• Journal of Korean Society on Water Environment
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• v.25 no.1
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• pp.69-75
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• 2009

Water stress has become a major concern in agriculture. Korea suffers from limited agricultural water supply, and wastewater reuse has been recommended as an alternative solution. A study was performed to examine the effects of microorganism concentration in the ponded-water of a paddy rice field with reclaimed-water irrigation for evaluating the microbial risk to farmers and neighborhood children. Most epidemiological studies were performed based on an upland field, and they may not directly applicable to paddy fields. Beta-Poisson model was used to estimate the microbial risk of pathogen ingestion. Their risk value increased significantly high level after irrigation and precipitation. It implies that agricultural activities such as plowing, and fertilizing, and precipitation need be practiced a few days after irrigation considering health risks. The results about field application of the microbial risk assessment using E. coli showed difference according to monitoring time and treatment plot. Result of the microbial risk assessment showed that risk values of ground-water and reclaimed secondary wastewater irrigation were lower than directly use of wastewater treatment plants' effluent. This paper should be viewed as a first step in the application of quantitative microbial risk assessment of E. coli to wastewater reuse in a paddy rice farming.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.537-540
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• 2015

Background: Ovarian cancer is recognized as the fourth leading cancer in Malaysia. However, women do not always seek help in a timely manner and gaps in awareness may influence screening uptake and presentation. The purpose of this study was to determine levels of awareness of ovarian cancer risk factors in female population in Penang, Malaysia. Materials and Methods: A cross-sectional study was conducted in Penang, Malaysia from January until February 2014. Eighty-seven women were selected by convenient sampling. Awareness of risk factors of ovarian cancer was assessed using a self-administered questionnaire. Data were analyzed using statistical package for the social sciences (SPSS) version 20.0 for descriptive statistics and Pearson chi-square test for the association between socio-demographic data and awareness. A p value ${\leq}0.05$ was considered statistically significant. Results: In all, 74.7% of participants answered correctly for the risk factor of increasing age, although 94.3% were unaware of increased risk of tall women. A majority, 71.3%, had a low level of awareness of ovarian cancer risk factors. There was a significant association between age and knowledge (p=0.047). Additionally, there was a significant association between higher education level and level of awareness of ovarian cancer risk factors (p=0.039). Conclusions: This study revealed that awareness of ovarian cancer risk factors among Malaysian women is low. The results show a need for improved public understanding about ovarian cancer risks and provision of important information for health professionals about initiatives needed for future awareness, prevention and screening programs.

• Journal of Haehwa Medicine
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• v.24 no.1
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• pp.25-36
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• 2015

Objective : This study aims to evaluate a risk of bias by Risk of Bias tool and RoBANS(Risk of Bias Assessment tool for Non-randomized Study) tool for clinical trial papers proving treatment effect of herbs to alopecia and provides the newest reason of effectiveness of herbs to alopecia. Methos : Data were collected through electronic database including NDSL, KISS, KMBASE, Koreantk, OASIS, KoreaMed, KISTI, Pubmd, Cochrane CENTRAL and CINAHL. Two experts in Oriental Medince assessed risk of bias of randomized controlled trials by Cochrane group's Risk of Bias tool and non-randomized controlled trials by RoBANS tool after searching, reviewing and selecting papers. Results : Total number of selected trials is 20 including 4 randomized controlled trials, 13 non-randomized controlled trials and 3 case reports. This study evaluates the risk of bias of 17 papers including 4 randomized controlled trials and 13 non-randomized controlled trials except 3 case reports by risk of bias tool and RoBANS tool. All papers of randomized controlled trials are evaluated unclear for random sequence generation and allocation concealment as there are no word on them. And all papers of non-randomized controlled trials are evaluated unclear for blinding of outcome assessments and relatively low for others. Conclusion : We must try to specify concretely methods of allocation concealment after planning and practicing it for reducing a selection bias in randomized controlled trials. Also report a reason of missing value and blinding outcome assessments. And we have to agonize and mention methods of blinding of researchers for reducing a detection bias in non-randomized controlled trials.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.503-510
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• 2016

