• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.3
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• pp.200-206
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• 1985

This field experiment was undertaken to assess the effects of three levels of inclination ($10^{\circ},\;20^{\circ},\;and\;30^{\circ}$) and four rates of $N-P_2O_5-K_2O$ (0-0-0-, 14-10-10, 28-25-25, and 42-40-40kg/10a) on establishment, yield and quality, and botanical compositions of mixed grass-clover sward. This second part is concerned with the soil chemical properties, concentrations and uptake of mineral nutrients, and percent recovery and efficiency of NPK. The results obtained after a two-year experiment are summarized as follows: 1. The pH, exchangeable Mg and Na, and base saturation in the surface soils were decreased by increasing the grade of inclination, whereas organic matter and available $P_2O_5$ tended to be increased. However, the changes in the Ca content and equivalent ratio of $K\sqrt{Ca+Mg}$ were not significant. The pH, exchangeable Ca and Mg, and base saturation were reduced by increasing the NPK rate, whereas available $P_2O_5$, exchangeable K, and equivalent ratio of $K\sqrt{Ca+Mg}$ tended to be increased. 2. The concentrations of mineral nutrients in grasses and weeds were not significantly affected by increasing the grade of slope in hilly pasture, whereas the concentrations of N, K, and Mg in legume were the lowest with the steep slope, which seemed to be related to the low legume yield. The Mg concentrations of all forage species were below the critical level for good forage growth and likelihood of grass tetany. 3. The increase of NPK rate resulted in the increment of N, K and Na concentrations, and the decrease of Mg and Ca in grasses. The P concentration was increased with P application, but there were no differences in that among the P rates applied. It resulted also in a slight increase of K, and a decrease of Mg in legume, but the contents of N, Ca, and Na were not affected by that. On the other hand, it has not affected the mineral contents in weeds except a somewhat increase of N. The mixed forages showed a increase of N and K contents, a decrease of Ca and Mg, and a slight change in P and Na. 4. The percent recovery of N, P and K by mixed forages were greatly decreased by increasing the grade of inclination and NPK rate. They were high in the order; K>N>P. The efficiency of mixed NPK applications was decreased by that. The efficiency of mixed NPK fertilizers absorbed was slightly decreased by the increased rate of NPK, but it was not affected by the grade of inclination.

• Tuberculosis and Respiratory Diseases
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• v.57 no.5
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• pp.419-424
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• 2004

Background : Although bronchodilator reversibility testing is widely performed to diagnose asthma or COPD, there is debate upon its usefulness and methods to differentiate asthma from COPD. The purpose of this study is to elucidate the role of bronchodilator reversibility testing in differentiating asthma from COPD and to confirm which method is better at evaluating bronchodilator reversibility. Methods : 26 asthma patients and 31 COPD patients were reviewed retrospectively. Spirometry was performed before and after bronchodilator inhalation to get $FEV_1$, FVC. To evaluate bronchodilator reversibility, the increase in $FEV_1$ or FVC was expressed as three methods, 'percentage of the baseline value', 'percentage of the predicted value', or 'absolute value'. Area under the ROC curve was measured to compare the three methods. In addition, the criteria of American Thoracic Society (ATS) for bronchodilator reversibility were compared to those of European Respiratory Society (ERS). Results : 1. In differentiating asthma from COPD, 'percentage of the predicted value', or 'absolute value' method was useful but 'percentage of the baseline value' was not. However, the ability to differentiate was weak because areas under the ROC curves by all methods were less than 0.75. 2. The criteria of ERS were superior to those of ATS for bronchodilator reversibility to differentiate asthma from COPD because likelihood ratio (LR) of a positive test by ERS criteria was greater than ATS criteria and because LR of a negative test by ERS criteria was less than ATS criteria. Conclusion : In differentiating asthma from COPD, bronchodilator reversibility testing has a weak role and should be considered as an adjunctive test.

