• Proceedings of the Computational Structural Engineering Institute Conference
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• 1994.10a
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• pp.152-159
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• 1994

One of the main objectives of the study is to propose a pratical and realistic reliability analysis by ETCM(Expected Total Cost Minimization). This study is intended to propose the safety assesment and capacity rating of existing reinforced concrete members by evaluating the safety evaluation index, that is RF(Rating Factor) from the results of the field test and inspection for 5 reinforced concrete bridges. ETCM method is used for the reliability analysis of the proposed models. The proposed reliability model and method are applied the safety assesment and system factors of reinforced concrete members.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.2
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• pp.25-38
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• 2017

Current limitation of Aviation airworthiness manage system and text based Aviation safety report data, lack of Data Manage system for aviation parts failure and lack of continuing airworthiness related to task linking system for Inspection/Report/Improvement(AD ; Airworthiness Directive) have been apprehended to suggest direction of realizing improved operating system by applying aviation airworthiness manage system by using standardization and safety performance index based managing and safety performance index based data analyzing.

• Advances in concrete construction
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• v.9 no.2
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• pp.149-159
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• 2020

The present work proposes new engineering models for determining corrosion initiation time in concrete reinforcing steels in marine environment. The models are based on Fick's second law that is commonly used for chloride diffusion. The latter is based on deterministic analyses involving the most influencing parameters such as distance of the concrete structure from the seaside, depth of steel concrete cover, ambient temperature, relative humidity and the water-cement ratio. However, a realistic corrosion initiation time cannot be estimated because of the uncertainties associated to the different parameters of the models. Therefore a reliability approach using FORM/SORM method has been applied to develop the proposed engineering models integrating a limit state function and a reliability index β. As a result, the corrosion initiation time is expressed by new exponential engineering models where the uncertainties are associated to the model parameters. The main emerging result is a realistic decision tool for corrosion planning inspection.

• Journal of the Korea Institute of Building Construction
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• v.13 no.1
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• pp.90-100
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• 2013

Deck-plates are widely used on construction sites, and have the advantage of enabling contractors to achieve a relatively uniform quality. But nevertheless, quality deviation in deck-plate construction can occur as the result of differences in site conditions and the experience of crew workers. In this study, the authors present a site quality evaluation prototype for building deck-plate construction. Through analyses of case studies and interviews with experts, standard quality check sheets and a quality management index were developed by estimating the importance of quality check items based on a Failure Mode and Effects Analysis (FMEA) method. The applicability and effectiveness of the prototype was evaluated through a case study and interviews with case participants. It was found that the prototype promoted an active quality management as a way of continuously improving quality management in deck-plate construction instead of passive quality inspection practice.

• Structural Monitoring and Maintenance
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• v.9 no.4
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• pp.373-388
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• 2022

A USW based diagnostic procedure is presented for estimating the depth of surface-breaking cracks. The diagnosis is demonstrated on seven lab-scale SFRC beam specimens, which are subjected to the CMOD controlled three-point bending test to create real bending cracks. Then, the recorded multiple ultrasonic signals are examined with the signal processing techniques, including wavelet transform and two-dimensional Fourier transform, to investigate the relationships between the crack depth and two diagnostic indices, namely the attenuation coefficient and dispersion index (DI). Finally, the reliabilities of these indices for depth estimation are verified with the visually measured crack depths as well as the crack features obtained with a digital image processing algorithm. It is found that the DI outperforms the attenuation coefficient in depth estimation, where this index displays good agreement with the visual inspection for 86% of the inspected specimens.

• Korea Science and Art Forum
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• v.20
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• pp.135-146
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• 2015

The purpose of this research is to highlight the importance of customer experience relating to servitization of manufacturing and to develop an index to analyze customer experience management. It occurred that customer experience management analysis should perform in diverse dimensions to get higher customer satisfaction. Following to this idea, new idex is designed : CEMC(Customer Experience Management Competency scale). CEMC includes three parties which are internal expert, external expert and customer, as evaluators of the appraisal. Each evaluator participates in the inspection about customer experience management through a questionnaire which composed four sections : Product and service, Business process, Culture and Asset. Researchers apply this index to one small manufacturing business and analyze the state of customer experience management. The result would be a reference for building strategy and align inside organization.

