• Journal of Periodontal and Implant Science
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• v.24 no.2
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• pp.271-282
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• 1994

Active treatment of periodontal disease consists of plaque control by the patient, with root planing and surgery perfomed by the dental practitioner. Chlorhexidine rinse has been the most effective antiplaque agent available today and tetracycline has been the most favored antibiotics. Therefore, the purpose of this study was compared the different effect among groups(saline mouthrinse[group I], 0.125% chlorhexidine mouthrinse [groupII], and 0.125% chlorhexidine mouthrinse containing tetracycline[groupIII]) during the immediate post periodontal therapy. We assessed plaque index, gingival index, papillary bleediing index, gingival crevicular volume, periodontal attachment loss, and periodontal pocket depth in 3 sites per subject. The assessment was made at baseline. At 1 week after scaling, and at 2 weeks after curettage. All groups were clinically and statistically reduced plaque score, gingival score, papillary bleeding score, and gingival crevicular volume at 2 weeks after curettage. Group II was significantly reduced periodontal pocket depth.(P<0.05) At 1 week after scaling, al clinical index scores were reduced but not singificantly difference between the groups.(p>0.05) At 2 weeks after curettage, plaque score, gingival score and papillary bleeding score were significantly difference between the groups.(P<0.05) During the experimental period, gingiva was not damaged and stain of the tongue or teeth were not noted in all groups.

• Structural Engineering and Mechanics
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• v.60 no.5
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• pp.875-890
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• 2016

A new structural damage index for seismic fragility analysis of reinforced concrete columns is developed based on a local tensile damage variable of the Lee and Fenves plastic-damage model. The proposed damage index is formulated from the nonlinear regression of experimental column test data. In contrast to the response-based damage index, the proposed damage index is well-defined in the form of a single monotonically-increasing function of the volume weighted average of local damage distribution, and provides the necessary computability and objectivity. It is shown that the present damage index can be appropriately zoned to be used in seismic fragility analysis. An application example in the computational seismic fragility evaluation of reinforced concrete columns validates the effectiveness of the proposed damage index.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.3
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• pp.169-174
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• 2021

Today, plastic waste has become a critical social issue due to the increasing of plastic consumption. Korean annual per capita plastic consumption was 132 kg, the most plastic consuming country in the world. Internationally, Carbon Neutral Agreement is underway due to global warming, consumers' interest and needs for biomass-based plastics has also been increased. In this study, film was produced by adding composite use additives to the biomass-based plastics according to concentration, and the resulting changes in discharge volume, melt index, and tensile strength were investigated. Melt index (MI) was significantly higher in PLA and PBAT than in petroleum-based resin LLDPE and LDPE. Also, among the same resin or in the same treatment group, MI has been increased when the heating temperature is increased. The discharge volume and gravity of the BDP-2 to which 4% compatibilizer was added were found to be higher among all treatments, while the tensile strength of MD and TD was also higher. BDP-2 was suitable to the film producing methods for biodegradable film production.

• Journal of Cardiovascular Imaging
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• v.31 no.2
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• pp.96-97
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• 2023

• The Korean Journal of Financial Management
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• v.24 no.2
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• pp.41-79
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• 2007

This study examines the expiration-day effects of stock index futures and options in the Korean stock market. The so-called 'expiration-day effects', which are the abnormal stock price movements on derivatives expiration days, arise mainly from cash settlement. Index arbitragers have to bear the risk of their positions unless they liquidate their index stocks on the expiration day. If many arbitragers execute large buy or sell orders on the expiration day, abnormal trading volumes are likely to be observed. If a lot of arbitragers unwind positions in the same direction, temporary trading imbalances induce abnormal stock market volatility. By contrast, if some information arrives at market, the abnormal trading activity must be considered a normal process of price discovery. Stoll and Whaley(1987) investigated the aggregate price and volume effects of the S&P 500 index on the expiration day. In a related study, Stoll and Whaley(1990) found a similarity between the price behavior of stocks that are subject to program trading and of the stocks that are not. Thus far, there have been few studies about the expiration-day effects in the Korean stock market. While previous Korean studies use the KOSPI 200 index data, we analyze the price and trading volume behavior of individual stocks as well as the index. Analyzing individual stocks is important for two reasons. First, stock index is a market average. Consequently, it cannot reflect the behavior of many individual stocks. For example, if the expiration-day effects are mainly related to a specific group, it cannot be said that the expiration of derivatives itself destabilizes the stock market. Analyzing individual stocks enables us to investigate the scope of the expiration-day effects. Second, we can find the relationship between the firm characteristics and the expiration-day effects. For example, if the expiration-day effects exist in large stocks not belonging to the KOSPI 200 index, program trading may not be related to the expiration-day effects. The examination of individual stocks has led us to the cause of the expiration-day effects. Using the intraday data during the period May 3, 1996 through December 30, 2003, we first examine the price and volume effects of the KOSPI 200 and NON-KOSPI 200 index following the Stoll and Whaley(1987) methodology. We calculate the NON-KOSPI 200 index by using the returns and market capitalization of the KOSPI and KOSPI 200 index. In individual stocks, we divide KOSPI 200 stocks by size into three groups and match NON-KOSPI 200 stocks with KOSPI 200 stocks having the closest firm characteristics. We compare KOSPI 200 stocks with NON-KOSPI 200 stocks. To test whether the expiration-day effects are related to order imbalances or new information, we check price reversals on the next day. Finally, we perform a cross-sectional regression analysis to elaborate on the impact of the firm characteristics on price reversals. The main results seem to support the expiration-day effects, especially on stock index futures expiration days. The price behavior of stocks that are subject to program trading is shown to have price effects, abnormal return volatility, and large volumes during the last half hour of trading on the expiration day. Return reversals are also found in the KOSPI 200 index and stocks. However, there is no evidence of abnormal trading volume, or price reversals in the NON-KOSPI 200 index and stocks. The expiration-day effects are proportional to the size of stocks and the nearness to the settlement time. Since program trading is often said to be concentrated in high capitalization stocks, these results imply that the expiration-day effects seem to be associated with program trading and the settlement price determination procedure. In summary, the expiration-day effects in the Korean stock market do not exist in all stocks, but in large capitalization stocks belonging to the KOSPI 200 index. Additionally, the expiration-day effects in the Korean stock market are generally due, not to information, but to trading imbalances.

