• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.884-891
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• 2020

The collapse of bridges can cause massive casualties and economic losses. Therefore, it is thus essential to evaluate the structural safety of bridges. For this task, structural reliability analysis, considering various bridge-related uncertainty factors, is often used. This paper proposes a new computational platform to perform structural reliability analysis for bridges and evaluate their structural safety under various loading conditions. For this purpose, a software package of reliability analysis, Finite Element Reliability Using MATLAB (FERUM), was integrated with MIDAS/CIVIL, which is a widely-used commercial software package specialized for bridges. Furthermore, a graphical user interface (GUI) control module has been added to FERUM to overcome the limitations of software operation. In this study, the proposed platform was applied to a simple frame structure, and the analysis results of the FORM (First-Order Reliability Method) and MCS (Monte Carlo simulation), which are representative reliability analysis methods, were compared. The proposed platform was verified by confirming that the calculated failure probability difference was less than 5%. In addition, the structural safety of a pre-stressed concrete (PSC) bridge was evaluated considering the KL-510 vehicle model. The proposed new structural reliability analysis platform is expected to enable an effective reliability-based safety evaluation of bridges.

• Journal of Navigation and Port Research
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• v.28 no.5
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• pp.395-403
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• 2004

The prevention of marine accidents has been a major topic in marine society and various policies and countermeasures have been developed, applied to the industries. The coastal VTS and navigational aids are considered as one of the effective methods to promote marine safety but they need relatively huge amount of budgets to build Thus prior to establishing these coastal VTS and navigational aids, it should be evaluated the navigational safety level in the coastal waterways from the Environmental Stress. So far as human beings are concerned, there are many types of fuzziness in the evaluation of navigational safety level. In order to reflect these fuzziness on this evaluation, this paper introduces the fuzzy integral suggested by Choquet to represent the fuzziness in the evaluation process. This paper aims to develop the method for this evaluation from the viewpoint of mariner's operational stress using the fuzzy measure and Choquet integral. In this paper, Korean coastal area is divided into 8 sectors and evaluated the priority for the needs of coastal VTS and navigational aids.

• Journal of Food Hygiene and Safety
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• v.17 no.3
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• pp.124-128
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• 2002

The effect of different ethanol feeding protocols on the oxidative stress in liver and blain of rats was studied. The rats were fed 5%-ethanol solution in drinking water (5%-EtOH group) or 2.5g ethanol/kg body wt. once daily intragastrically (2.5g-EtOH group). The levels of thiobarbituric acid reactive substances (TRARS) and vitamin EI in the liver, cerebrum and cerebellum were measured. In the liver of 5%-EtOH group, the level of TBARS was not changed, whereas vitamin I was significantly increased compared to control group. In the liver of 2.5g-EtOH group, the level of TBARS was significantly increased compared to control group and the vitamin E concentration was not affected. The levels of TBARS were increased and the vitamin E concentrations were decreased significantly both in the cerebrum and cerebellum in 5%-EtOH group as well as in 2.5g-EtOH group. These results show that lipid peroxidation and vitamin E concentration in liver were varied according to the conditions of ethanol treatment, however, the vitamin E contents in cerebrum and cerebellum were affected by both ethanol intoxications used in this study.

• Journal of Food Hygiene and Safety
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• v.5 no.4
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• pp.187-196
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• 1990

This study was carried out to develop new model for gastric ulcer and to investigate some factor which effect it. Rats were immersed for 8 hours. Ulcer index was measured from total length of occured ulcer. Ulcer index (UI) of restraint and immersion group was higher significantly than that of only restraint group (p<0.001) and ulcer was occurred within only glandular stomach. UI of low water temperature group was higher significantly than that of high water temperature group (p

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.5
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• pp.1741-1751
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• 2013

The main purpose of this study is to investigate the static behavior of a prestressed concrete (PSC) girder using pre-tension method. A 30m long full-scale pretension PSC girder is fabricated by the portable fabrication system and tested. All results have been compared to those obtained from F.E.A results. Deflections at the middle of girders have been measured for evaluation. Also, strains of concrete at the middle of span have been measured. From the results of experimental, the load when initial crack was developed was obtained to be 1.75 time the unfactered design load in the full-scale girder specimen. Also, the data of specimen are satisfied the desgin requirements of ductility on the Korea Bridge Design Specification(2010). In service state, the vertical deflection at center of test specimen when a initial crack was developed is satisfied the vertical deflection requirement under live load of the Korea Bridge Design Specification(2010). To verify the experimental results, we numerical analyze the test and confirmed that the data were similar with results from the test above. The pretension girder fabricated in site were found to have enough strength for safety under and after construction.

• KSBB Journal
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• v.24 no.2
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• pp.131-139
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• 2009

The objective of this study was to evaluate the protective effect of aqueous extracts from Tremella fuciformis Berk(Tf AE) against stress during long-term and short-term in ICR mice. All the animals were randomly divided into two groups which had been bred for 5 months that were treated by immobilization stress for 8 weeks (total 7 months breeding, equivalent to human beings aged 20) with or without Tf AE, and one out of two groups was continuously bred until they become 18 months old (equivalent to human beings aged 60) without Tf AE. Afterwards, the changes of serum and hepatic metabolites were investigated on the basis of the index of stress-related in vivo oxidative damage. As a result, it was found that stress increases serum triglyceride (TG) and aspartate aminotransferase (AST) and decreases serum HDL-cholesterol in the long-term (total 18 months breeding) and short-term (total 7 months breeding). In addition, stress concerned the decrease of total antioxidant status (TAS) and superoxide dismutase (SOD) as well as the increase of malondialdehyde (MDA) in liver. On the other hand, Tf AE-fed groups reversed all these biochemical indices. These results suggest that stress in one's youth causes negative results in TG, HDL-cholesterol, LDL-cholesterol, AST, TAS, SOD and MDA measured in one's senescent. The administration of Tf AE in the stressed mice decreases serum TG and AST that are increased by stress, and exerts influence on the increase of serum HDL-cholesterol. Also Tf AE recovered the values of liver TAS, SOD and MDA in the stressed mice. In conclusion, Tf AE represented protective effect in the stressed mice to some degree.

