• Journal of the korean academy of Pediatric Dentistry
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• v.41 no.2
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• pp.134-144
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• 2014

The aim of this study was to investigate changes in treatment patterns within pediatric dentistry departments by analyzing the distribution of patients and treatment trends. To that end, treatment charts based on electronic medical records (EMR) from the Yonsei University Dental Hospital from 2008 to 2012 were collected and analyzed. The results showed a decrease in the number of new patients and patients cared for by non-specialists, while the number of foreign patients has increased. The under 2 years-old group accounted for a large portion of new patients. Dental caries, dental trauma, and malocclusion ranked as the top complaints. In terms of restoration treatment, the proportion of patients receiving composite resin, amalgam, and sealant has decreased, whereas self-curing glass ionomer and preventive resin restoration have increased. Single-visit endodontic treatment has been increasing, with a decreasing trend in multi-visit endodontic treatment. The rate of conservative pulp treatment, such as pulp capping and pulpotomy, has increased. For reducing patient anxiety, treatments under sedation have increased, especially with the use of nitric oxide. This investigation into the latest treatment trends and patient characteristics is expected to help pediatric dentists to make appropriate treatment plans.

• Journal of Chest Surgery
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• v.32 no.5
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• pp.438-441
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• 1999

Background: Minimally invasive cardiac surgery has emerged as a new approach to the conventional median sternotomy. The suggested advantages of the minimally invasive technique includes improved cosmesis, simplicity of opening and closing the chest, less postoperative pain, less risk of infection and bleeding, early rehabilitation, and reduced length of hospital stay. Material and Method: Between March 1997 and December 1997, we performed 36 cases of minimally invasive cardiac surgery via three different approaches ; right paramedian, transverse sternotomy and mini-sternotomy with upper sternal split. Result: There was no operative mortality. Postoperative complications were atrial fibrillation in 4 patients, bleeding that required reoperation in 1 patient, and delayed wound closure in 1 patient who underwent 3rd redo operation. Average length of skin incision was 9.1${\pm}$0.9 cm. Average duration of stay in the intensive care unit was 48${\pm}$29 hours and the patients were discharged 10${\pm}$7 days after the operation. Conclusion: In spite of the difficulties in defibrillation, deairing, and cardiac decompensation, minimally invasive approaches will be applied increasingly because of the suggested advantages.

• The Journal of Society for e-Business Studies
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• v.16 no.3
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• pp.1-22
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• 2011

The purpose of this study is to verify the relationship between expectancy confirmation and continuance usage intention in biometric technology. We extend the continuance usage intention model, TAM and expectation confirmation theory by adding perceived privacy, perceived security and trust. Results was analyzed by using structural equations model. The results show that satisfaction and perceived usefulness have positive effect on continuance usage intention in the bright scenario. Perceived privacy and perceived security are positive factors on perceived usefulness, and perceived privacy is positive effect on perceived security. On the other hand, the respondents who are exposed to the dark scenario have negative effects on the perceived privacy, perceived security and trust. And finally, trust has no significant effect on the perceived usefulness.

• Journal of Korean Society of Transportation
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• v.19 no.2
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• pp.89-98
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• 2001

The objective of this Paper is to derive an adjustment factor for the presence of heavy vehicles when estimating capacity at unsignalized intersections (and/or at modern roundabouts). According to the 1997 and 2000 Highway Capacity Manual (HCM), potential capacity in such cases is estimated by simply adjusting base critical gap and base follow-up time. However, the procedure suggested in the HCM may lead to some errors in the adjustment, hence resulting in poor evaluation and design for the intersections, because it determines the value of adjusting factors by only the number of lanes on main streets regardless of the types of heavy vehicles. This paper shows a simple formula for making the adjustment. This formula is much like the HCM formula used for heavy vehicles in estimating highway capacity by the adoption of passenger car units (PCU). In contrast to the traditional approaches seen in the HCM, the PCU value of this case is explicitly expressed by the flow rate in the major streams and the gap difference in critical gaps chosen by passenger cars and particular heavy vehicles. Computational results of the adjustment factor are graphically illustrated.

• Korean Journal of Environmental Biology
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• v.20 no.2
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• pp.180-188
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• 2002

Sand dollar, Astriclypeus manni (Echinodermata: Echinoidea) is widely distributed on subtidal sand flats all along the coast of Cheju Island. Limited information has been reported on their ecology despite their abundance. This study reports gut contents, density and locomotion of the sand dollars distributed on a subtidal sand flat on the north-east coast of Cheju Island. Microscopic examination of the gut contents indicated that A. manni feeds on inorganic and organic detritus as well as live organisms contained in the sediments. Inorganic particles included sand grains, sponge spicules and shells of benthic animals such as foraminifera, crustacean and molluscs. Mean diameter of sediment particles retained in the gut was $77.6\pm{22.2}\mu{m}$. Live organisms retained in the gut included foraminifera, harpacticoid copepods, nematodes, diatoms and unidentified egg. Spatial distribution pattern of the sand dollar was found to be random with a mean density of 0.4 individual $m^{-2}(\chi^2=85.16,\;p>0.05)$. Locomotion speed of the sand dollar measured in situ was 2.0 to 65.0 cm $hr^{-1}$. Locomotion speed and moving distance was somewhat higher in summer when food availability also higher.

