• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.147-153
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• 2001

The major objectives of this study are to investigate experimental and analytical behavior of composite steel plate strengthened by external post prestressing method and to study the increasing magnitude of load carrying capacity by the external post prestressing method. With installed strain gauges and LVDT, the change of structural behaviors according to the amount of prestressing force is measured and the effects of shear strengthening according to the degree of angle in tendon are studied. The analytical structural behavior according to the amount of prestressing force is also investigated using finite element method. The effectiveness of strengthening of external post prestressing method is proved and an efficient FEM model is suggested by comparing the test results and analyzing results.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.139-146
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• 2001

Res system, with Reinforced Concrete columns and Steel beams, is defined as system in which both steel and concrete materials are efficiently combined to maximize the structural and economic advantages of each material. Tested in this study were 4 exterior beam-to-column joint specimens with variables that influence joint rigidity of RCS structure. The purpose of this study is to compare and analyze the structural behavior of exterior joints through the existing studies and tests, and offer basic data for practical use of RCS structure by studying flexible behavior(semi-rigid effect) of joints according to joint details.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.3
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• pp.125-131
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• 2003

This paper presents the characteristics of flexural behavior of RC beam strengthened with CFRP(Carbon Fiber Reinforced Polymer Plate). Experimental variables included the strengthening length, width, reinforcement ratio, end anchorage and preloading corresponding to 75 percent of ultimate capacity and the effects according to each experimental variables were analyzed. To study, a total 21 RC beams were constructed, tested and the response of the beams in terms of ultimate load, deflection, strain of CFRP, failure mode were examined.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.13 no.3
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• pp.409-418
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• 2006

Purpose: This study was done to identify the process of change, decisional balance and self-efficacy corresponding to stage of exercise behavior based on the Transtheoretical model in patients with chronic arthritis. Method: The participants were 151 patients with chronic arthritis using an out-patient pain clinic and hospital in C city. The collected data were analyzed using ANOVA, Sheffe test and discriminant analysis with SPSS/WIN. Results: The patients were distributed as follows for each stage of exercise behavior 21.8% in the precontemplation stage, 26.5% in the contemplation stage, 25.2% in the preparation stage, 7.3% in the action stage, and 19.2% in the maintenance stage. Significant effects for stage of change were found for nine of the 10 processes of change and Pros, Cons, self-efficacy. Scores on these variables were found to increase across the stage of exercise behaviors from precontemplation to maintenance. Discriminant analysis revealed that self-efficacy and stimulus control, and reinforcement management were the major correlates of the stage of exercise behaviors. Conclusion: The findings of this study give useful information for exercise intervention, by using strategies of exercise for chronic arthritis patients in different stages of exercise behavior.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.6
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• pp.215-219
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• 2010

The evaluation of the mechanical properties and behavior is very important for the design of embankment using granular materials. In this research, the lab. tests with Nak-dong river sand were conducted to find out mechanical properties related to stress-strain behavior. Also, numerical simulations which can express the behavior of granular material were conducted by distinct element method. Distinct element method can play a import role to predict stress-strain behavior for different confining stress and loading condition if micro-parameters can be estimated in specific condition.

• Smart Structures and Systems
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• v.15 no.3
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• pp.609-625
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• 2015

Management of infrastructure stock is essential in sustainability of society, and its analysis and optimization are studied in the light of control system modeling in this paper. At the first part of the paper, cost of stock management is analyzed based on macroscopic statistics on infrastructure stock and economical growth. Stock management burden relative to economy is observed to become larger at low economic growth periods in developed economies. Then, control system modeling of stock management is introduced and by augmenting maintenance actions as control input, dynamic behavior of stock is simulated and compared with existing time history statistics. Assuming steady state conditions, applicability of the model to cross sectional data is also demonstrated. The proposed model is enhanced so that both preventive and corrective maintenance can be included as system inputs, i.e., feedforward and feedback control inputs. Optimal management strategy to achieve specified deteriorated stock level with minimal cost, expressed in terms of preventive and corrective maintenance actions, is derived based on estimated parameter values for corrosion of steel bridges. Relative cost effectiveness of preventive maintenance is shown when target deteriorated stock level is lower.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1177-1190
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• 2010

The high-speed railway track occurs train operating result track irregularity, subsidence of the track, ballast abrasion. This is the unusual condition. High-speed railway track maintenance task is the behavior which repairs unusual section by using the human resource or machine resource. The resource used to maintenance task is restrictive. A resource can be efficiently used if the high-speed railway track maintenance scheduling is used. So the more task can be performed in the fit time. In conclusion, this manages the unusual condition of a track efficiently. So additional expenses is minimized cause by deteriorating unusual condition. And it offers comfortable ride to passenger. However, maintenance scheduling has to reflect well practical situation and environment. That's maintenance scheduling is used. We gather the opinions of the hands-on workers. So in this paper define field situation and condition. And suggest mathematical model about this. And we developed the track maintenance scheduling software engine using ILOG.