• Journal of the Korean Institute of Navigation
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• v.25 no.3
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• pp.257-268
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• 2001

Marine traffic engineering is the technical field that observe flows of vessel traffic in accurate and describe the features of ships' movement statistically or analytically, then contribute to the improvement of the traffic flow and safety of traffic. Recently, marine traffic engineering has been developed until that possible to estimate a changes in traffic flow caused from some transformations of the traffic condition, and to assess the feasibility and validity of the changes by computer simulation. This paper aims to assess the present traffic safety at the sea area adjacent to Pusan harbour, and the validity of the suggested roundabouts traffic separation scheme at the Pusan approaching water(by Park in 1998) using environmental stress aggregation model There are couple of steps to describe the marine traffic situation and to assess it's safety by computer simulation. The first step is observe the movement of vessel traffic concerned waters and to obtain the relevant data for computer simulation. Second step is to carry out computer simulation to assess the simulated traffic flows by using suitable indexes of assessment model - environmental stress aggregation model. Eventually, this paper conclude that the environmental stress aggregation model is a useful technique to assess the traffic safety and the suggested roundabouts traffic separation scheme could make the concerned area safer than present traffic situation.

• Journal of the Korea Institute of Building Construction
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• v.13 no.2
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• pp.169-180
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• 2013

This paper presents the path model that defines a causal relationship between the construction workers' personal characteristics and their safety behavior at job-site. The personal characteristics and the safety behaviors which should be incorporated into the theoretical model were identified and established by conducting literature survey.. The model was verified by administrating survey questionnaires to the 399 construction workers who are actively engaged in construction job-sites located in Daegu metropolitan city and Kyungpook province. The data obtained from the respondents were statistically analyzed using SPSS18 and AMOS18. It is confirmed that safety behavior is directly affected by sincerity, openness, and extroversions. In addition, it is indirectly affected by stress reaction, safety motivation, and safety knowledge as well.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1390-1401
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• 2020

This study is a descriptive research to identify the relationship among violence experience, resilience and job stress of nurses working in emergency department. The subjects of this study were 143 nurses with over one year working in emergency departments of 6 hospitals located in D city and C city and collected data through structured questionnaire. It was from November 6th to November 15th. The degree of violent experience of the subjects was 1.26 ± 1.31 out of 4. The average score of resillience was 2.50 ± 0.55 out of 4. The average score of job stress was 3.62 ± 0.49 out of 5. The result of correlation between violence experience, resilience and job stress, among the sub factors, in the correlation among violence experience and job stress sub factors, verbal violence experience was significantly positively correlated with nursing work(r=.194, p=.010), role conflict stress(r=.158, p=.030), and physical threat experience was positively correlated with nursing work(r=.200, p=.008), role conflict(r=.162, p=.027), and conflict with doctor(r=.145, p=.042). In the correlation between resilience and job stress sub factors, nursing work stress is hardness(r=-.189, p=.012), persistence(r=-.165, p=.025), and optimism (r=-.186, p=.013) and there was a negative correlation with the region. Expertise stress is hardness(r=-.230, p=.003), persistence(r=-.195, p=.010), optimistic(r=-.194, p=.010) and there was a negative correlation. Nurse-treated stress was positively correlated with spirituality(r=.154, p=.033). In the subcategory correlations of resilience and violent experience, the hardness had a negative correlation with the physical threat(r=-.150, p=.037) experience. The persistence was negatively correlated with the experience of physical threats(r=-.138, p=.050). The optimism was negatively correlated with the experience of physical violence(r=-.151, p=.036). As a result, it is necessary to create a safe working environment free from violence and to reinforce training on how to deal with violence in order to reduce the job stress of emergency department nurses. In addition, measures to cope with stress according to age and work experience and programs to increase resilience should be developed and mediated to reduce the job stress of emergency department nurses.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.202-209
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• 2015

We investigated the effect of Capsosiphon fulvescens (CFE) and pheophorbide a (PhA) contained in CFE on oxidative stress regarded as a factor for diabetic complication. Streptozotocin (STZ), known as an oxidative stress inducer, was intraperitoneal injected for causing diabetes. After 7 days, CFE (4 and 20 mg/kg body weight) and PhA (0.2 mg/kg body weight) were treated once a day for 9 weeks. After the sacrifice, testis tissues were collected for the experiments. We confirmed that the treatment with CFE and PhA in diabetic animals not only decreased level of lipid peroxidation and serum nitric oxide compared with the diabetes group, but also the activities of glutathione peroxidase and glutathione-S-transferase were restored remarkably. Furthermore the activity of antioxidant enzymes, catalase and superoxide dismutase, were significantly recovered. With these results, our study suggest that CFE containing PhA may prevent seminal glands damages induced by oxidative stress in diabetic condition.