• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.5
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• pp.68-75
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• 2021

This study performed simulating water absorption in various pre-cracked concretes. 2D-Finite Element Analysis (2D-FEA) model was developed based on experimental results on the amount of absorbed water in concrete with the exposure time. Results from the 2D-FEA showed that both crack width and crack depth strongly affect the amount of absorbed water in cracked concrete. In addition, water absorption rate is introduced and a predictive equation is suggested to estimate the rate in order to quantify the amount of absorbed water in cracked concrete. It was confirmed that water absorption in concrete having less than 150 mm crack depth was dominated as a main transport factor regardless of crack width. Therefore, considering that steel corrosion caused by chlorides dissolved in water mainly occurs in reinforced concrete structures, it is necessary that crack depth as well as crack width should be investigated in reinforced concrete structures at the time of field-inspection.

• The Journal of Korean Society for School & Community Health Education
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• v.13 no.3
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• pp.73-86
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• 2012

Objectives: This study was conducted to explore the effect of the sexuality education in elementary school in regard to students' knowledge, attitude, and role identity about sex. Methods: We classified students into experimental group and control group, and carries out the planned sexuality education to the experimental group. Study subjects were 200 students in one elementary school. Experimental group compromised of 50 boys and 50 girls, and control group so did. Self-administered questionnaire was used for preliminary investigation from 15th to 16th, October in 2009. The post investigation was carried out to the control group 5 weeks later, and to the experimental group for 5 weeks (total 10 hours, 2hours each a week) after the sexuality education from 23th of November to 25th of November, 2009. Results: Experimental group had significantly higher post-inspection scores of sex-related knowledge, attitude against sex, sex-related role identity (excluding leadership dominance, concession, cheerfulness gentleness and sympathy shyness) than pre-inspection scores. Conversely, control group had insignificantly higher post-inspection scores (excluding all scores of sex-related knowledge and scores of atttitude against sex including psychological development and pregnancy). Conclusions: Our study suggested that sexuality education in elementary school have an impact on forming knowledge, attitude, and role identity regarding the sex.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4313-4318
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• 2016

Background: This study documented the performance of providers of visual inspection with acetic acid (VIA) at primary health centers, assessing their compliance with the VIA skills checklist and determinants of non-compliance, and exploring their perceptions of VIA training sessions. Materials and Methods: A cross-sectional study was conducted among VIA providers in the $Mekn\grave{e}s$-Tafilalet region of Morocco. Structured observation of their performance was conducted through supervisory visits and multiple focus group discussions (FGDs). Results: Performance of all the recommended steps for effective communication was observed in a low proportion of procedures (36.4%). Midwives/nurses had higher compliance than general practitioners (GPs) (p<0.001). All recommended steps for VIA examination were performed for a high proportion of procedures (82.5%). Compliance was higher among midwives/nurses than among GPs (p<0.001) and among providers in rural areas than those in urban areas (p<0.001). For pre-VIA counselling, all recommended steps were performed for only 36.8% of procedures. For post-VIA counseling, all recommended steps were performed in a high proportion (85.5% for VIA-negative and 85.1% for VIA-positive women). Midwives/nurses had higher compliance than GPs when advising VIA-positive women (p=0.009). All infection prevention practices were followed for only 14.2% of procedures, and compliance was higher among providers in rural areas than those in urban areas (p<0.001). Most FGD participants were satisfied with the content of VIA training sessions. However, they suggested periodic refresher training and supportive supervision. Conclusions: Quality assurance of a cervical cancer screening program is a key element to ensure that the providers perform VIA correctly and confidently.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.121-125
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• 2018

This paper presents the assessment of 7-wire strand monitoring using acoustic emission technique for bridges. 7-wire strand is widely used construction materials to provide additional tensile force to bridges. PSC (PreStressed Concrete) bridge and cable-stayed bridge are representatives for such cases. However, as the bridge aging progresses recently, corrosion problems of strand are emerging. For this reason, various NDT (Non-Destructive Test) methods for cable inspection are being studied and applied to the field. One of the NDT methods, acoustic emission technique, is known as an effective technique to detect cable damage and breakage. In this study, to evaluate the applicability of acoustic emission technique to bridges, acoustic emission signals according to damage of the strand were acquired and analyzed by tensile test. Moreover, The optimal AE sensor type was selected for field application. As a result, it is considered that the acoustic emission technique will be able to detect corrosion breakage and signs of rupture.

• Journal of the Society of Disaster Information
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• v.14 no.3
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• pp.280-287
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• 2018

Purpose: The study is based on comparative review of the actual inspection of apartments and aims at proposing easy accessible and useful safety control which is enhanced from pre-existing safety apparatus. Method: On the basis of preceding research data of apartment buildings, the study presents reported problems and real condition of apartment buildings based on Housing Related Legislation and Housing Act. Results: Safety management plans and safety inspection for buildings are needed. When conducting a safety check, traceability management system for internal/exterior facilities should be available. Most important of all, 24 hour a day of self-management system for elevators, fire protection, and security cameras is necessary. Conclusion: Through the study, there should be a process of confirming problems of building security management; such as checking the management condition through apartments' resident representatives, and seeking improvement measures.