• Korean Journal of Adult Nursing
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• v.14 no.1
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• pp.83-92
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• 2002

Purpose: This study was performed to identify the process of change, decisional balance and self-efficacy corresponding to the stage of exercise behavior using Transtheoretical Model in patients with type 2 diabetes mellitus. Method: The study method was a survey in 100 type 2 DM patients at out-patients clinic of Y medical center from March 19, 2000 to October 30, 2000. Result: The results were as follows: The subjects were divided into five stages of exercise behavior ; 15.0% in pre-contemplation stage, 33.0% in contemplation stage, 17.0% in preparation stage, 16.0% in action stage and 19.0% in maintenance stage. The subjects in pre-contemplation stage used all processes of change in the least. "Dramatic relief(DR)", "Environmental reevaluation(ER)" and "Self reevaluation(SR)" were identified as main processes of change in contemplation stage. "Consciousness raising(CR)", "DR" were used higher than average in preparation stage. Helping relationships(HR)", "CR", "ER", "SR", "Social liberation(SL)", "Counter conditioning (CC)", "Reinforcement management(RM)", "Self iberation(SEL)" and "Stimulus control(SC)" were used higher than average in action stage. The subjects in maintenance stage used all process of change the highest except "DR"and "HR". "Cons" score of decisional balance was the highest in pre-contemplation stage, "Pros" score was the highest in action stage and "Self-efficacy" score was the highest in maintenance stage. Conclusion: This study can provide the basis of staged matching exercise program using TTM for more effective and useful intervention.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.4
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• pp.105-116
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• 2022

Domestic and foreign aviation industries showed steep growth along with rapid increase in aviation demand, but the industries got directly hit by COVID-19. Now, with the recovery of daily life, aviation demand is gradually increasing, too. However, the risk of aviation accidents also increases proportionally to the increasing demand for aviation. Although it is a point that safety management needs to be actively conducted to prevent safety accidents resulted from the growth of aviation industries, research on safety culture and organizations is not sufficiently done in terms of the depth and scope of it despite the importance of the discussion. Studies in various areas have reported that an organization's safety culture forms the group's safety atmosphere and then results in the workers' safety behavior. Accordingly, this study examined the effects of safety culture in an organization on the safety behavior of its members who are aircraft maintenance technicians. The results of this research can be summed up as follows: first, it has been found that the roles of the person in charge grounded on clear goals and guidelines for the organization's safety policy influence the technicians' attitudes. Second, the important factor in the technicians' safety observance is that the attitude to follow safety rules when performing aviation maintenance raises their awareness of safety, for instance, following standard operation procedures or wearing personal equipment for protection. Third, their attitudes have positive effects on safety participation, and consequently, their intention to comply with safety rules is shown as an active action to achieve the ultimate goal of safety behavior.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.10 no.2
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• pp.138-144
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• 2003

Purpose: The purpose of this study was to identify the change processes for exercise behaviors in each stage. Method: Participants for this study were randomly selected from adults between the ages of 20-44. Data were collected using questionnaires over a 2 week period at the end of May, 2003. The instrument, Stages of exercise behavior change developed by Marcus et al. (1992b), and the instrument, Changing phases of exercise behaviors developed by Nigg et al. (1999) and translated by Kwon (2002) were used to investigate the behaviors. Result: 1. Related to stage of exercise behavior change of participants, it was found that 55.2% of participants exercised regularly. 2. Among the change processes according to stage of change showed that dramatic relief was the most frequently used process for all stages. Environmental reevaluation and social liberation were used most in the contemplation stage, while environmental reevaluation and stimulus control were used most in the preparation stage. In addition, scores for stimulus control and environmental reevaluation were high in the action stage. In the maintenance stage, social liberation and counter-conditioning were used most frequently. 3. The process of exercise behavior change which differentiates the stages of exercise behavior change were shown to be counter-conditioning, which was an influential factor that differentiates the contemplation stage and maintenance stage. Conclusion: The results suggest that change process management should be the focus to enhance the stage of change for exercise in this group.