• Journal of the Korean earth science society
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• 제35권1호
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• pp.1-18
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• 2014

The purpose of this study was to analyze the sensitivity of meteorological fields and the variation of concentration of particulate matters (PMs) due to aerosol schemes and dust options within the WRF-Chem model to estimate Asian dusts affected on 29 May 2008 in the Korean peninsula. The anthropogenic emissions within the model were adopted by the $0.5^{\circ}{\pm}0.5^{\circ}$ RETRO of the global emissions, and the photolysis option was by Fast-J photolysis. Also, three scenarios such as the RADM2 chemical mechanism and MADE/SORGAM aerosol, the MOSAIC 8 section aerosol, and the GOCART dust erosion were simulated for calculating Asian dust emissions. As a result, the scenario of the RADM2 chemical mechanism & MADE/SORGAM aerosol depicted higher concentration than the others' in both Asian dusts and the background concentration of PMs. By comparing of the daily mean of PM10 measured at each air quality monitoring site in Seoul with the scenario results, the correlation coefficient was 0.67, and the root mean square error was $44{\mu}gm^{-3}$. In addition, the air temperature, the wind speed, the planetary boundary layer height, and the outgoing long-wave radiation were simulated under conditions of no chemical option with these three scenarios within the WRF or WRF-Chem model. Both the spatial distributions of the PBL height and the wind speed of u component among the meteorological factors were similar to those of the Asia dusts in range of 1,800-3,000 m and $2-16ms^{-1}$, respectively. And, it was shown that both scenarios of the RADM2 chemical mechanism and MADE/SORGAM aerosol and the GOCART dust erosion were interacted on-line between meteorological factors and Asian dusts or aerosols within the model because the outgoing long-wave radiation was changed to lower than the others.

• Journal of the Korean Institute of Landscape Architecture
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• 제46권3호
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• pp.70-78
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• 2018

Recently, the conservation of mountainous landscape and compensation for diverse demands for mountain areas such as leisure, recreation and welfare are under discussion. The purpose of this study is to investigation the perception of mountainous landscapes by those who view and recognize the landscapes and to estimate economic value by estimating the willingness to pay for the management of mountainous landscapes. This study will provide data for the management of mountainous landscapes. As a result of comparing the perception between the territorial landscape and the mountain landscape, the mountain scenery was 3.96, the management level satisfaction was 3.28, and the management necessity was 4.38, which was higher than the national landscape, while the national landscape was satisfactory but the management level was insufficient. Jeju Island (39.0%) and Gangwon (38.6%) were chosen as the most scenic areas with beautiful forest and mountainous landscape resources. The aesthetic characteristics of the vast skyline of mountain scenery, the background of the area, and the mountainous landscape that forms the landmark were evaluated highly. And, it is considered that consciousness of mountainous landscape management is heightened by 86.8% of respondents, who positively answered the Mountainous Landscape Visual Impact Assessment before the development project. The per capita payment amount for mountainous landscape management was calculated to be 3,742 won and, based on the number of visitors to the mountain National Parks in 2016, it is estimated to have an economic value of about 169.5 billion won. Policymakers have limitations in the mountainous landscape management policies of the administrative subject. Establishing a consensus on the importance and necessity of landscape management by diagnosing the status of public perception is expected to help create more effective policy direction and implement strategies for the management of these areas.