• The Korean Journal of Financial Management
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• v.25 no.1
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• pp.1-22
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• 2008

This study is to evaluate, to the extent to, which advanced currency futures and emerging currency futures markets can predict accurately the future spot rate. To this end, Johansen's the maximum-likelihood cointegration method(1988, 1991) is adopted to test the unbiasedness and efficiency hypothesis. Also, this study is to estimate and compare a quantitative measure of relative efficiency as a ratio of the forecast error variance from the best-fitting quasi-error correction model to the forecast error variance of the futures price as predictor of the spot price in advanced currency futures with in emerging currency futures market. Advanced currency futures is British pound and Japan yen. Emerging currency futures includes Korea won, Mexico peso, and Brazil real. The empirical results are summarized as follows : First, the unbiasedness hypothesis is not rejected for Korea won and Japan yen futures exchange rates. This indicates that the emerging currency Korea won and the advanced currency Japan yen futures exchange rates are likely to predict accurately realized spot exchange rate at a maturity date without the trader having to pay a risk premium for the privilege of trading the contract. Second, in emerging currency futures markets, the unbiasedness hypothesis is not rejected for Korea won futures market apart from Mexico peso and Brazil real futures markets. This indicates that in emerging currency futures markets, Korea won futures market is more efficient than Mexico peso and Brazil real futures markets and is likely to predict accurately realized spot exchange rate at a maturity date without risk premium. Third, this findings show that the results of unbiasedness hypothesis tests can provide conflicting finding. according to currency futures class and forecasts horizon period, Fourth, from the best-fitting quasi-error correction model with forecast horizons of 14 days, the findings suggest the Japan yen futures market is 27.06% efficient, the British pound futures market is 26.87% efficient, the Korea won futures market is 20.77% efficient, the Mexico peso futures market is 11.55%, and the Brazil real futures market is 4.45% efficient in the usual order. This indicates that the Korea won-dollar futures market is more efficient than Mexico peso, and Brazil real futures market. It is therefore possible to concludes that the Korea won-dollar currency futures market has relatively high efficiency comparing with Mexico peso and Brazil real futures markets of emerging currency futures markets.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2465-2472
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• 2014

Background: The American Joint Committee on Cancer (AJCC) published a new staging system ($7^{th}$ edition) in 2009. In our study, we evaluated the survival results and prognostic factors among T4 local advanced non-small cell lung cancer (LA-NSCLC) patients in a large heterogeneous group, in accordance with this new system. Materials and Methods: We retrospectively evaluated the files of 122 T4 N0-3 M0 LA-NSCLC patients, identified according to the new staging system, treated at two centers between November 2003 and June 2012. Variables correlating with univariate survival at p<0.20 were later included in multivariate Cox regression analysis. Here, selection of relevant predictors of survival was carried out in accordance with the likelihood ratio formula with p<0.05 regarded as significant. Results: The median age was 60 and the median follow-up period was 17.4 months. Median overall survival (OS) was 18.3 months, the 1 year overall survival (OS) rate was 72%, and the 5 year OS rate was 28%. Statistically significant predictors of survival were (p<0.20) ECOG-PS (Eastern Cooperative Oncology Group Performance Status), age, T4 factor subgroup, stage and primary treatment in OS univariate analysis. On multivariate analysis for OS ECOG-PS (p=0.001), diagnostic stage (p=0.021), and primary treatment (p=0.004) were significant. In the group receiving non-curative treatment, the median OS was 11.0 months, while it was 19.0 months in the definitive RT group and 26.6 months in the curative treatment group. There was a significant difference between the non-curative group and the groups which had definitive RT and curative operations (respectively p<0.001 and p=0.001) in terms of OS, but not between the groups which had definitive RT and curative operations. The median event free survival (EFS) rate was 9.9 months, with rates of 46% and 19% at 3 and 5 years, respectively. On univariate analysis of EFS rate with ECOG-PS, weight loss and staging, statistical significance was found only for thorax computerized tomography (CT)+18F-fluorodeoxy-glucose positron emission tomography-CT (PET-CT) use, stage and primary treatment (p<0.20). In multivariate analysis with EFS, only the primary treatment was statistically significant (p=0.001). In the group receiving non-curative treatment, the median EFS was 10.5 months while in the curative operation group it was 14.7 months. When all the primary treatment groups were taken into consideration, grade III/IV side effect swas observed in 57 patients (46.6%). Esophagitis was most prominent among those that received definitive radiotherapy. Conclusions: Independent prognostic factors among these 122 heterogeneous LA-NSCLC T4 N0-3 M0 patients were age at diagnosis, ECOG-PS, stage and primary treatment, the last also being a significant prognostic indicator of EFS. Our findings point to the importance of appropriate staging and a multidisciplinary approach with modern imaging methods in this patient group. In those with T4 lesions, treatment selection and the effective use of curative potential should be the most important goal of clinical care.

