• Journal of Korean society of Dental Hygiene
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• v.14 no.3
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• pp.391-398
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• 2014

Objectives : The purpose of the study is to investigate the oral health knowledge and behavior in teachers with or without the school dental clinic. Methods : The subjects were 133 teachers with or without the school dental clinic in Gunsan. A self-reported questionnaire was filled out by the teachers from September 9 to November 2, 2013. The data were analyzed by SPSS version 21.0. Results : The groups were divided into two. Experimental group was school dental clinic operation group and the control group was no operation group. The experiment group showed the high score of recognition of fluoridation and sealant(p<0.01). The control group showed the high score of recognition of sealant(p<0.01). Conclusions : Continuous operation of the school dental clinic is essential to promote the lifelong oral health care in the elementary school children and the teachers. So the nationwide expansion of the continuous school dental clinic is very important to prevent the dental caries in the elementary school children.

• Culinary science and hospitality research
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• v.9 no.2
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• pp.64-84
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• 2003

There is this research that supply better experience and satisfaction of most suitable in users standpoint to users through family restaurant website importance and assessment of satisfaction. Also, there is purpose of this research to supply pendulum in family restaurant internet marketing strategy establishment that website can achieve continuous role as marketing means to be not public information that drive revisit and substantial restaurant visit. Family restaurant website estimation received satisfaction assessment which do not get in importance (expected value) in general as analysis result. In other words, domestic family restaurants website are doing construction. operation by marketing means but real users are various interaction part that can collect and achieve about customer opinion except design part that can do to emboss company's image could see side that satisfaction is unenchanted and presented improvement way in website construction. operation on contents part of various and correct information offer and so on that customer infancy strategy part and user of event and coupon event etc. that is distinction robbers need. Also, realization possibility for restaurant prescription that latent customers who use net can raise family restaurant website revisit and substantial sale could see side. Ditto improvement way in that family restaurants construct and operate website conclusively as a marketing tool that public information is not that three offers satisfaction of most suitable to latent customers who use existent net to website as can achieve continuous role contribute.

• Journal of Environmental Science International
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• v.25 no.3
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• pp.385-393
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• 2016

Oxidative and thermal degradation of alkanolamines for a promising $CO_2$ capture technology of absorption might cause decrease in $CO_2$ capture efficiency and formation of hazardous byproducts. In this study, characteristics of a representative absorbent of monoehtanolamine (MEA) were examined for a long term operation using a laboratory scale absorption system. An $CO_2$ absorption system with ID 56 mm and absorption zone height 100 cm was developed for the characterization. Absorption solution of 30 wt% MEA was circulated at 100 mL/min to treat air with 15% $CO_2$ and 1 ppm NO at 10 L/min. Temperatures of absorber and stripper were maintained at $40^{\circ}C$ and $120^{\circ}C$, respectively. For the course of 5 weeks continuous operation, MEA concentration was decreased approximately by 70% and $CO_2$ removal efficiency was dropped from 95% to 65%. Ionic byproducts of $NH_4{^+}$, $NO_2{^-}$, and $NO_3{^-}$ were accumulated up to 48 g/mL, 0.2 g/mL, and 1.5 g/mL, respectively, tracking the variation of MEA concentration. Formation of various organic byproducts were also observed.

• Solar Energy
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• v.11 no.2
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• pp.29-33
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• 1991

The present paper deals with two types of heating methods widely used for the Radiant Floor heating systems in Korea. Of these, one method circulates hot water according to the predefined schedule ("intermittent heating") while the other runs the system with the aid of thermostats ("continuous heating"). The standard version of SERI-RES has been modified for the numerical simulation of the problem. Preliminary results show relatively large temperature swings in the case of intermittent heating with solar availability. On the other hand, the case of continuous heating would avoid such undesirable temperature fluctuations. These results are also verified by experimental evaluations.

