• Journal of the Korean Society of Safety
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• v.31 no.3
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• pp.89-95
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• 2016

Lately, the high-strength concrete is often used to increase the lifespan of bridges. The benefits of using the high-strength concrete are that it increases the durability and strength. On the contrary, it reduces the cross-section of the bridges. This study conducted structural performance tests of the bridge deck slabs applying high-strength concrete. As result of the tests, specimens of bridge deck slabs were destroyed through punching shear. Moreover, the tests exposed that the high-strength concrete bridge deck slabs satisfy the flexural strength and the punching shear strength at ultimate limit state(ULS). Also, limiting deflection of the concrete fulfilled serviceability limit state(SLS) criteria. These results indicated that the bridge deck slabs designed by high-strength concrete were enough to secure the safety factor despite of its low thickness.

• Safety and Health at Work
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• v.7 no.2
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• pp.120-123
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• 2016

Background: To assess in a laboratory setting the ability to stay awake in a sample of workers of an Italian hospital and to investigate the association between that ability and the risk of occupational injury. Methods: Nine workers at the University Hospital of Udine who reported an occupational injury in the study period (cases), and seven noninjured workers (controls) underwent a polysomnography and four 40-minute maintenance of wakefulness tests (MWT). Differences in sleep characteristics and in wakefulness maintenance were assessed using Wilcoxon's rank sums tests and Fisher's exact tests. Results: Controls had greater sleep latency, lower total sleep time, fewer leg movements, and a higher percentage ratio of cycling alternating pattern, were more likely not to fall asleep during the MWT and were less likely to have two or more sleep onsets. Although not all the differences reached statistical significance, cases had lower sleep onset times in Trials 1-3. Conclusion: In the literature, the evidence of an association between MWT results and real life risk of accidents is weak. Our results suggest a relationship between the MWT results and the risk of injury among hospital workers.

• Safety and Health at Work
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• v.10 no.3
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• pp.314-320
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• 2019

Background: Sitting posture may be related to risk factors, including inadequate weight-bearing support, particularly when maintained for long periods. Considering that body weight is loaded in a closed support system composed of the seat, backrest, floor and working surface, the aims of the present study were to describe the development of an ergonomic sitting workstation to continuously record weight-bearing at the seat, chair, backrest, work surface, and floor and to test its measurement properties: reproducibility, criterion-related validity, and sensitivity. Methods: Rigid bodies (1 to 30 kg) and participant weights were recorded to evaluate the workstation measurement properties. Results: Rigid body tests showed variation values less than 0.050 kg on reproducibility test and errors below 5% of measured value on criterion validity tests. Participant tests showed no statistically significant differences between repeated measures ($p{\geq}0.40$), errors were less than 2% of participant weights an sensitivity presented statistically significant changes (p = 0.007). Conclusion: The sitting workstation proposed showed to be reliable, valid and sensitive for use in future ergonomic studies to evaluate the sitting posture.

• Structural Engineering and Mechanics
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• v.82 no.5
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• pp.557-569
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• 2022

The retrofit of existing structures in high seismic zones is a crucial issue in the earthquake engineering field. The interest of the research community is particularly high for the structures that do not respect current seismic codes and present structural deficiencies such as poor detailing and lack of capacity design provisions. A reinforced concrete (RC) school building is used as case study to show the influence of different knowledge levels on the seismic retrofitting cost assessment. The safety assessment of the case study building highlights deficiencies under both vertical and seismic loads. By considering all the possible knowledge levels defined by the Italian such as by the European codes in order to derive the mechanical properties of the school building constitutive materials, the retrofit operations are designed to achieve different seismic safety thresholds. The retrofit structural costs are calculated and summed up to the costs for in-situ in tests. The paper shows how for the case study building the major costs spent for a large number of in-situ tests allows to save a consistent amount of money for retrofit operations. The hypothesis of demolition and reconstruction of the building is also compared in terms of costs with all the analyzed retrofit options.

• Journal of Industrial Technology
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• v.43 no.1
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• pp.7-13
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• 2023

Nowadays, traffic congestion is emerging as a major problem due to the rapid population growth and the increase in automobiles. The train is a convenient means of transportation that can efficiently solve these problems. Trains have been developed in line with human aspirations for a long time, but research on safety is still insufficient. This study aims to check safety by conducting static tests and fatigue tests on bogie frames, and to help develop bogie frames in the future. For the static test, a strain gauge was attached to the point where the local stress concentration was expected beforehand, and the result value was derived, compared with existing theories, and expressed as a Goodman diagram. In the fatigue test, a total of 10 million loads were applied over three stages, and no cracks appeared in the non-destructive test conducted after each stage. Both tests were conducted according to the strict test method of the bogie frame presented by the UIC Code. It satisfied both fatigue life and strength evaluation criteria and was judged to be a bogie frame usable for safe train production.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.33-39
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• 2004

A ship runs with various modes of motion due to waves. Among the modes, roll mainly influences on the safety of cargos and crew's fatigue. Therefore a ship equipped with anti-rolling devices are on an increasing trend. In this research, we developed a free running model ship to evaluate the performances of fin stabilizer and moving weight stabilizer. Also those performance tests were carried out through the proposed test procedure.