• Clinical and Experimental Pediatrics
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• v.45 no.12
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• pp.1577-1584
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• 2002

Purpose : Airway inflammation is considered to be a characteristic feature of asthma, and eosinophils are recognized as the most important inflammatory cells. This study aims to assess the importance of blood eosinophil count and serum eosinophil cationic protein(ECP) levels as a noninvasive marker of bronchial hyperresponsiveness(BHR) in children with suspected asthma. Methods : This study used data from 87 subjects with asthma-like symptoms(6-18 years old). The $FEV_1$ and provocative concentration producing a 20% fall in $FEV_1(PC_{20})$ on methacholin inhalation challenge test were measured. Four groups were classified based on $PC_{20}$[Group I : <2 mg/mL; Group II : 2-8 mg/mL; Group III : 8-18 mg/mL; Group IV : (18 mg/mL], and blood eosinophil count and serum ECP levels were analyzed. In addition, subjects were classified based on the cutoff value of $PC_{20}$(BHR positive group : <18 mg/mL; BHR negative group : (18 mg/mL). Then blood eosinophil count and serum ECP level were compared between these two groups. Results : Likelihood ratio test for trends revealed a significant association between the blood eosinophil count or serum ECP level, and the degree of BHR as measured by methacholine $PC_{20}$. Blood eosinophil count or serum ECP level was significantly higher in the BHR(+) group than in the BHR(-) group. Blood eosinophil count had a positive correlation with serum ECP level. Conclusion : Blood eosinophil count and serum ECP level may be a useful non-invasive clinical marker of BHR in subjects with suspected asthma. This supports the hypothesis that BHR in asthma is a consequence of airway eosinophilic inflammation.

• Management & Information Systems Review
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• v.34 no.3
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• pp.17-39
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• 2015

This study examined the structural changes and volatility in the global stock markets using a Markov Regime Switching ARCH model developed by the Hamilton and Susmel (1994). Firstly, the US, Italy and Ireland showed that variance in the high volatility regime was more than five times that in the low volatility, while Korea, Russia, India, and Greece exhibited that variance in the high volatility regime was increased more than eight times that in the low. On average, a jump from regime 1 to regime 2 implied roughly three times increased in risk, while the risk during regime 3 was up to almost thirteen times than during regime 1 over the study period. And Korea, the US, India, Italy showed ARCH(1) and ARCH(2) effects, leverage and asymmetric effects. Secondly, 278 days were estimated in the persistence of low volatility regime, indicating that the mean transition probability between volatilities exhibited the highest long-term persistence in Korea. Thirdly, the coefficients appeared to be unstable structural changes and volatility for the stock markets in Chow tests during the Asian, Global and European financial crisis. In addition, 1-Step prediction error tests showed that stock markets were unstable during the Asian crisis of 1997-1998 except for Russia, and the Global crisis of 2007-2008 except for Korea and the European crisis of 2010-2011 except for Korea, the US, Russia and India. N-Step tests exhibited that most of stock markets were unstable during the Asian and Global crisis. There was little change in the Asian crisis in CUSUM tests, while stock markets were stable until the late 2000s except for some countries. Also there were stable and unstable stock markets mixed across countries in CUSUMSQ test during the crises. Fourthly, I confirmed a close relevance of the volatility between Korea and other countries in the stock markets through the likelihood ratio tests. Accordingly, I have identified the episode or events that generated the high volatility in the stock markets for the financial crisis, and for all seven stock markets the significant switch between the volatility regimes implied a considerable change in the market risk. It appeared that the high stock market volatility was related with business recession at the beginning in 1990s. By closely examining the history of political and economical events in the global countries, I found that the results of Lamoureux and Lastrapes (1990) were consistent with those of this paper, indicating there were the structural changes and volatility during the crises and specificly every high volatility regime in SWARCH-L(3,2) student t-model was accompanied by some important policy changes or financial crises in countries or other critical events in the international economy. The sophisticated nonlinear models are needed to further analysis.