• Journal of the Korean Society of Safety
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• v.36 no.3
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• pp.31-39
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• 2021

In Korea, more than half of work-related fatalities have occurred on construction sites. To reduce such occupational accidents, safety inspection by government agencies is essential in construction sites that present a high risk of serious accidents. To address this issue, this study developed risk prediction models of serious accidents in construction sites using five machine learning methods: support vector machine, random forest, XGBoost, LightGBM, and AutoML. To this end, 15 proactive information (e.g., number of stories and period of construction) that are usually available prior to construction were considered and two over-sampling techniques (SMOTE and ADASYN) were used to address the problem of class-imbalanced data. The results showed that all machine learning methods achieved 0.876~0.941 in the F1-score with the adoption of over-sampling techniques. LightGBM with ADASYN yielded the best prediction performance in both the F1-score (0.941) and the area under the ROC curve (0.941). The prediction models revealed four major features: number of stories, period of construction, excavation depth, and height. The prediction models developed in this study can be useful both for government agencies in prioritizing construction sites for safety inspection and for construction companies in establishing pre-construction preventive measures.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.4
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• pp.327-338
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• 2014

The objective of this study is to enhance the effectiveness of Korean Inspection and Maintenance (I/M) program. Three main tasks are: to measure pollutant emissions of in-use light-duty diesel vehicles (LDVs); to evaluate the validity of existing smoke control scheme for low-smoke-emitting vehicles, which have diesel particulate filters, DPF, to meet stringent Euro-5 emission limits; and to assess the necessity and the benefit of $NO_x$ inspection, which is not involved in current I/M program. We measured second-by-second smoke, particulate and gaseous emissions of 27 LDVs using opacity smoke meter, photo-acoustic soot sensor, and portable emissions measurement system, respectively, under the Korean I/M test driving cycle, KD-147. We find that the DPF plays a key role in controlling soot, which can be considered as black carbon contained in particulate matter. Thus, from an I/M perspective, we believe smoke inspection strategies for Euro-5 diesel vehicles should be more focused on the capability of detecting DPF malfunctions or failures, in order to keep DPF properly functional. Fleet averaged distance-specific $NO_x$ emissions are consistently higher than corresponding emission limits, and the values are similar among pre-Euro-3, Euro-3, and Euro-4 vehicle fleets. These findings indicate that the $NO_x$ inspection should be incorporated into current I/M program in order to manage urban $NO_x$ emissions. This research allows the Korean I/M program keep pace with developments in vehicle technologies, as well as the increased emphasis on $NO_x$ with respect to air quality and human health.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.2
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• pp.261-274
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• 2014

The purpose of this study was to examine the effects of food safety management support in the Center for Children's Foodservice Management (CCFSM) on foodservice facilities for children in Busan area. We assessed the status of hygiene and safety practices of institutional and non-institutional foodservice on a quarterly basis by using an inspection checklist for food hygiene and safety developed by dieticians from February to December in 2013. The subjects were 103 children's foodservices, including 37 institutional and 66 non-institutional foodservices. Inspection checklist consisted of nine categories with 39 checklists; general characteristics, personal hygiene, ingredient control, menu planning, cooking processing control, serving management, washing, disinfection and storage control, and environment and safety management. The average score of each field (pre-supporting/post-supporting) in institutional foodservice was 0.56/0.92 for personal hygiene, 0.55/0.87 for ingredient control, 0.76/0.97 for menu planning, 0.53/0.89 for processing control, 0.27/0.67 for serving management, 0.47/0.91 for washing, disinfection and storage control, and 0.61/0.91 for environment management and 0.64/0.94 for safety management. In non-institutional foodservice, the average score of each field (pre-supporting/post-supporting) was 0.49/0.80 for personal hygiene, 0.52/0.75 for ingredient control, 0.78/0.97 for menu planning, 0.42/0.76 for processing control, 0.32/0.61 for serving management, 0.57/0.88 for washing, disinfection and storage control, and 0.46/0.82 for environment management and 0.73/0.88 for safety management. The average scores of all categories (pre-supporting/post-supporting) were 0.57/0.91 in institutional foodservice and 0.53/0.82 in non-institutional foodservice. The effects of management support in CCFSM on institutional foodservice were higher than those of non-institutional foodservice. Based on these results, we found that management support in CCFSM on foodservice facilities for children had a significantly positive effect on status of hygiene and safety practice regardless of foodservice facility size.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.2
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• pp.110-116
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• 2013

A concrete structure has become bigger and higher because of development of construction technology and a change in construction environment. Also it tends to focus on repairing, reinforcement and exterior in harmony with environment for structure maintenance and performance improvement. The research is about eco friendly durable painting applicable to concrete structure using civil and architecture. it purpose to improve external beauties and durable problems due to flexibility by variation of temperature, adhesion of exterior wall, crack and delamination in existing organic and mineral painting. For those problems, we made a eco friendly pre-paint that is made with preliminary treatment mixture as a highly enriched waterproof agent and adhesive increasing agent in preprocessing mixture. Then we performed an experiment on durability of prevention neutralization of concrete, durability abrasion, hiding power, adhesion, temperature resistance and resistance to chemical attack. The result of an experiment shows that hiding power is over 0.96 in standard test, durability abrasion test got higher value 1mg than water paint 75mg and tensile strength is 6 times higher than standard waterproof specification.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.2
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• pp.9-17
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• 2022

To take into account of the increasing speed of next generation high-speed trains, a new design code for the traffic safety of railway bridges is required. To solve dynamic responses of the bridge, this research offers a numerical analyses of PSC (Pre-stressed Concrete) box girder bridge, which is most representative of all the bridges on Gyungbu high-speed train line. This model takes into account of the inertial mass forces by the 38-degree-of-freedom and interaction forces as well as track irregularities. Our numerical analyses analyze the maximum vertical deflection and DAF (Dynamic Amplification Factor) between simple span and two-span continuous bridges to show the dynamic stability of the bridge. The third-order polynomial regression equations we use predict the maximum vertical deflections depending on varying running speeds of the train. We also compare the vertical deflections at several cross-sectional positions to check the influence of running speeds and the maximum irregularity at a longitudinal level. Moreover, our model analyzes the influence lines of vertical deflection accelerations of the bridge to evaluate traffic safety.