• Journal of the Korean Society for Marine Environment & Energy
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• 제19권4호
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• pp.322-331
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• 2016

Oil budget calculator identifies the removal pathways of spilled oil by both natural and response methods, and estimates the remaining oil required response activities. A oil budget calculator was newly developed as a response tool for Deepwater Horizon oil spill incident in Gulf of Mexico in 2010 to inform clean up decisions for Incident Comment System, which was also successfully utilized to media and general public promotion of oil spill response activities. This study analyzed the theoretical background of the oil budget calculator and explored its future application to Korea. The oil budge calculation of four catastrophic marine pollution incidents indicates that 3~8% of spilled oil was removed mechanically by skimmers, 1~5% by in-situ burning, 4.8~16% by chemical dispersion due to dispersant operation, and 37~56% by weathering processes such as evaporation, dissolution, and natural dispersion. The results show that in-situ burning and chemical dispersion effectively remove spilled oil more than the mechanical removal by skimming, and natural weathering processes are also very effective to remove spilled oil. To apply the oil budget calculator in Korea, its parameters need to be optimized in response to the seasonal characteristics of marine environment, the characteristics of spilled oil and response technologies. A new algorithm also needs to be developed to estimate the oil budget due to shoreline cleanup activities. An oil budget calculator optimized in Korea can play a critical role in informing decisions for oil spill response activities and communicating spill prevention and response activities with the media and general public.

• Asian Pacific Journal of Cancer Prevention
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• 제15권1호
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• pp.391-395
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• 2014

Background: We aimed to evaluate the role of genetic polymorphisms in tobacco carcinogen-metabolizing genes and their interactions with smoking in a hospital-based case-control study of Japanese subjects. Materials and Methods: We examine the associations of pancreatic cancer risk with genetic polymorphisms in GSTM1, GSTT1 and GSTP1, phase II enzymes that catalyze the conjugation of toxic and carcinogenic electrophilic molecules. The study population consisted of 360 patients and 400 control subjects, who were recruited from several medical facilities in Japan. Unconditional logistic regression methods were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between genotypes and pancreatic cancer risk. Results: Among the control subjects, the prevalence of the GSTM1-null genotype and the GSTT1-null genotype was approximately 56% and 48%, respectively. Cases and controls were comparable in terms of GSTM1 and GSTT1 genotype distributions. Neither of the deleted polymorphisms in GSTM1 and GSTT1 was associated with the risk of pancreatic cancer, with an age- and sex-adjusted OR of 0.99 (95%CI: 0.74-1.32) for the GSTM1-null genotype, and 0.98 (95%CI: 0.73-1.31) for the GSTT1-null genotype. The OR was 0.97 (95%CI: 0.64-1.47) for individuals with the GSTM1 and GSTT1-null genotypes compared with those with the GSTM1 and GSTT1- present genotypes. No synergistic effects of smoking or GST genotypes were observed. Conclusions: Our results indicate no overall association between the GSTM1 and GSTT1 deletion polymorphisms and pancreatic cancer risk in the Japanese subjects in our study.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1291-1298
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• 2014

Background: Evidence for associations between dietary factors and breast cancer risk is inconclusive among Chinese females. To evaluate this question, we conducted a systematic review of relevant case-control and cohort studies. Methods: Studies were systematically searched among 5 English databases (PudMed, ScienceDirect, Wiley, Clinicaltrials.gov, and Cochrane) and 3 Chinese databases (CNKI, WanFang, and VIP) until November 2012. Random effects models were used to estimate summary odds ratios (ORs) and the corresponding 95% confidence intervals (CIs). Results: Thirty one case-control studies and two cohort studies involving 9,299 cases and 11,413 controls were included. Consumption of both soy and fruit was significantly associated with decreased risk of breast cancer, with summary ORs of 0.65 (95% CIs: 0.43-0.99; I2=88.9%, P<0.001; N=13) and 0.66 (95% CIs: 0.47-0.91; $I^2$=76.7%, P<0.001; N=7), respectively. Consumption of fat was significantly associated with increased risk of breast cancer (OR=1.36; 95% CIs: 1.13-1.63; $I^2$=47.9%, P=0.088; N=6). There was nonsignificant association between consumption of vegetables and breast cancer risk (OR=0.72; 95% CIs: 0.51-1.02; $I^2$= 74.4%, P<0.001; N=9). However, sensitivity analysis based on adjusted ORs showed decreased risk of breast cancer was also associated with consumption of vegetables (OR=0.49; 95% CIs: 0.30-0.67). Conclusion: Both soy food and fruit are significantly associated with decreased risk of breast cancer among Chinese females, and vegetables also seems to be protective while dietary fatexerts a promoting influence.