• Journal of Distribution Research
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• v.15 no.4
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• pp.61-85
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• 2010

Introduction: Diffusion is process by which an innovation is communicated through certain channel overtime among the members of a social system(Rogers 1983). Bass(1969) suggested the Bass model describing diffusion process. The Bass model assumes potential adopters of innovation are influenced by mass-media and word-of-mouth from communication with previous adopters. Various expansions of the Bass model have been conducted. Some of them proposed a third factor affecting diffusion. Others proposed multinational diffusion model and it stressed interactive effect on diffusion among several countries. We add a spatial factor in the Bass model as a third communication factor. Because of situation where we can not control the interaction between markets, we need to consider that diffusion within certain market can be influenced by diffusion in contiguous market. The process that certain type of retail extends is a result that particular market can be described by the retail life cycle. Diffusion of retail has pattern following three phases of spatial diffusion: adoption of innovation happens in near the diffusion center first, spreads to the vicinity of the diffusing center and then adoption of innovation is completed in peripheral areas in saturation stage. So we expect spatial effect to be important to describe diffusion of domestic discount store. We define a spatial diffusion model using multinational diffusion model and apply it to the diffusion of discount store. Modeling: In this paper, we define a spatial diffusion model and apply it to the diffusion of discount store. To define a spatial diffusion model, we expand learning model(Kumar and Krishnan 2002) and separate diffusion process in diffusion center(market A) from diffusion process in the vicinity of the diffusing center(market B). The proposed spatial diffusion model is shown in equation (1a) and (1b). Equation (1a) is the diffusion process in diffusion center and equation (1b) is one in the vicinity of the diffusing center. $$\array{{S_{i,t}=(p_i+q_i{\frac{Y_{i,t-1}}{m_i}})(m_i-Y_{i,t-1})\;i{\in}\{1,{\cdots},I\}\;(1a)}\\{S_{j,t}=(p_j+q_j{\frac{Y_{j,t-1}}{m_i}}+{\sum\limits_{i=1}^I}{\gamma}_{ij}{\frac{Y_{i,t-1}}{m_i}})(m_j-Y_{j,t-1})\;i{\in}\{1,{\cdots},I\},\;j{\in}\{I+1,{\cdots},I+J\}\;(1b)}}$$ We rise two research questions. (1) The proposed spatial diffusion model is more effective than the Bass model to describe the diffusion of discount stores. (2) The more similar retail environment of diffusing center with that of the vicinity of the contiguous market is, the larger spatial effect of diffusing center on diffusion of the vicinity of the contiguous market is. To examine above two questions, we adopt the Bass model to estimate diffusion of discount store first. Next spatial diffusion model where spatial factor is added to the Bass model is used to estimate it. Finally by comparing Bass model with spatial diffusion model, we try to find out which model describes diffusion of discount store better. In addition, we investigate the relationship between similarity of retail environment(conceptual distance) and spatial factor impact with correlation analysis. Result and Implication: We suggest spatial diffusion model to describe diffusion of discount stores. To examine the proposed spatial diffusion model, 347 domestic discount stores are used and we divide nation into 5 districts, Seoul-Gyeongin(SG), Busan-Gyeongnam(BG), Daegu-Gyeongbuk(DG), Gwan- gju-Jeonla(GJ), Daejeon-Chungcheong(DC), and the result is shown