• Nuclear Engineering and Technology
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• v.41 no.3
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• pp.307-318
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• 2009

KAERI (Korea Atomic Energy Research Institute) has developed the GAMMA+ code for a thermo-fluid and safety analysis of a VHTR (Very High Temperature Gas-Cooled Reactor). A key safety issue of the VHTR design is to demonstrate its inherent safety features for an automatic reactor power trip and power stabilization during an anticipated transient without scram (ATWS) accident such as a loss of forced cooling by a trip of the helium circulator (LOFC) or a reactivity insertion by a control rod withdrawal (CRW). This paper intends to show the ATWS assessment capability of the GAMMA+ code which can simulate the reactor power response by solving the point-kinetic equations with six-group delayed neutrons, by considering the reactivity changes due to the effects of a core temperature variation, xenon transients, and reactivity insertions. The present benchmark calculations are performed by using the safety demonstration experiments of the 10 MW high temperature gas cooled-test module (HTR-10) in China. The calculation results of the power response transients and the solid core temperature behavior are compared with the experimental data of a LOFC ATWS test and two CRW ATWS tests by using a 1mk-control rod and a 5mk-control rod, respectively. The GAMMA+ code predicts the power response transients very well for the LOFC and CRW ATWS tests in HTR-10.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.24 no.1
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• pp.14-22
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• 2017

Purpose: To study aimed to examine the impact of the Nursing and Care=giving Integrated Service on nursing work performance, nurse' job satisfaction, and patient safety. Methods: A total of 66 nurses were selected as participants, comprising 30 nurses working in Nursing and Care=giving Integrated Service hospital ward, and 33 nurses working in a general hospital ward with a similar patient and disease group and distributed moderately. For data analysis, t-tests, ANOVA, and $X^2$ tests were conducted. Results: Nursing work performance in the Nursing and Care=giving Integrated Service ward was higher than that in the general hospital ward, but this difference was not statistically significant. Conversely, job satisfaction was lower among nurses in the Nursing and Care=giving Integrated Service ward, although again the difference was not significant. However, the Nursing and Care=giving Integrated Service ward had a significantly lower rate of safety-related accidents in patients compared to the general hospital ward. Conclusion: In order to expand and improve patient safety and other aspects of the Nursing and Care=giving Integrated Service, there is a need to establish a mediation strategy for increasing nurses' work performance and job satisfaction.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.3
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• pp.401-417
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• 2011

The purpose of this study was to investigate consumer concerns about hazardous elements on foods and recognition of the roles of government, food producers, and consumers in securing food safety. The data were collected from the 443 adult consumers living in Seoul, Busan, Daegu, Incheon, Kwangju and Daejeon through a self-administered questionnaire. Frequencies, t tests, analysis of variance and Duncan's multiple range tests were conducted using SPSS Windows. The results of the survey were as follows: (1) the respondents were worried about health risks related to hazardous elements on foods, (2) many respondents were more worried about preservatives of imported foods than those of domestic foods, and (3) most respondents mentioned that observance of enforcement regulations by producers was the most important factor for ensuring food safety in the future. These results imply that regulations regarding the safety of imported foods should be increased.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.2
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• pp.305-314
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• 2012

This study examined awareness and information acquisition behavior regarding food hygiene and safety and information search behavior of college students. The sample was obtained from 284 students in Yeungnam region through a self-administered questionnaire. To describe characteristics of the respondents, frequency distributions were used. In addition, $t$ tests, analysis of variance and Duncan multiple range tests were conducted. Data were analyzed by SPSS Windows V.18.0. The results of the study were as follows: (1) most respondents were concerned about food hygiene and safety. They were mostly interested in the expiration date label on breads, milk/dairy products, fish products and meat products, and price of cookies. Many respondents answered that foods produced and distributed in Korea were not safe. The respondents were most worried about endocrine disruptors among various food risk factors. The respondents received information on food hygiene and safety from blogs, mini-homepages, or Kin-searches on the Internet, electronic media, and food labeling in decreasing order.