• The Journal of Korean Academy of Prosthodontics
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• v.46 no.2
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• pp.148-156
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• 2008

Statement of problems: Self-etch adhesives exhibit some clinical benefits such as ease of manipulation and reduced technique-sensitivity. Nevertheless, some concern remains regarding the bonding effectiveness of self-etch adhesives to enamel, in particular when so-called 'mild' self-etch adhesives are employed. This study compared the microtensile bond strengths to ground enamel of the two-step self-etch adhesive Clearfil SE Bond (Kuraray) to the three-step etch-and- rinse adhesive Scotchbond Multi-Purpose (3M ESPE) and the one-step self-etch adhesive iBond (Heraeus Kulzer). Purpose: The purpose of this study was to determine the effect of a preceding phosphoric acid conditioning step on the bonding effectiveness of a two-step self-etch adhesive to ground enamel. Material and methods: The two-step self-etch adhesive Clearfil SE Bond non-etch group, Clearfil SE Bond etch group with prior 35% phosphoric acid etching, and the one-step self-etch adhesive iBond group were used as experimental groups. The three-step etch-and-rinse adhesive Scotchbond Multi-Purpose was used as a control group. The facial surfaces of bovine incisors were divided in four equal parts cruciformly, and randomly distributed into each group. The facial surface of each incisor was ground with 800-grit silicon carbide paper. Each adhesive group was applied according to the manufacturer's instructions to ground enamel, after which the surface was built up using Light-Core (Bisco). After storage in distilled water at $37^{\circ}C$ for 1 week, the restored teeth were sectioned into enamel beams approximately 0.8*0.8mm in cross section using a low speed precision diamond saw (TOPMET Metsaw-LS). After storage in distilled water at $37^{\circ}C$ for 1 month, 3 months, microtensile bond strength evaluations were performed using microspecimens. The microtensile bond strength (MPa) was derived by dividing the imposed force (N) at time of fracture by the bond area ($mm^2$). The mode of failure at the interface was determined with a microscope (Microscope-B nocular, Nikon). The data of microtensile bond strength were statistically analyzed using a one-way ANOVA, followed by Least Significant Difference Post Hoc Test at a significance level of 5%. Results: The mean microtensile bond strength after 1 month of storage showed no statistically significant difference between all adhesive groups (P>0.05). After 3 months of storage, adhesion to ground enamel of iBond was not significantly different from Clearfil SE Bond etch (P>>0.05), while Clearfil SE Bond non-etch and Scotchbond Multi-Purpose demonstrated significantly lower bond strengths (P<0.05), with no significant differences between the two adhesives. Conclusion: In this study the microtensile bond strength to ground enamel of two-step self-etch adhesive Clearfil SE Bond was not significantly different from three-step etch-and-rinse adhesive Scotchbond Multi-Purpose, and prior etching with 35% phosphoric acid significantly increased the bonding effectiveness of Clearfil SE Bond to enamel at 3 months.

• Journal of Intelligence and Information Systems
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• v.18 no.2
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• pp.143-156
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• 2012