The paper suggests to measure the risk of pedestrians inside urban railway stations. The level of risk is calculated in manner of both an average risk and average weighted risk of 9 different facility inside urban railway stations. Based on these level of risk, top 10 stations are chosen out of all the stations operated by Seoul Metro and Seoul Metropolitan Rapid Transit Cooperation (SMRT). In order to alleviate the level of risk, countermeasures for those risks are surveyed for 60 experts who are now involved in safety issues in those 2 railway operation companies. A countermeasure survey for the accidents is done into 2 ways. One is to lower the probability of making accidents and the other is to alleviate the consequence for accidents. The effectiveness of those alternatives is surveyed between 1 to 5 yardsticks and converted into one value for each alternative.

• Journal of Environmental Health Sciences
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• v.40 no.5
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• pp.397-406
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• 2014

Objectives: Perchloroethylene (PCE) is a volatile chemical widely used as a solvent in the dry-cleaning and textile processing industries. It was evaluated as Group 2 "probably carcinogenic to humans" by the Integrated Risk Information System (IRIS) of the United State Environmental Protection Agency (U.S. EPA) in 2012. In order to provide a scientific basis for establishing risk management measures for chemicals on the national priority substances list, aggregate risk assessment was conducted for PCE, included in the top-10 substances. Methods: We conducted the investigation and monitoring of PCE exposure (e.g., exposure scenario, detection levels, and exposure factors, etc.) and assessed its multi-media (e.g., outdoor air, indoor air, and ground water) exposure risk with a deterministic and probabilistic approach. Results: In human risk assessment (HRA), the level of human exposure was higher in the younger age group. The exposure level through inhalation at home was the highest among the exposure routes. Outdoor air or uptake of drinking water represented less than 1% of total contributions to PCE exposure. These findings suggested that the level of risk was negligible since the Hazard Index (HI) induced by HRA was below one among all age groups, with a maximum HI value of 0.17 when reasonable maximum exposure was applied. Conclusion: In conclusion, it was suggested that despite low exposure risk, further studies are needed considering main sources, including occupational exposure.

• Journal of Auto-vehicle Safety Association
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• v.5 no.1
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• pp.44-49
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• 2013

This paper presents a lateral collision risk index between an ego vehicle and a rear-side vehicle. The lateral collision risk is designed to represent a lateral collision risk and provide the appropriate threshold value of activation of the lateral collision management system such as the Blind Spot Detection(BSD). The lateral collision risk index is designed using the Time to Line Crossing(TLC) and the longitudinal collision index at the predicted TLC. TLC and the longitudinal collision index are calculated with the signals from the exterior sensor such as the radar equipped on the rear-side of a vehicle and a vision sensor which detects the distance and time to the lane departure. For the robust situation assessment, the perception of driving environment determining whether the road is straighten or curved should be determined. The relative motion estimation method has been proposed with the road information via the integrated estimator using the environment sensors and vehicle sensor. A lateral collision risk index was composed with the estimated relative motion considering the relative yaw angle. The performance of the proposed lateral collision risk index is investigated via computer simulations conducted using the vehicle dynamics software CARSIM and Matlab/Simulink.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.2761-2765
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• 2016