• The Journal of the Korea Contents Association
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• v.16 no.10
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• pp.96-107
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• 2016

This study examined the relationship between leisure needs and perception of psycho-social aging among 1307 older adults aged over 60 years utilizing social services of a social welfare center for senior citizens in Seoul, Korea. A convenience sample of this study was collected for three weeks in December 2012 among older adults via paper survey. Hierarchical multiple regression was utilized to analyze collected data. The present study demonstrated that age, years of education, perception of health status, and perception of economic status were significantly associated with perception of successful aging. However, years of education and perception of economic status were no longer significantly associated with perception of psycho-social aging, when leisure needs was included. Age, perception of health status, and hobbies/entertainment activities and employment/plan of later years activities among types of leisure needs were significantly associated with perception of psycho-social aging. This finding demonstrates that leisure needs influence perception of psycho-social aging. Implications and suggestions to improve perception of psycho-social aging among older adults are discussed.

• Journal of Korea Water Resources Association
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• v.39 no.7 s.168
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• pp.593-603
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• 2006

The basin response to storm is regarded as nonlinearity inherently. In addition, the consistent nonlinearity of hydrologic system response to rainfall has been very tough and cumbersome to be treated analytically. The thing is that such nonlinear models have been avoided because of computational difficulties in identifying the model parameters from recorded data. The parameters of nonlinear system considered as dynamic effects in the conceptual model are optimized as the sum of errors between the observed and computed runoff is minimized. For obtaining the optimal parameters of functions, the historical data for the Bocheong watershed in the Geum river basin were tested by applying the numerical methods, such as quasi-linearization technique, Runge-Kutta procedure, and pattern-search method. The estimated runoff carried through from the storage function with dynamic effects was compared with the one of 1st-order differential equation model expressing just nonlinearity, and also done with Nash model. It was found that the 2nd-order model yields a better prediction of the hydrograph from each storm than the 1st-order model. However, the 2nd-order model was shown to be equivalent to Nash model when it comes to results. As a result, the parameters of nonlinear 2nd-order differential equation model performed from the present study provided not only a considerable physical meaning but also a applicability to Korean watersheds.

• The Journal of the Petrological Society of Korea
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• v.23 no.2
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• pp.153-162
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• 2014

The social demands to conserve the geological outcrops with important scientific values are increasing. Accordingly public programs such as national geopark are recently established. In this study, outcrops with geological values in the Dusong Peninsula geosite of the Busan National Geopark are investigated in details with a discussion in the aspects of geoheritage values. The Dusong Peninsula is located in the late Cretaceous Dadaepo Basin interpreted as an intra-arc pull-apart basin extended in the Cretaceous Yucheon Subbasin. In this area, a number of noticeable geological records, such as andesitic sills, lower Dadaepo Formation, paleo-seismites, clastic dikes, compound calcrete deposits, syn-depositional normal faults, and unconformity between basin-fill and basements, are observed. Considering their unique geological significance, the strategic plans for their conservation and management should be urgently provided.

• The Journal of the Petrological Society of Korea
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• v.23 no.2
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• pp.31-43
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• 2014

The Yeongdeok granite emplaced in the eastern Yeongyang subbasin is typically a medium- to coarse-grained massive biotite granite. It intruded into Precambrian schist & gneiss complex and is unconformably overlain by Cretaceous sedimentary rocks. In this study, we attempt to investigate the magma type which formed Yeongdeok granite and estimate the emplacement depth using Al-in-hornblende geobarometer to mineral composition. According to the magma fractionation, $TiO_2$, $Al_2O_3$, $Fe_2O_3{^*}$, FeO, $Fe_2O_3$, MnO, MgO, CaO, $Na_2O$ and $P_2O_5$ show positive trend but $K_2O$ indicate negative trend with $SiO_2$ contents. Those are identified as calc-alkaline series in AFM diagram and show the chemical characteristics of the I-type magma through the oxidation tendency of the iron ion and the portion of the alkaline composition. When calculated using the equation of Hollister et al. (1987), the emplacement depths of the Yeongdeok granite range from 8.98 to 17.19 km and average depth was estimated 13.03 km approximately.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.3
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• pp.284-291
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• 2016

In order to provide a diagnostic basis for predicting the possibility of the self-correction of ectopic first permanent molars, differences among normal eruption, reversible and irreversible ectopic eruption of maxillary first permanent molars were retrospectively analyzed. The angles of the long axes and the occlusal lines between the maxillary first permanent molar and the adjacent tooth were measured by panoramic radiographs. The occlusal relationship of second primary molars was also investigated. There is a statistically significant difference between the ectopic eruption group and normal group (p < 0.05), but not between the reversible and irreversible ectopic eruption groups (p > 0.05). The angles between the second primary molar and the first permanent molar, the second primary molar and the second permanent molar in ectopic groups showed a smaller degree than those of the control group. Mesial step was found more frequently in the ectopic eruption group than the normal group. In conclusion, the angulation of the first permanent molar and tooth germ of the maxillary second permanent molar showed close relation with ectopic eruption of the maxillary first permanent molar and ectopic first permanent molar is likely to occur in class III patients with maxillary deficiency.