• Journal of the Korean Institute of Gas
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• v.18 no.4
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• pp.68-75
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• 2014

It is necessary to control and evaluate human factors to reduce economic loss by major accident in toxic gas facilities. Conventional works to evaluate hazards have been focused on mechanical and systematic failure, while only a little works have been studied on managing human errors. In this work, a classification system of performance shaping factor (PSF) was suggested to consist human error in managing accident in the toxic gas facilities. Four types of PSFs (human, system, task characteristics, and task environment) were collected, reviewed, and analyzed to be categorized selected according their characteristics of situational, task, and environmental parameters. The PSFs were further modified to set up PSF systems adequate to evaluate human error, and the proposed system to consist PSFs to evaluate human error was further studied through accident analysis in toxic gas facilities.

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.2
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• pp.115-131
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• 2011

Recently, considering the aspects of disaster prevention and environmental damage, the construction of a twin tunnel is increasing. When constructing a twin tunnel, the stresses are concentrated at the pillar so that stability of the tunnel is decreased. Since the previous studies on the behavior of a twin tunnel pillar are mainly restricted to the estimation of the tunnel behavior and the analysis of surface settlement, there is a limit to a quantitative stability estimation of the pillar. Therefore, it was quantitatively investigated how the pillar width of a twin tunnel affects its stability. To ensure this end, global tunnel safety factors obtained numerically using shear strength reduction technique, local safety factors of a pillar using the equation that Matsuda et al. suggested, and strength/stress ratios of the pillar were estimated and their results were analyzed for two sections with different rock covers. For a reasonable design of a twin tunnel pillar, it was turned out that strength/stress ratio, the local pillar safety factor, and global tunnel safety factor should be used interrelatedly rather than independently.

• Journal of the Korean Society for Library and Information Science
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• v.49 no.3
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• pp.253-272
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• 2015

This study analyzed library awareness and anxiety among people in their 20s living in East Asia. The objective is to develop the international library cooperation agenda for life-long education proliferation. User groups in Korea, China, and Japan were investigated to understand the differences in library awareness based on the situational contexts such as preferred resources, use frequency, educational level, and gender. Results of the data analysis showed the correlation between library anxiety and use patterns such as preferred information sources and frequency of use. Specifically, the user group in China has the highest level of library anxiety with every factor. Also, the Korean user group was measured to have the lowest level of library anxiety in terms of digital information factor. Based on these results, the study presents several recommendations for resolving library anxiety such as embracing new information need with regard to environmental change and suggesting a new space policy for libraries.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.1
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• pp.27-34
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• 2013

Background subtraction is one of the key techniques for automatic video content analysis, especially in the tasks of visual detection and tracking of moving object. In this paper, we present a new sample-based technique for background extraction that provides background image as well as background model. To handle both high-frequency and low-frequency events at the same time, multiple interval background models are adopted. The main innovation concerns the use of a confidence factor to select the best model from the multiple interval background models. To our knowledge, it is the first time that a confidence factor is used for merging several background models in the field of background extraction. Experimental results revealed that our approach based on multiple interval sampling works well in complicated situations containing various speed moving objects with environmental changes.

• Structural Engineering and Mechanics
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• v.74 no.3
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• pp.351-363
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• 2020

Based on the dynamic tests of recycled aggregate concrete (RAC) short columns confined by the hoop reinforcement, the dynamic failure mechanism and the mechanical parameters related to the constitutive relation of confined recycled aggregate concrete (CRAC) were investigated thoroughly. The fracturing sections were relatively flat and smooth at higher strain rates rather than those at a quasi-static strain rate. With the increasing stirrup volume ratio, the crack mode is transited from splitting crack to slipping crack constrained with large transverse confinement. The compressive peak stress, peak strain, and ultimate strain increase with the increase of stirrup volume ratio, as well as the increasing strain rate. The dynamic confining increase factors of the compressive peak stress, peak strain, and ultimate strain increase by about 33%, 39%, and 103% when the volume ratio of hoop reinforcement is increased from 0 to 2%, but decrease by about 3.7%, 4.2%, and 9.1% when the stirrup spacing is increased from 20mm to 60mm, respectively. This sentence is rephrased as follows: When the stirrup volume ratios are up to 0.675%, and 2%, the contributions of the hoop confinement effect to the dynamic confining increase factors of the compressive peak strain and the compressive peak stress are greater than those of the strain rate effect, respectively. The dynamic confining increase factor (DCIF) models of the compressive peak stress, peak strain, and ultimate strain of CRAC are proposed in the paper. Through the confinement of the hoop reinforcement, the ductility of RAC, which is generally slightly lower than that of NAC, is significantly improved.