• Journal of Intelligence and Information Systems
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• 제17권4호
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• pp.157-173
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• 2011

As the Internet use explodes recently, the malicious attacks and hacking for a system connected to network occur frequently. This means the fatal damage can be caused by these intrusions in the government agency, public office, and company operating various systems. For such reasons, there are growing interests and demand about the intrusion detection systems (IDS)-the security systems for detecting, identifying and responding to unauthorized or abnormal activities appropriately. The intrusion detection models that have been applied in conventional IDS are generally designed by modeling the experts' implicit knowledge on the network intrusions or the hackers' abnormal behaviors. These kinds of intrusion detection models perform well under the normal situations. However, they show poor performance when they meet a new or unknown pattern of the network attacks. For this reason, several recent studies try to adopt various artificial intelligence techniques, which can proactively respond to the unknown threats. Especially, artificial neural networks (ANNs) have popularly been applied in the prior studies because of its superior prediction accuracy. However, ANNs have some intrinsic limitations such as the risk of overfitting, the requirement of the large sample size, and the lack of understanding the prediction process (i.e. black box theory). As a result, the most recent studies on IDS have started to adopt support vector machine (SVM), the classification technique that is more stable and powerful compared to ANNs. SVM is known as a relatively high predictive power and generalization capability. Under this background, this study proposes a novel intelligent intrusion detection model that uses SVM as the classification model in order to improve the predictive ability of IDS. Also, our model is designed to consider the asymmetric error cost by optimizing the classification threshold. Generally, there are two common forms of errors in intrusion detection. The first error type is the False-Positive Error (FPE). In the case of FPE, the wrong judgment on it may result in the unnecessary fixation. The second error type is the False-Negative Error (FNE) that mainly misjudges the malware of the program as normal. Compared to FPE, FNE is more fatal. Thus, when considering total cost of misclassification in IDS, it is more reasonable to assign heavier weights on FNE rather than FPE. Therefore, we designed our proposed intrusion detection model to optimize the classification threshold in order to minimize the total misclassification cost. In this case, conventional SVM cannot be applied because it is designed to generate discrete output (i.e. a class). To resolve this problem, we used the revised SVM technique proposed by Platt(2000), which is able to generate the probability estimate. To validate the practical applicability of our model, we applied it to the real-world dataset for network intrusion detection. The experimental dataset was collected from the IDS sensor of an official institution in Korea from January to June 2010. We collected 15,000 log data in total, and selected 1,000 samples from them by using random sampling method. In addition, the SVM model was compared with the logistic regression (LOGIT), decision trees (DT), and ANN to confirm the superiority of the proposed model. LOGIT and DT was experimented using PASW Statistics v18.0, and ANN was experimented using Neuroshell 4.0. For SVM, LIBSVM v2.90-a freeware for training SVM classifier-was used. Empirical results showed that our proposed model based on SVM outperformed all the other comparative models in detecting network intrusions from the accuracy perspective. They also showed that our model reduced the total misclassification cost compared to the ANN-based intrusion detection model. As a result, it is expected that the intrusion detection model proposed in this paper would not only enhance the performance of IDS, but also lead to better management of FNE.