• The Korean Journal of Nuclear Medicine
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• v.3 no.2
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• pp.1-16
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• 1969

The double tracer study on erythrokinetics was carried out experimentally with radioactive iron ($^{59}Fe$) and chromium ($^{51}Cr$) in rabbits. The 0.1% canthalidin solution and 1% pot. perchlomate solution was given subcutaneously to 20 rabbits respectively. 3 and 6 days after injection, the blood chemistry, urine examination, ferrokinetics and apparent half survival time of RBC were ($^{51}Cr\;T\frac{1}{2}$)determined. Following were the results: 1) Red blood cell hematocrit and hemoglobin values were moderately reduced and B.U.N. and serum creatinine values were slight]y inercased in the canthalidin group, while B.U.N. and serum creatinine values were within normal limits in the pot. perchlomate group. Reticulocyte values were slight]y increased in the canthalidin group, while was normal range in the pot. perchlomate group. 2) Blood chemistry finding was not significant statistically in both experimental groups, but serum iron value was moderately reduced in both group. 3) Plasma volume was unchanged in both group, but red cell volume and whole blood volume were slightly reduced in both groups. 4) Results of ferrokinetics were as follows: i) The plasma iron disappearance rate was delayed in both groups. Plasma iron turnover rate, red cell iron utilization and red cell iron turnover rate were decreased in both groups, and then red cell iron turnover rate was more decreased than plasma iron turnover rate in both groups. Circulating red cell iron was slight]y increased in canthalidin group and red cell iron concentration was within normal range in both groups. ii) P.I.T.R.-R.C.I.T. value was moderately increased in the canthalidin group and slightly increased in the pot. perchlomate group. Reticulocyte index, red cell iron turnover index, plasma iron turnover index and effective erythropoiesis index were whole]y reduced in both groups. iii) The red cell life span was slightly shortened in the canthalidin group while was within normal range in pot. perchlomate group. The pathologic finding of renal biopsy of the canthalidin group shows a selective damage in glomerulus, while shows almost normal range or slight damage in tubules. And that of the pot. perchlomate group shows a selective damage in tubules with slight damage of glomerulus.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.1
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• pp.21-28
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• 2014

Purpose : For non-small cell lung cancer, if the treatment volume is large or the total lung volume is small, and the tumor is located in midline of patient's body, total lung dose tends to increase due to tolerance dose of spinal cord. The purpose of this study is to compare and evaluate the total lung dose of three dimensional conformal radiotherapy(3D CRT), intensity modulated radiotherapy(IMRT) and volumetric modulated arc therapy(VMAT) using restricted angle for non-small cell lung cancer patients. Materials and Methods : The treatment plans for four patients, being treated on TrueBeam STx($Varian^{TM}$, USA) with 10 MV and prescribed dose of 60 Gy in 30 fractions, 3D CRT, restricted angle IMRT and VAMT radiotherapy plans were established. Planning target volume(PTV), dose to total lung and spinal cord were evaluated using the dose volume histogram(DVH). Conformity index(CI), homogeneity index(HI), Paddick's index(PCI) for the PTV, $V_{30}$, $V_{20}$, $V_{10}$, $V_5$, mean dose for total lung and maximum dose for spinal cord was assessed. Results : Average value of CI, HI and PCI for PTV was $0.944{\pm}0.009$, $1.106{\pm}0.027$, $1.084{\pm}0.016$ respectively. $V_{20}$ values from 3D CRT, IMRT and VMAT plans were 30.7%, 20.2% and 21.2% for the first patient, 33.0%, 29.2% and 31.5% for second patient, 51.3%, 34.3% and 36.9% for third patient, finally 56.9%, 33.7% and 40.0% for the last patient. It was noticed that the $V_{20}$ was lowest in the IMRT plan using restricted angle. Maximum dose for spinal cord was evaluated to lower than the tolerance dose. Conclusion : For non-small cell lung cancer, IMRT with restricted angle or VMAT could minimize the lung dose and lower the dose to spinal cord below the tolerance level. Considering PTV coverage and tolerance dose to spinal cord, it was possible to obtain IMRT plan with smaller angle and this could result in lower dose to lung when compared to VMAT.