• Safety and Health at Work
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• v.12 no.3
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• pp.339-345
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• 2021

Background: Some researchers state that they are not yet able to provide a deep understanding of the underlying causes of unsafe behaviors (UBs). Therefore, the present study was conducted to investigate the attitudes and experiences of Iranian workers of UBs. Methods: This present study was conducted in 35 industries using a semistructured interview based on grounded theory. Forty participants were interviewed, including 13 industrial safety and health experts and 27 workers and supervisors. The analysis of the present study consisted of a three-step coding process including open, axial, and selective coding. Results: The results showed that the factors affecting UBs could be classified into three categories: organizational, individual, and socioeconomic factors. Organizational factors were divided into 6 parts: procedure and environmental conditions, communications, monitoring, organizational safety culture, resource allocation, and human resources. Socioeconomic factors had three subcategories: community safety culture, type of organizational ownership, and economic problems. Finally, the individual factors were classified into two categories of personality traits and individual competence. Conclusion: The results showed that organizational factors were the most categorized, and it is estimated that this factor has a more important role in the UBs. Of course, to better understand the close relationship between these factors and find the weight and importance of each factor, it needs to measure it with multicriteria decision systems.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.4
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• pp.365-373
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• 2018

Objective: This study aims to analyze the relationship between employment status and the prevalence of chronic obstructive pulmonary disease (COPD) for manufacturing and construction workers. Methods: Subjects, who had or have worked as temporary workers in manufacturing or construction worksites for the longest career years, were extracted from the KNHANES(2007-2009) database. Characteristics of demographical, socio-economic, and smoking history were treated as independent variables. Considering that smoking experience and age are significantly influential in the prevalence of COPD, logistic regressions were analyzed after stratifying subjects according to their smoking experience and age. A two-stage stratified systematic sampling method was applied for the logistic regression analysis. Results: Age, gender, and household income level were associated with the prevalence of COPD in both smoking and non-smoking groups. However, employment status was only significant among smoking group. Smoking experience and age were significantly related to the prevalence of COPD among all age groups. In addition, employment status and household income level were also associated with the prevalence of COPD in young aged group. But gender was the only significant factor among the elder group. Conclusions: This study confirmed that employment status was a major social factor which may be related to the prevalence of COPD. Proper supports such as providing safety measures should be provided to temporary workers to manage their respiratory health.

• Environmental and Resource Economics Review
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• v.30 no.2
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• pp.347-364
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• 2021

Carbon neutral policy in Korea pays limited attention to the concept of sustainable economic growth. This limitation can be compared with other countries' carbon neutral policies such as US, UK and China where the climate change policies are closely connected to economic policies to boost further economic growth. This paper adopts a Ramsey growth model to account for the impact of carbon neutral policy on long-term economic growth and the accumulation capital. The model incorporates the Hartwick rule to allow sustainability of economic growth by transforming resource input into other input factor for growth. The analysis provides a possibility of low accumulation of capital as a result of carbon neutral policy in the absence of effective transformation of fossil-fuel factor into growth-related productive capital. Such low capital stock can be more aggravated when there exists a rent-seeking behavior of various interest groups with voracity to exploit social capital.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.4
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• pp.367-373
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• 2022

We analyzed work safety risk factors, which are likely to occur during fishing in gillnet fishing vessels using the written verdict of the Korea Maritime Safety Tribunal from 2016 to 2020, and considered work safety management. Of the total of 37 fatal accidents, three cases in the East Sea, six cases in the South Sea, and 28 cases in the West Sea were very frequent. The accident rate per vessel by sea area (%) was 0.08% in East Sea, 0.12% in South Sea, and 0.40% in the West Sea. Based on the East Sea, the number of fatal accidents was 1.6 times higher in the South Sea and 5.4 times higher in the West Sea. Six cases (16.2%) occurred during departure and preparation for fishing in the fishing process, and all other 31 cases (83.8%) occurred during fishing operation. In the order of accident types, 21 cases (56.8%) of being struck by object, eight cases (21.6%) of contact with machinery and six cases (16.2%) of falls from height were found to be fatal accidents in gillnet fishery. Human factors, such as fishers' carelessness and negligent safety management by captain accounted for 27 cases (73.0%) of the main cause, and 35 cases (94.6%) of the secondary cause. In addition to human factors such as fisher's carelessness and negligent safety management by captain, mechanical factors, environmental factors and management factors must be improved together to reduce human casualties. These results are expected to be utilized as basic data for reducing safety accidents during the work of fishers.

• Journal of the Korean Geotechnical Society
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• v.26 no.10
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• pp.49-60
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• 2010

Unsaturated permeability function is an important factor in the design and analysis of various unsaturated soil structures. Generally the permeability characteristics decrease as the mat ric suction increases and the trend is similar to water retention characteristics of a soil. The permeability of unsaturated soils can be obtained directly by laboratory tests or indirectly by estimation methods from other soil properties. For unsaturated soils sampled from 7 areas in KOREA, SWCCs and unsaturated permeability functions were obtained by experimental tests. The unsaturated permeability results were also compared with the unsaturated permeability functions derived from the SWCCs theoretically. However, the current estimation models of unsaturated permeability function did not express the unsaturated permeability characteristics. Therefore, the FXK-M permeability function was modified to predict more accurate permeability functions for Korean weathered soils using a correction factor that can be calculated from the air-entry value of SWCC. The new estimation model resulted in good agreements for all tested soils.