People easily believe that news and stock index are closely related. They think that securing news before anyone else can help them forecast the stock prices and enjoy great profit, or perhaps capture the investment opportunity. However, it is no easy feat to determine to what extent the two are related, come up with the investment decision based on news, or find out such investment information is valid. If the significance of news and its impact on the stock market are analyzed, it will be possible to extract the information that can assist the investment decisions. The reality however is that the world is inundated with a massive wave of news in real time. And news is not patterned text. This study suggests the stock-index invest model based on "News Big Data" opinion mining that systematically collects, categorizes and analyzes the news and creates investment information. To verify the validity of the model, the relationship between the result of news opinion mining and stock-index was empirically analyzed by using statistics. Steps in the mining that converts news into information for investment decision making, are as follows. First, it is indexing information of news after getting a supply of news from news provider that collects news on real-time basis. Not only contents of news but also various information such as media, time, and news type and so on are collected and classified, and then are reworked as variable from which investment decision making can be inferred. Next step is to derive word that can judge polarity by separating text of news contents into morpheme, and to tag positive/negative polarity of each word by comparing this with sentimental dictionary. Third, positive/negative polarity of news is judged by using indexed classification information and scoring rule, and then final investment decision making information is derived according to daily scoring criteria. For this study, KOSPI index and its fluctuation range has been collected for 63 days that stock market was open during 3 months from July 2011 to September in Korea Exchange, and news data was collected by parsing 766 articles of economic news media M company on web page among article carried on stock information>news>main news of portal site Naver.com. In change of the price index of stocks during 3 months, it rose on 33 days and fell on 30 days, and news contents included 197 news articles before opening of stock market, 385 news articles during the session, 184 news articles after closing of market. Results of mining of collected news contents and of comparison with stock price showed that positive/negative opinion of news contents had significant relation with stock price, and change of the price index of stocks could be better explained in case of applying news opinion by deriving in positive/negative ratio instead of judging between simplified positive and negative opinion. And in order to check whether news had an effect on fluctuation of stock price, or at least went ahead of fluctuation of stock price, in the results that change of stock price was compared only with news happening before opening of stock market, it was verified to be statistically significant as well. In addition, because news contained various type and information such as social, economic, and overseas news, and corporate earnings, the present condition of type of industry, market outlook, the present condition of market and so on, it was expected that influence on stock market or significance of the relation would be different according to the type of news, and therefore each type of news was compared with fluctuation of stock price, and the results showed that market condition, outlook, and overseas news was the most useful to explain fluctuation of news. On the contrary, news about individual company was not statistically significant, but opinion mining value showed tendency opposite to stock price, and the reason can be thought to be the appearance of promotional and planned news for preventing stock price from falling. Finally, multiple regression analysis and logistic regression analysis was carried out in order to derive function of investment decision making on the basis of relation between positive/negative opinion of news and stock price, and the results showed that regression equation using variable of market conditions, outlook, and overseas news before opening of stock market was statistically significant, and classification accuracy of logistic regression accuracy results was shown to be 70.0% in rise of stock price, 78.8% in fall of stock price, and 74.6% on average. This study first analyzed relation between news and stock price through analyzing and quantifying sensitivity of atypical news contents by using opinion mining among big data analysis techniques, and furthermore, proposed and verified smart investment decision making model that could systematically carry out opinion mining and derive and support investment information. This shows that news can be used as variable to predict the price index of stocks for investment, and it is expected the model can be used as real investment support system if it is implemented as system and verified in the future.

• Clinical and Experimental Pediatrics
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• v.50 no.6
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• pp.531-535
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• 2007

Purpose : Indomethacin treatment is successful in about 90% of patent ductus arteriosus (PDA) in premature infants, but in some, repeated administration or surgical closure is required. The object of the present study is to determine the factors affecting the efficacy of indomethacin treatment and to predict the treatment result. Method : The 29 preterm neonates, admitted to neonatal intensive care unit of Kyunghee university medical center and Eulji university hospital between September 2002 and April 2006 were diagnosed of PDA and treated with indomethacin. The risk factors that might affect the efficacy of treatment were studied retrospectively. Results : The single-administered group was 19 patients out of 29 (65.5%) and among the repeated-administered group, 5 patients (17.2%) had repeated indomethacin administration and the other 5 patients (17.2%) underwent surgery due to reopening of the duct after repeated medical treatment. In repeated-administered group, the diameter of PDA was significantly larger ($3.66{\pm}0.8mm$ vs $2.55{\pm}0.8mm$, P<0.01), especially when larger than 3.5 mm (sensitivity: 70%, specificity: 89%). Also, the mean postnatal age of the first indomethacin administration was significantly delayed in repeated-administered group (19.7 days vs 12.5 days, P<0.05). There were no significant differences in gestational age (32 wk 5 days vs 30 wk 8 days) and in birth weight (1598.9 g vs 1750.5 g). There were no significant differences in associated morbidities. Conclusion : In patients with larger diameter of PDA (>3.5 mm) and older postnatal age (>7 days), the effect of indomethacin was decreased. Therefore in such cases, repeated dose of indomethacin or surgical ligation should be considered earlier.