• KIEAE Journal
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• v.17 no.1
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• pp.23-28
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• 2017

Purpose: Many design index that are using in planning phase have been developed. The most popular things among them are Window to Wall Ratio and Surface to Volume Ratio. However there are some limits. Window to Wall Ratio cannot consider building size and Surface to Volume Ratio cannot do Window to Wall Ratio. Accordingly, in this paper, the Window to Floor Ratio was proposed that it can be considered both building size and Window to Wall Ratio. And analyzed correlation of energy demand. Method: For the test, 16 modules with the size of $6m{\times}6m{\times}4m$ were used to make 35 models with the same volume. The simulation was conducted to 945 cases using the window-to-wall ratio of 30, 50 and 70 % in three areas such as Seoul, Gwangju and Jeju and three kinds of windows. And IES_VE was used. Result: The findings above show that the Window to Floor Ratio that can be considered both building size and Window area have to become as design index. It was found out that design criteria with SHGC is necessary, not with the thermal performance (U-value). It is needed to additional analysis about residential building and the effect of 24-hours heating and cooling condition. It plans to carry out research to establish design indicators for climatic conditions in the country and building applications.

• Journal of Forest and Environmental Science
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• v.29 no.4
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• pp.282-291
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• 2013

Rapid loss in viability of neem (Azadirachta indica A. Juss.) seed is a major problem. Present effort was undertaken for developing a set pattern for assessing of viability and vigour in seed of various mother tree age of neem (Age I-06 years, Age II-15 years, Age III-25 years and Age IV->30 years old). Various viability test viz. triphenyle tetrazolium chloride test, electrical conductivity, excised embryo test, and germination test have been performed on seeds obtained from mother tree age classes. Inconsistency was observed with the TTC and EC test in germination of seed in laboratory as well as nursery. While various vigour tests viz. cold test, chemical stress test (methanol stress test), and accelerated ageing test alongwith ageing index, germination test (G%, MGT and GV) and various seedling growth parameters like seedling length (cm), number of leaves, collar diameter (cm), total biomass (g) alongwith mathematical indices i.e. vigour index, sturdiness quotient, volume index, quality index, root shoot ratio in nursery as well have been taken for study and showed better consistency. On the basis present study results of various viability and vigour test indicated that mother tree age class II performed better in comparison to others and it can be recommended for seed collection. Further it is also recommended that viability of neem seed may be assessed using various laboratory tests like excise embryo test and germination test (G%, MGT and GV) and vigour test may be taken preferably by cold germination test, chemical (methanol) stress test, accelerated ageing test in laboratory and germination alongwith various seedling growth parameters seedling length (cm), number of leaves, collar diameter (cm), total biomass (g) alongwith mathematical indices like Vigour Index, Sturdiness quotient, Volume Index, Quality index, root shoot ratio in nursery as discussed in this study.

• Journal of Forest and Environmental Science
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• v.24 no.1
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• pp.41-46
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• 2008

Progeny tests of Abies holophylla were established with 32 open-pollinated families at Hwaseong and Gangneung in 1994. Growth characteristics (height, DBH and volume index) were measured at the age of 15, showing that Gangneung site showed in general better performance than Hwaseong site. Analysis of variance (ANOVA) of the growth characteristics showed that there was a significant difference among families in Gangneung but not in Hwaseong, and Hwaseong site showed that DBH and volume index were statistically different among replications. At Gangneung site, family ${\times}$ replication interaction was significant in DBH and volume index. Based on the combined analysis of both sites, all characteristics except height showed highly significant differences between sites and among families. On the other hand, family ${\times}$ replication interaction was not significant, implying that growth pattern of families could be similar at Gangneung and Hwaseong. Individual heritabilities ($hi^2$) at Gangneung were 0.485 in height, 0.611 in DBH and 0.538 in volume index, and the values of $hi^2$ at Hwaseong were 0.121 in height, 0.054 in DBH and 0.080 in volume index, respectively. Based on both sites, $hi^2$ was estimated as 0.204 in height, 0.326 in DBH and 0.238 in volume index. Individual heritabilities (0.054~0.611) were lower than family heritabilities (0.089~0.723) for all growth characteristics. Realized gain was estimated to be 2.5% in height, 9.2% in DBH and 23.6% in volume. When inferior families (about 50% of all families) are genetically thinned from a seed orchard, genetic gain would be 9.55% in height, 17.0% in DBH and 46.8% in volume.