• Asian Pacific Journal of Cancer Prevention
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• 제17권8호
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• pp.3785-3791
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• 2016

Background: Previous studies have assessed the association between the Cytotoxic T-lymphocyte Antigen-4(CTLA-4) polymorphism with the risk of malignant bone tumor, but the conclusions were inconsistent. We aimed to clarify association of cytotoxic T-lymphocyte antigen-4 polymorphisms with malignant bone tumors risk by performing a meta-analysis. Materials and Methods: The databases including PubMed, EMBase databases and the Cochrane Library were searched to identify the eligible studies prior to January 30 2016. Odds ratio (OR) with 95% confidence interval (95%CI) were used to estimate the strengths of the association between the CTLA-4 polymorphism and the malignant bone tumor risks. The meta-analysis was performed by STATA 12.0. Results: Four individual studies with a total of 1003 cases with malignant bone tumor and 1162 controls were included in our meta-analysis. The results of meta-analysis on those data demonstrated that CTLA-4 +49G>A polymorphism was associated with the risk of Ewing's sarcoma and osteosarcoma strongly (A vs. G: OR=1.36, 95%CI:1.20-1.54, p=0.000; AA+AG vs. GG: OR=1.35, 95%CI:1.14-1.61, p=0.001; AA vs. GG: OR=2.24, 95%CI:1.67-2.99, p=0.000; AA vs. AG+GG: OR=2.00, 95%CI:1.53-2.62, p=0.000), but CTLA-4 -318C/T polymorphism was not associated with the risk of malignant bone tumor (C vs. T: OR=0.76, 95%CI:0.76-1.08, p= 0.262; CC+CT vs. TT: OR=0.70, 95%CI:0.41-1.20, p= 0.198; CC vs. TT: OR=0.69, 95%CI:0.40-1.19, p= 0.183; CC vs. CT+TT: OR=0.92, 95%CI:0.75-1.13, p= 0.419). Subgroup analysis showed that there are significantly positive correlations between CTLA-4 +49G>A polymorphism and increased risks of malignant bone tumors in large size of sample (A vs. G: OR=1.347, 95%CI: 1.172,1.548, p=0.000; AA vs. GG: OR=2.228, 95%CI: 1.608,3.085, p=0.000), Ewing's Sarcoma or Osteosarcoma (A vs. G: OR=1.361, 95%CI: 1.201,1.540, p=0.000; AA vs. GG: OR=2.236, 95%CI: 1.674,2.986, p=0.000), and PCR-RFLP or Sequencing(A vs. G: OR=1.361, 95%CI: 1.201,1.540, p=0.000; AA vs. GG: OR=2.236, 95%CI: 1.674,2.986, p=0.000), but CTLA-4 -318C/T polymorphism was not associated with the risk of malignant bone tumors in diagnosis, genotype method, and sample size (all p>0.05). Conclusions: CTLA-4 +49A/G variant was associated with an increased risk of developing the malignant bone tumors, such as Ewing's sarcoma and osteosarcoma. However, it failed to show the association between CTLA-4 -318C/T polymorphism and the risk of malignant bone tumors. Future large-scale studies remain to be done to confirm our conclusions.

• Journal of the Korea Concrete Institute
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• 제25권3호
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• pp.321-329
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• 2013

Recently, the medium-low level radioactive waste from nuclear power plant must be transported from temporary storage to the final repository. Medium-low level radioactive waste, which is composed mainly of the liquid ion exchange resin, has been consolidated with cementitious material in the plastic or iron container. Since cementitious material is brittle, it would generate cracks by impact load during transportation, signifying leakage of radioactive ray. In order to design the safety transporting equipment, there is a need to check the compressive strength of the current waste. However, because it is impossible to measure strength by direct method due to leakage of radioactive ray, we will estimate the strength indirectly by the dynamic modulus of elasticity. Therefore, it must be identified the relationship between of strength and dynamic modulus of elasticity. According to the waste acceptance criteria, the compressive strength of cement based solid is defined as more than 3.44 MPa (500 psi). Compressive strength of the present solid is likely to be significantly higher than this baseline because of continuous hydration of cement during long period. On this background, we have tried to produce the specimens of the 28 day's compressive strength of 3 to 30 MPa having the same material composition as the solid product for the medium-low level radioactive waste, and analyze the relationship between the strength and the dynamic modulus of elasticity. By controling the addition rates of AE agent, we made the mixture containing the ion exchange resin and showing the target compressive strength (3~30 MPa). The dynamic modulus of elasticity of this mixtures is 4.1~10.2 GPa, about 20 GPa lower in the equivalent compressive strength level than that of ordinary concrete, and increasing the discrepancy according to increase strength. The compressive strength and the dynamic modulus of elasticity show the liner relationship.

