variation analysis of indoor air quality. Five items including PM10, CO₂, CO, VOC, and Radon are measured at nursing homes in spring (April) and autumn (September) was carried out and all of the measured items were analyzed to satisfy the criteria set by the Indoor Air Quality Control Act. As a result of the analysis of the real-time concentration change, the concentration of CO₂ was close to the reference value based on the number of occupants in the sick room. Due to the disinfectant (alcohol) used to disinfect and the auxiliary tools (adhesive) used in the operation of the program such as making and coloring, it was analyzed to temporarily exceed the standard value in the hall. In conclusion, it is possible to provide pleasant indoor air quality and contribute to securing the nursing home's competitiveness if periodic ventilation, natural disinfectant and eco-friendly product are used in consideration of the thermal environment.

• Journal of the Korea Convergence Society
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• v.8 no.12
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• pp.129-137
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• 2017

The purpose of the study is to investigate the convergence influence of excessive smartphone use on attention deficit, learning environment, and academic procrastination in health college students. A self-reported questionnaire was completed by 255 college students in Busan drom March 6 to June 12, 2017. The degree of smartphone overuse, lack of attention, learning environment, and academic procrastination according to smartphone use characteristics showed significant effects on the time spent on smartphones per day, awareness of smartphone addiction, and personal use of smartphones during class time (p<0.001). It was shown that smartphone overuse was positively correlated with attention deficit (r=0.870, p<0.01), learning environment (r=0.812, p<0.01), academic procrastination (r=0.772, p<0.01), and attention deficit showed a positive relationship with learning environment (r=0.918, p<0.01) and academic procrastination (r=0.798, p<0.01) Learning environment was positively correlated with academic procrastination (r=0.777, p<0.01). The influence factors of smartphone overuse were attention deficit (p<0.001), followed by academic delay behavior (p<0.01). It is necessary to establish a healthy learning environment through prevention and proper use of smartphone.

• Journal of the Korea Convergence Society
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• v.7 no.4
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• pp.107-121
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• 2016

This study aimed to seek the way of effectively managing job stress of shift work nurses, to improve nursing performance, the influence of job stress of shift work nurses on nursing performance through convergence research. A total of 244 questionnaires obtained by a survey targeting nurses, who were doing shift work in a university hospital located in B city, in the period from March 2 to 15, 2015 were analyzed using the SPSS 21.0 program. As a result, the mean score of job stress was 3.57 points, and the mean score of nursing performance was 3.69 points. Job stress made a significant positive(+) influence on the sub-dimensions of interpersonal duty. Therefore, efforts should be made to more accurately identify shift work nurses' job stress and efficiently manage the nursing personnel. Moreover, if shift work nurses' job stress is effectively managed by preparing practical job stress management intervention programs for continuous improvement of nursing performance, high quality medical services will be provided through high quality nursing practice.