• Clinical and Experimental Pediatrics
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• v.49 no.9
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• pp.946-951
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• 2006

Purpose : The purpose of this study was to demonstrate the effectiveness of combined exercise for 12 weeks on the adiponectin and obesity related variables in overweight and obese children. Methods : Eighteen children in 5th grade in a certain elementary school in Busan were recruited. They were all overweight or obese children(more than 85 percentile in body mass index). Nine children in the experimental group were given exercises consisting of walking and band resistant training for 12 weeks. Auxological data(including height, weight and body fat mass) and laboratory data (fasting blood sugar, insulin, adiponectin) were checked at baseline and at the 1 week, and at the 4 weeks and 12 weeks stages of their exercise program. Insulin resistance and sensitivity were evaluated indirectly using HOMA index and QUICKI index. Results : Adiponectin gradually decreased until the 4 weeks point and gradually increased thereafter to the starting level at the 12 weeks stage. Body weight, body mass index(BMI) and HOMA index significantly decreased more at the 1 week, 4 weeks, and 12 weeks stages in the experimental group than in the control group. Body fat mass significantly decreased at 12 weeks. The change of insulin was significantly correlated with changes of body weight and BMI. But there was no correlation between changes of adiponectin and changes of insulin. Conclusion : Exercise seems to effect the adiponectin concentration. And it might be assumed that exercise increases the adiponectin concentration if it is continued for long time(may be more than 12 weeks). More studies may be necessary to draw that conclusion.

• Clinical and Experimental Pediatrics
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• v.48 no.3
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• pp.284-291
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• 2005

Purpose : Flow cytometric automated reticulocyte analysis is a superior method to manual reticulocyte counting, with respect to precision and sensitivity. Furthermore, flow cytometric analysis is able to measure immature reticulocyte fraction(IRF) and reticulocyte cellular indices(RCI : cell hemoglobin content : CHr, mean cell volume : MCVr, cell hemoglobin concentration mean : CHCMr, distribytion width : RDWr, HDWr, CHDWr). In this study, we investigated the mean values and clinical significances of IRF and RCI in healthy children and pediatric anemia patients. Methods : IRF and RCI were measured with an automated blood cell analyzer, ADVIA 120(Bayer, USA) using oxazine 750 dye, in 57 healthy children and 61 children with anemia. The anemia group consisted of 27 iron deficiency anemia(IDA) patients and 34 patients with anemia associated with acute infection(AAI). We compared the mean values of IRF and RCI in the control group classified according to age, between anemia groups and the control group, and between the IDA group and the AAI group. Results : For the normal control group, the mean values of IRF, CHr, MCVr and HDWr were higher in neonates when compared to older children. The mean values of IRF and RDWr were significantly higher, and the mean values of CHr and CHCMr were significantly lower in the IDA group when compared to the control group. The mean value of IRF was significantly higher, and the mean value of CHDWr was significantly lower in the AAI group when compared to the control group. The mean values of IRF, CHr and CHCMr were significantly lower in the IDA group when compared to the AAI group. Conclusion : We could determine the normal mean values of IRF and RCI in healthy children classified according to age for understanding of hematopoietic response differences according to age. The evaluation of IRF and RCI by automated reticulocyte analyzer seemed to be accurate and clinically useful for the early diagnosis of anemia and the differentiation of IDA from AAI.

• Tuberculosis and Respiratory Diseases
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• v.56 no.6
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• pp.600-610
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• 2004