• Korean Journal of Veterinary Research
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• v.45 no.3
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• pp.405-410
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• 2005

To analyze and identify selected risk factors for infectious bronchitis virus (IBV) infection in the growing and laying period of laying-hen flocks, a longitudinal field study was conducted with 27 commercial flocks reared in three provinces of Korea during the period from May 2003 to April 2004. Using monitored data for IBV infection status among study flocks we computed the multivariate odds ratios (ORs) and their corresponding confidence intervals (CIs), and population attributable risks (PARs). Multivariate logistic regression showed significant risk increments for: continuous entry of chick (OR=1.9, 95% CI, 0.7-69.1) and operation years of the layer house greater than or equal to 5 years (OR=3.2, 95%CI, 1.6-389.9). No significant interaction was found between variables. The PAR suggested that continuous entry of chick (PAR=32%) and ${\geq}5years$ of house operation (PAR=84%) had the highest impacts on IB presence in laying-hen flocks under study. Of the two significant factors, however, operation year of the layer house lacks an easy applicability in preventing IB control strategies, and the possibility of confounder cannot be ruled out.

• Journal of Power Electronics
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• v.18 no.1
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• pp.11-22
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• 2018

This paper presents a single switch, high step-up, non-isolated dc-dc converter suitable for renewable energy applications. The proposed converter is composed of a coupled inductor, a passive clamp circuit, a switched capacitor and voltage lift circuits. The passive clamp recovers the leakage inductance energy of the coupled inductor and limits the voltage spike on the switch. The configuration of the passive clamp and switched capacitor circuit increases the voltage gain. A wide continuous conduction mode (CCM) operation range, a low turn ratio for the coupled inductor, low voltage stress on the switch, switch turn on under almost zero current switching (ZCS), low voltage stress on the diodes, leakage inductance energy recovery, high efficiency and a high voltage gain without a large duty cycle are the benefits of this converter. The steady state operation of the converter in the continuous conduction mode (CCM) and discontinuous conduction mode (DCM) is discussed and analyzed. A 200W prototype converter with a 28V input and a 380V output voltage is implemented and tested to verify the theoretical analysis.

• Journal of Korean Neurosurgical Society
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• v.39 no.4
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• pp.265-270
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• 2006

Objective : Microvascular decompression[MVD] at root exit zone[REZ] of the facial nerve has been largely popularized and it has become the standard treatment for patients with hemifacial spasm[HFS]. This sturdy is performed to evaluate the efficacy of MVD over the course of time. Methods : From 1994 to 2003, 50 patients with HFS who underwent MVD were followed up for more than 6 months. We retrospectively analyzed results with medical records and telephone researches. Results : The mean age of patients at the time operation was 57.6 years and 84% of the patients were female. The mean duration of follow-up after operation was 3.4 years [range $0.5{\sim}7.8\;years$]. One day after MVD, 54% of patients had complete relief of spasm immediately. Continuous improvements of HFS were observed during the follow-up period and these improvements were statistically significant with time (P< 0.05). Until 6 months after operation, complete relief of spasm was observed in 84% of patients. The delayed relief of spasm was observed in 35.7% of our patients who experienced complete relief. Conclusion : The efficacy of MVD in HFS is improves with time. Continuous follow-up evaluations for the duration of more than at least 6 months after MVD are important for the decision of its clinical results because delayed relief of spasms occurs.

• Korean Management Science Review
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• v.10 no.2
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• pp.111-120
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• 1993

The most important factors for a product to survive in the market are cost and quality. In recent years, quality proceeds to cost. There are many techniques of use to improve the quality of a product. One of the techniques is applying statistical methods (especially Taguchi method) to real operational conditions for a continuous manufacturing process in P company. There are 91 factors to control in the process. So, we predetermined 7 main effect factors and 6 interactive effect factors by statistical methods and advices of engineers. With these 13 factors, we determined the optimal level of operations for the process.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.61.6-61
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• 2002

In these days, Block Pulse functions are used in a variety of fields such as the analysis and controller design of the systems. In applying the Block Pulse function technique to control and systems science, the integral operation of the Block Pulse series plays important roles. This is because differential equations are always involved in the representations of continuous-time models of dynamic systems, and differential operations are always approximated by the corresponding Block Pulse series through integration operational matrices. In order to apply the Block Pulse function technique to the problems of continuous-time dynamic systems more efficiently, it is necessary to find th...

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.357-360
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• 1999

A 20 MHz CMOS continuous low-pass filter using simulated floating inductor consisted of two fully-differential transconductors and a capacitor is presented. The theory of operation is described and simulation results show close agreement between predicted behaviour and experimential performance. Simulation results show that the filter has ripple bandwidth of 22 MHz, pass-band ripple of 0.36 ㏈. and cutoff frequency of 26 MHz at supplay voltage of $\pm$3 V. The power dissipation is 19.2 ㎽.