• Geomechanics and Engineering
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• v.5 no.5
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• pp.485-497
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• 2013

The factor of safety is the most common measure of the safety margin for slopes. When the traditionally defined factor is used in kinematic approach of limit analysis, calculations can become elaborate, and iterative methods have to be used. To avoid this inconvenience, the safety factor was defined in terms of the work rates that are part of the work balance equation used in limit analysis. It was demonstrated for two simple slopes that the safety factors calculated according to the new definition fall close to those calculated using the traditional definition. Statistical analysis was carried out to find out whether, given normal distribution of the strength parameters, the distribution of the safety factor can be approximated with a well-defined probability density function. Knowing this function would make it convenient to calculate the probability of failure. The results indicated that the normal distribution could be used for low internal friction angle (up to about $16^{\circ}$) and the Johnson distribution could be used for larger angles ${\phi}$. The data limited to two simple slopes, however, does not allow assuming these distributions a priori for other slopes.

• Research in Community and Public Health Nursing
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• v.12 no.1
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• pp.239-246
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• 2001

This paper attempts to identify the occupational stress-related factors among the workers at the manufacturing industry and to provide the basic data concerning development of stress management program focused on the manufacturing industry. The subjects exhibit significantly highest level of 'the characteristics of task and participation in decision making factor'. And the mean score of 'the avoid coping strategies' was higher than 'the control coping strategies'. The main factor that affected the occupational stress responses was 'the physio-environmental factor' and it was explained 15.6% out of the total variance of the stress responses. Also, it would be explained 29% out of the total variance of the stress responses with 'the characteristics of task/participation in decision making factor', sex, social support, and 'extra-organizational stressor'. In conclusion. For developing the stress management program in workplace, 'the physical environmental factor' and 'the characteristics of task and participation in decision making factor' should be considered. Also, It should be identified the direct and indirect paths among factors that significantly related factors to the occupational stress of workers further more.

• Journal of Climate Change Research
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• v.9 no.1
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• pp.69-74
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• 2018

The purpose of this study is to suggest the methodology of $CO_2$ Emission Factor Verification and Quantitative Assessment in Ethylene Product Processes. At first, this study compare the IPCC (Intergovernmental Panel on Climate Change) 1996 Guideline and 2006 Guideline. And analyse methodology for estimating $CO_2$ emission and $CO_2$ emission factor in Ethylene product process. Also analyse cases of estimating $CO_2$ emission factor based on material balance. Methodology of $CO_2$ Emission Factor Verification and Quantitative Assessment are following the categories proposed by GIR (Greenhouse Gas Inventory and Research Center). There are total 12 factors in 8 categories and give 5 or 10 points according to their importance. Also this study suggests necessary data of document to meet the conditions. The result would help estimate accuracy Greenhouse Gas Inventory. Also contribute to establish policy on environmental assessment, air conservation, etc.

• Journal of environmental and Sanitary engineering
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• v.22 no.1 s.63
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• pp.67-74
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• 2007

The purpose of this study is to provide the necessarily basic data of the ideal growth of the students by investigating the effect of the student's stress due to the parent's achievement pressure. The sample of this study are In students consisting of 51 boys and 49 girls in the 3rd grade classes of "J" middle school located in Siheung city, Kyungki-do. The observed materials are used to investigate the parent's achievement pressure and the level of stress. Based on the observed data, the frequency, correlation, and t-test have been gained. The results are summarized as follows : 1. The perception of the parent's achievement pressure is shown more by the boy's achievement pressure($44.2{\pm}9.9$) than the girl's achievement pressure($39.939{\pm}11.089$), among the high level students. 2. The perception of the parent's achievement pressure is shown more the high($43.0{\pm}10.7$) and middle($42.9{\pm}11.8$) level students than the low($39.7{\pm}8.00$) level students. 3. The stress of male students was high in the Solving Problem stress factor with by the mean of $15.1{\pm}3.7$, and the stress of female students was high in the Self-Control stress factor with the mean of $13.3{\pm}3.9$. 4. The stress of high, middle, low level student was high in the Solution of Matter stress factor with the mean of $14.2{\pm}3.9$. 5. The results were the main cause of the stress than the parent's achievement pressure.

• Environmental Analysis Health and Toxicology
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• v.21 no.3 s.54
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• pp.229-238
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• 2006

Although, mercury (Hg) is not a naturally abundant element in the environment, residues frequently occur in many environmental compartments because of widespread contamination from industrial and agricultural practices. This research evaluated Hg-B concentrations of general population who was not occupationally exposed. And also evaluates the association between life factor and health effect with Hg-B concentration of general adult through interrelationship estimation and index about kidney function and oxidative damage that appeared by questionnaire survey and medical examination. Average concentration of Hg-B was 3.19 $\mu$g/L (ND$\sim$8.64 $\mu$g/L), and persons who exceed mercury exposure level (5 $\mu$g/L) presented in WHO (1990) appeared by 16 (7.0%). High-risk group (smoking and meat main intake group) had significantly higher Hg-B concentration than low-risk group (non-smoking and vegetable diet main intake group) (p < 0.05, low-risk group: 3.30 $\mu$g/L (ND$\sim$8.64 $\mu$g/L), high-risk group: 4.27 $\mu$g/L (ND$\sim$7.84 $\mu$g/L).