Background : The plasma B-type natriuretic peptide(BNP) concentration increases with the degree of pulmonary hypertension in patients with chronic respiratory disease. The aim of this study was to examine the prognostic role of BNP in the acute exacerbation of chronic obstructive lung disease (COPD). Method : We selected 67 patients who were admitted our hospital because of an acute exacerbation of COPD. Their BNP levels were checked on admission at the Emergency Department. Their medical records were analyzed retrospectively. The patients were divided into two groups according to their in-hospital mortality. The patients' medical history, comobidity, exacerbation type, blood gas analysis, pulmonary function, APACHE II severity score and plasma BNP level were compared. Results : Multiple logistic regression analysis identified three independent predictors of mortality: $FEV_1$, APACHE II score and plasma BNP level. The decedents group showed a lower $FEV_1$($28{\pm}7$ vs. $37{\pm}15%$, p=0.005), a higher APACHE II score($22.4{\pm}6.1$ vs. $15.8{\pm}4.7$, p=0.000) and a higher BNP level ($201{\pm}116$ vs. $77{\pm}80pg/mL$, p=0.000) than the sSurvivors group. When the BNP cut-off level was set to 88pg/mL using the receiver operating characteristic curve, the sensitivity was 90% and the specificity was 75% in differentiating between the survivors and decedents. On Fisher's exact test, the odds ratio for mortality was 21.2 (95% CI 2.49 to 180.4) in the patients with a BNP level > 88pg/mL. Conclusion : The plasma BNP level might be a predictor of mortality in an acute exacerbation of COPD as well as the $FEV_1$ and APACHE II score.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.2
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• pp.122-129
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• 2016

It is important to know the sensitivity of shrubs to de-icing salt in order to set guidelines for ecological tolerance of evergreen shrubs along roads. Therefore, the aim of this study was to investigate the influence of de-icing salt, calcium chloride($CaCl_2$), on the growth and physiological characteristics of three evergreen shrubs, Euonymus japonica, Rhododendron indicum, and Buxus koreana. Plants were exposed to calcium chloride at different concentrations(weight percentage, 0% as control, 1.0%, 3.0%, and 5.0%) through amended soil maintained from the start of the experiment in October of 2014 until termination in March of 2015. The survival rate, plant height, leaf length, leaf width, leaf shape index, number of leaves, fresh weight, dry weight, dry matter, root/top ratio, chlorophyll contents, fluorescence, photosynthesis, stomatal conduct, and transpiration rate were recorded. Elevated calcium chloride concentrations decreased plant height, leaf length, leaf width, leaf shape index, fresh weight, dry weight, dry matter, and R/T ratio of the three shrubs. Root growth responded more sensitively than the top growth to salinity. However Euonymus japonica was more tolerant to salt stress than Rhododendron indicum and Buxus koreana. Their growths were totally inhibited by $CaCl_2$ above 3.0% and 1.0% concentrations, respectively. Chlorophyll content, fluorescence, photosynthesis, stomatal conduct, and transpiration rate of both Rhododendron indicum and Buxus koreana were reduced sharply, while Euonymus japonica exhibited mild reductions compared to plants grown in control when increasing calcium chloride was used. Especially, the transpiration rates of Rhododendron indicum, and the photosynthesis and stomatal conduct of Buxus koreana were suppressed as the concentrations of calcium chloride increased. Therefore, Euonymus japonica should be considered as an ecologically tolerant species with proven tolerance to de-icing salt.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.2
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• pp.108-113
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• 2017

A sudden cardiac death (SCD) is defined as an unnatural sudden death caused by heart disease. To determine the cause of death, observation of the microscopic change in cardiac muscle tissue is suggested, rather than visual postmortem examination. However, this suggestion is time consuming to be applied in the field, is cost-ineffective, and is inconvenient. Therefore, the purpose of this study is to understand whether temporary inspection used to examine the cardiac marker (Myoglobin, CK-MB, cTn I) in postmortem blood via rapid cardiac triple test kit (which is used by clinics to diagnose patients with acute myocardial infarction) can effectively be utilized for the paragnosis of sudden, unnatural cardiac death. The results of postmortem examination and temporary investigation found that 23 groups (76.7%), among the 30 experimental groups, were assumed to be non-traumatic sudden cardiac deaths, which indicated a positive response (according to comparison with forensic autopsy); 4 groups, among the 10 control groups, were assumed to be cerebrovascular disease, which indicated a negative response; 1 group was assumed to be alcoholic and drug poisoning, indicating a positive response; and 1 group was assumed to be oxygen deficiency due to suffocation, indicating a positive response. Hence, it was found that the level of sensitivity and specificity of cardiac marker's temporary inspection showed significant result, 76.7% and 80% respectively. Given this, temporary inspection can be effectively used for the paragnosis of sudden cardiac death when the medical history, situation of the site, and postmortem interval are considered together. With the result of precedent research on time of first revelation and extinction in blood, and difference in concentration over time progress according to the characteristic of cardiac marker's (myoglobin, CK-MB, cTn I) individual material, further research on concentration of cardiac marker per each post time needs to be conducted in order to estimate time science death (which is required to identify the cause of death and investigation).