Opisthorchiasis is a health problem in rural communities of Thailand, particularly in the northeast and north regions. Therefore, this study aimed to investigate raw fish consuming behavior related to liver fluke infection among the population at risk for opisthorchiasis and cholangiocarcinoma (CCA). A cross-sectional descriptive study was conducted in Meuang Yang district, Nakhon Ratchasima province, northeast Thailand, between June and October 2015. Participants were screened for CCA, and samples who had a high score of CCA risk were purposively selected. A predesigned questionnaire was utilized to collect the data from all participants. $X^2-test$ was used for analysis of associations between demographic data and raw fish consumption. The results revealed that participants had past histories of stool examination (33.0%), liver fluke infection (21.0%), praziquantel use (24.0%), raw fish consumption (78.0%), relatives family consuming raw fish (73.0%), and relatives family with CCA (3.0%). Participants consumed several dished related to liver fluke infection, mainly raw fermented fish (13.0%), under smoked catfish (5.00%), raw pickled fish (4.00%), and raw spicy minced fish salad (3.00%). The most common types of cyprinoid fish were Barbodes gonionotus (39%), Hampala dispar (38%), Puntius brevis (37%), Cyclocheilichthys armatus (33%), Puntioplites proctozysron (32%), and Luciosoma bleekeri (30%), respectively. Participants had a low level of knowledge (mean=3.79, SD=0.74), moderate attitude (mean=7.31, SD=7.31) and practice (mean=38.64, SD=6.95) regarding liver fluke prevention and control. Demographic variables like age (>36 years old; $X^2-test=17.794$, p-value=0.001), education (primary school; $X^2-test=18.952$, p-value=0.001), marital status (married; $X^2-test=12.399$, p-value=0.002), and income (<5,000 baht; $X^2-test=27.757$, p-value=0.015) were significantly associated with raw fish consumption. This result indicates that the population had risk consumption for liver fluke infection particularly of various cyprinoid fishes that are $2^{nd}$ intermediate hosts. Therefore, health education is required to improve their behavior.

• The Journal of Engineering Geology
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• v.32 no.2
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• pp.221-239
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• 2022

Unknown geotechnical characteristics are key challenges in the design of piles for the plant, civil and building works. Although the N-values which were read through the standard penetration test are important, those N-values of the whole area are not likely acquired in common practice. In this study, the N-value is predicted by means of regression analysis with artificial intelligence (AI). Big data is important to improve learning performance of AI, so circular augmentation method is applied to build up the big data at the current study. The optimal model was chosen among applied AI algorithms, such as artificial neural network, decision tree and auto machine learning. To select optimal model among the above three AI algorithms is to minimize the margin of error. To evaluate the method, actual data and predicted data of six performed projects in Poland, Indonesia and Malaysia were compared. As a result of this study, the AI prediction of this method is proven to be reliable. Therefore, it is realized that the geotechnical characteristics of non-boring points were predictable and the optimal arrangement of structure could be achieved utilizing three dimensional N-value distribution map.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.5
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• pp.30-37
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• 2024

The valuation of infrastructure assets is typically conducted using the straight-line method, which employs the depreciated replacement cost as a basis. However, this approach has the limitation of failing to accurately reflect the actual value of the facility. In light of these considerations, the performance-based depreciation (PBD) method has been proposed as a means of evaluating the asset value of bridges on the basis of their performance, although it is not designed to take account of the environmental characteristics of individual bridges. This study proposes a hazard-performance based depreciation (HPBD) method that considers the risk level of individual bridges in the PBD method proposed in previous studies. The applicability of the proposed method was evaluated on more than 8,000 bridges. The risk factors for deterioration of bridges were selected, the hazard level of individual bridges was evaluated, and weights based on the hazard level were applied to the PBD method. The evaluation resulted in a present value comparable to that of the PBD method and a relatively high future value. It is postulated that the HPBD method, which considers the risk characteristics of individual bridges, can be used for a more reasonable evaluation and decision-making process.

• Journal of Preventive Medicine and Public Health
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• v.36 no.3
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• pp.230-238
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• 2003

Objectives : To estimate the value of statistical life (VSL) and health damage cost on theoretical mortality estimates due to environmental pollution. Methods : We assessed the health risk on three environmental problems and eight sub-problems. Willingness to pay (WTP) was elucidated from a questionnaire survey with dichotomous contingent valuation method and VSL (which is the division of WTP by the change of risk reduction) calculated from WTP. Damage costs were estimated by multiplying VSL by the theoretical mortality estimates. Results : VSLs from death caused by air pollution, indoor air pollution and drinking water contamination were about 0.3, 0.5 and 0.3 billion won, respectively. Damage costs of particulate matters ($PM_{10}$) and radon were higher in the sub-problems and were above 100 billion won. Because damage cost depends on theoretical mortality estimate and WTP, its uncertainty is reduced in the estimating process. Conclusion : Health damage cost or risk benefit should be considered as one scientific criterion for decision making in environmental policy.