• Tuberculosis and Respiratory Diseases
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• 제51권4호
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• pp.325-333
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• 2001

Background : This study aimed to estimate the clinical outcome and identify the characteristics of a group of patients with pulmonary tuberculosis who completed anti-tuberculosis therapy with the First-line drugs in spite of having positive smear results with negative sputum culture results over the previous six months. Method : A retrospective chart review of 21 patients who fulfilled the above criteria between 1995 and 1999 was performed. The laboratory data as well as the clinical data of the patients with positive smear results and negative culture results over a six months period were reviewed. Results : The negative conversion of sputum culture results was achieved within $1.3{\pm}1.2$ months and the negative conversion of the sputum smear results was accomplished during $9.5{\pm}3.3$ months. Chest X-rays at 5 months following the institution of anti-tuberculosis therapy from all patients revealed improvements. Four out of 21 patients(19%) relapsed during the follow up, $15.2{\pm}13.4$ months after administering anti-tuberculosis therapy for $13.3{\pm}3.1$ months. Relapses were confirmed from between 3 months and 4 months after the treatment completion. Only one of the four relapses had no past history of anti-tuberculosis therapy and the others had prior treatment twice (p<0.01). The period of anti-tuberculosis treatment was extended to a mean of $4.6{\pm}2.6$ months in 12 patients. However, prolongation of anti-tuberculosis therapy had no affect on the relapse rate (odds ratio, 95% CI 0.18, 2.15). Conclusion : Prolongation of therapy with the First-line drugs is not necessary for patients with persistently positive smear results over 6 months and negative culture results. A patient who has had prior anti-tuberculosis therapy more than twice should be paid the closest attention.

• Tuberculosis and Respiratory Diseases
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• 제46권2호
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• pp.165-174
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• 1999

Background: Coal-worker's pneumoconiosis(CWP) is radiologically divided into two major groups: simple pneumoconiosis (SP), in which small, rounded or irregular opacities smaller than 1cm are observed, and progressive massive fibrosis(PMF), which is characterized by opacities larger than 1cm. SP has a life expectancy equivalent to miners with no radiographic evidence of CWP, but PMF is associated with more obvious impairments of ventilatory capacity and premature death. But only minority of workers develop PMF when exposed to dust concentrations similar to those experienced by workers who develop only SP. In this study, immune status in patients with CWP were evaluated by measurement of the serum immunoglobulin levels between control, SP and PMF groups. Method: Coal workers selected for this study were emplyees of the Tae-Baek and Dong-Hae Hospital. All the patients were men of 45-76 years old and the mean duration of exposure to coal dust were 23.2 years. By X-ray examination, 51 patients were classified in SP, 59 in PMF category. The normal controls examined were 58 men of 26-70 years old. Serum Ig levels were estimated by using Nephelometer(Behring Nephelometer : Germany) and serum were collected 51 in SP, 49 in PMF and 57 cases in control group. Results: The levels of IgG were increased but the levels of IgM were decreased with increasing age in control groups. There were no statistical difference of immunoglobulin levels between smokers and nonsmokers in control groups. There were no statistical difference of immunoglobulin levels between Control, SP and PMF groups. Multiple regression analysis were undertaken to determine the statistical significance of the apparent trends and estimate the effects associated with age, smoking habit and radiological category of CWP. According to this analysis, the levels of IgG were decreased significantly in SP group and had decreasing tendancy, but not statistically significant in PMF group. Conclusion : From the observations described, CWP patients had decreased IgG concentration compared to control gorup. Therefore, there was some relation between CWP and immunoglobulin concentration.