• Economic and Environmental Geology
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• v.49 no.6
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• pp.459-467
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• 2016

Due to the limited areal space for installation, borehole heat exchangers (BHEs) at depths deeper than 300 m are considered for geothermal heating and cooling in the urban area. The deep vertical closed-loop BHEs are unconventional due to the depth and the range of the typical installation depth is between 100 and 200 m in Korea. The BHE in the study consists of 50A (outer diameter 50 mm, SDR 11) PE U-tube pipe in a 150 mm diameter borehole with the depth of 300 m. In order to compensate the buoyancy caused by the low density of PE pipe ($0.94{\sim}0.96g/cm^3$) in the borehole filled with ground water, 10 weight band sets (4.6 kg/set) were attached to the bottom of U-tube. A thermal response test (TRT) and fundamental basic surveys on the thermophysical characteristics of the ground were conducted. Ground temperature measures around $15^{\circ}C$ from the surface to 100 m, and the geothermal gradient represents $1.9^{\circ}C/100m$ below 100 m. The TRT was conducted for 48 hours with 17.5 kW heat injection, 28.65 l/min at a circulation fluid flow rate indicates an average temperature difference $8.9^{\circ}C$ between inlet and outlet circulation fluid. The estimated thermophysical parameters are 3.0 W/mk of ground thermal conductivity and 0.104 mk/W of borehole thermal resistance. In the stepwise evaluation of TRT, the ground thermal conductivity was calculated at the standard deviation of 0.16 after the initial 13 hours. The sensitivity analysis on the borehole thermal resistance was also conducted with respect to the PE pipe diameter and the thermal conductivity of backfill material. The borehole thermal resistivity slightly decreased with the increase of the two parameters.

• Tuberculosis and Respiratory Diseases
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• v.62 no.5
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• pp.374-381
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• 2007

Background: This study evaluated which CT findings could be used to predict the negative results of a sputum smear in patients with active pulmonary tuberculosis and multiple cavities. Methods: Thirty-eight patients with active pulmonary tuberculosis and multiple cavities on CT were classified into 2 groups: smear-positive (n = 30) and -negative (n = 8). The CT findings were reviewed retrospectively. The maximum internal diameter of the largest cavity, the number of the cavities and lobes with cavities, and the characteristics of the associated findings such as consolidation, ground glass opacity, micronodules and nodule were accessed. The number of cavities above 20 mm in the maximum internal diameter and a necrotizing pneumonia-like pattern were also evaluated. Result: The maximum internal diameter and number of cavities was $32.23{\pm}17.66mm$ and $15.50{\pm}11.12mm$ (p = 0.0042), and $5.53{\pm}3.17$ and $2.43{\pm}1.13$ (p = 0.0002) in the smear-positive and -negative group, respectively. Three or more cavities were observed at 76.7% and 12.5% in the smear-positive and -negative group, respectively (p < 0.005). There were $2.00{\pm}1.34$ and $0.25{\pm}0.46$ (p = 0.001), and $1.5{\pm}1.50$ and $0.38{\pm}0.52$ (p =0.0016) lobes with consolidation and ground glass opacity in the smear-positive and -negative group, respectively. A necrotizing pneumonia-like pattern was observed in 43.3% of the smear-positive group only. The other findings were similar in both two groups. The sensitivity, specificity, positive and negative predictive value for the presence of at least a finding of consolidation, more than 3 cavities or the largest cavity > 20 mm in the maximum internal diameter were 100%, 62.5%, 90.9%, and 100%, respectively. Conclusion: Two cavities 20 mm or less in the maximum internal diameter without consolidation on CT might be associated with a negative result of the sputum smear in patients with active pulmonary tuberculosis and multiple cavities.