• Environmental Analysis Health and Toxicology
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• v.11 no.1_2
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• pp.1-10
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• 1996

A decrease in stratospheric ozone probably caused by chloroflurocarbons (CFCs) emissions, has been observed large parts of-the globe. It is generally accepted that if ozone levels in the stratosphere are depleted, greater amounts of shortwave ultraviolet radiationB (UVB) will reach the earth's surface, resulting in increased incidence of nonmelanoma skin cancer. In this study, we evaluated several mathematical models, such as a power and an exponential model, and a geometric model considering the surface area of a human body part and ages for the prediction of Skin cancer incidence caused by exposure to the UVB radiation. These models basically estimated the risk of skin cancer based on those measurements of the local ozone in stratosphere and UVB. Both were measured at a part of Seoul with a Dobson ozone spectrometer and Robertson-Berger UV Biometer for 1995. As a result, we calculated the point estimation applying a biological amplification factor (BAF), UVB radiation and other factors. We used a Monte-Carlo simulation technique with assumption on the distribution of each considered factor. The sensitivity analysis of model by there components conducted using Gaussian sensitivity method. The annual integral of UVB radiation was 2275 MED (minimal erythema dose)/yr. Also, an estimate of the annual amount of UVB reaching the earth's surface at a korea's latitude and altitude was 3328 MED/yr. The values of the radiation amplification factor (RAF) were ranged from 0.9 to 1.5 in Seoul. To give the effective factors required to model the prediction of skin cancer incidence caused by exposure to the UVB radiation in Korea, we studied the pros and cons of above mentioned models with the application of those parameters measured in Seoul, Korea.

• Journal of Soil and Groundwater Environment
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• v.18 no.5
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• pp.15-25
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• 2013

In this study, two kinds of soil-based proficiency testing materials (PTMs), NICE-012L and NICE-012R were prepared and certified for Benzen, Toluene, Etylbenzene and Xylene with evaluation of uncertainties. In order to analyse BTEX (Benzen Toluene Etylbenzene Xylene) for the candidate materials, GC/MS was used after pretreatment according to methods of soil analysis by Ministry of Environment. For the homogeneity test among bottles in terms of candidate materials, ISO 13528 and IUPAC Protocol were used and according to the result, both candidate materials showed sufficient homogeneity. Also, the stability test over the candidate materials was accessed according to the ISO Guide 35 by classifying short-term and long-term stability and the result showed that both candidate materials showed decent stability. The reference values of the two candidate materials depending on BTEX components were derived from the average of the 11 samples that were used for verification of the samples' homogeneity. Uncertainty of measurement was combined by uchar that was caused by a characteristic value, $u_{bb}$ that was caused by between-bottle homogeneity, and $u_{stab}$ that was caused by stability, and then combined uncertainty ($u_{PTM}$) was multiplied to the coverage factor (k) derived from the effective degree of freedom from each factor that leads to expanded uncertainty (U) in about 95% of confidence level. The proficiency testing materials developed through this study were supplied to National Institute of Environmental Research (NIER) and utilized as an external proficiency testing materials for evaluating analysis capacity of soil agencies with specialty in terms of soil analysis approved by Minister of Environment.

• Smart Structures and Systems
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• v.29 no.1
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• pp.41-51
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• 2022

Cables are critical components of cable-stayed bridges. A structural health monitoring system provides real-time cable tension recording for cable health monitoring. However, the measurement data involve multiple sources of variability, i.e., varying environmental and operational factors, which increase the complexity of cable condition monitoring. In this study, a one-class classification method is developed for cable condition assessment using Bayesian factor analysis (FA). The single-peaked vehicle-induced cable tension is assumed to be relevant to vehicle positions and weights. The Bayesian FA is adopted to establish the correlation model between cable tensions and vehicles. Vehicle weights are assumed to be latent variables and the influences of different transverse positions are quantified by coefficient parameters. The Bayesian theorem is employed to estimate the parameters and variables automatically, and the damage index is defined on the basis of the well-trained model. The proposed method is applied to one cable-stayed bridge for cable damage detection. Significant deviations of the damage indices of Cable SJS11 were observed, indicating a damaged condition in 2011. This study develops a novel method to evaluate the health condition of individual cable using the FA in the Bayesian framework. Only vehicle-induced cable tensions are used and there is no need to monitor the vehicles. The entire process, including the data pre-processing, model training and damage index calculation of one cable, takes only 35 s, which is highly efficient.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.5
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• pp.967-976
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• 2018

The purpose of this study is to examine the effects of individual and environmental factors on the career identity of Chinese-Korean adolescents in Yanbian, China. Academic achievement and self-esteem were considered as individual factors, and parent attachment and teacher attachment were considered as environmental factors. This study sought to answer the question "Which individual and environmental factors had an effect on the career identity of Chinese-Korean adolescents in Yanbian, China?" The data was collected from 290 middle school students in Yanbian, China through the use of a survey. The results were as follows: self-esteem as an individual factor and teacher attachment as an environmental factor were found to have a significant effect on career identity. Also, teacher attachment as an environmental factor had the greatest effect on career identity. In the conclusion, we considered theoretical and practical implications of this study to improve the career identity of Chinese-Korean adolescents in China.

• Analytical Science and Technology
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• v.19 no.6
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• pp.544-552
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• 2006

Emission tests were carried out to investigate the characteristics of concentration according to flooring sort using small chamber method. The target Volatile Organic Compounds (VOC) included 27 individual compounds of environmental concern, which were determined by adsorption sampling and thermal desorption coupled with GC/MS method and by DNPH cartridge/HPLC method. The emission factor of Total Volatile Organic Compounds (TVOC) and Formaldehyde (HCHO) was detected $0.3mg/m^2{\cdot}h$ and $0.2mg/m^2{\cdot}h$ respectively, and the floorings of 37 (9 PVC Tile, 10 PVC Sheet, 18 Flooring) were satisfied emission standard. TVOC emission factor appeared in order of concentration of PVC Sheet, PVC Tile, and floor flooring, while HCHO was detected very high emission factor (as $0.4mg/m^2{\cdot}h$) at floor flooring above PVC series (as $0.001mg/m^2{\cdot}h$).