• Journal of Korean society of Dental Hygiene
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• v.7 no.2
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• pp.123-133
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• 2007

This document is about immigrant worker who use counseling office for human rights in the Daegu Gumin Church. We researched their oral health state so that we can understand their situation and support them properly. General characteristics of study subjects, habits related to oral health, the oral examination and treatment clinic, participated in oral heath education program were studied by designed administered questionaire. And decay, filling(treatment teeth), missing tooth(lost teeth by dental-caries)was counted by oral examination, and calculated DMFT-index. This study was done from the July, 9, 2006 to Aug. 8, 2006. In a total of 289 immigrant worker, 77.9% of them were men and 22.1% of them were women. 55.7% of their salary was from 1,000,000 won to 1,500,000 won and most of them were working for a fiber industry. Many of them are living in korea for more then three years. DMFT index for men was 2.77 and for women was 4.06 so average of DMFT index was 3.06. 46.7% of them said that they are healthy in oral health state. The question for having difficulty using dental clinic in korea, 65.1% of them said "it is difficult". First reason was a communication problem and second was time. Most of them didn't have a oral health education but 85.1% of them said that they are looking forward to attending oral health education. Immigrant worker had better DMFT index then that of korean blue color worker. But still it is quite difficult for them using dental clinic in korea also cost. It is necessary to support them properly that medical insurance system, medical facilities of quality, medical insurance subscriber beside, made by their language, manual for them. At once, medical service improvement a policy is necessary for immigrant worker in korea.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.3
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• pp.33-40
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• 2009

This paper proposes the assessment method for objective quality-evaluation-index of mosaic images. Quality assessment was evaluated using seam-line method and similarity and contrast of adjacent images. The evaluation measure was calculated based on selected evaluation criteria and compared with human visual inspection. It was found that quantitative quality evaluation measure showed that the evaluation results were similar to human visual check. Conclusively experimental results proved that proposed evaluation measure could be used for quantitative and objective quality assessment of mosaic images.

• Safety and Health at Work
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• v.6 no.4
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• pp.345-352
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• 2015

Background: Goal-oriented communication of risk of hazards is necessary in order to reduce risk of workers' exposure to chemicals. Adequate training of workers and enterprise priority setting are essential elements. Cleaning enterprises have many challenges and the existing paradigms influence the risk levels of these enterprises. Methods: Information on organization and enterprises' prioritization in training programs was gathered from cleaning enterprises. A measure of enterprises' conceptual level of importance of chemical health hazards and a model for working out the risk index (RI) indicating enterprises' conceptual risk level was established and used to categorize the enterprises. Results: In 72.3% of cases, training takes place concurrently with task performances and in 67.4% experienced workers conduct the trainings. There is disparity between employers' opinion on competence level of the workers and reality. Lower conceptual level of importance was observed for cleaning enterprises of different sizes compared with regional safety delegates and occupational hygienists. Risk index values show no difference in risk level between small and large enterprises. Conclusion: Training of cleaning workers lacks the prerequisite for suitability and effectiveness to counter risks of chemical health hazards. There is dereliction of duty by management in the sector resulting in a lack of competence among the cleaning workers. Instituting acceptable easily attainable safety competence level for cleaners will conduce to risk reduction, and enforcement of attainment of the competence level would be a positive step.

• Journal of Advanced Engineering and Technology
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• v.11 no.4
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• pp.245-251
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• 2018

Terahertz waves (T-ray) was extensively studied for the NDE (nondestructive evaluation) of characterization of trailing edges for a use of turbines composed with composite materials. The used NDE system were consisted of both CW(Continuous wave) and TDS (Time domain spectroscopy). The FRP composites were utilized for two kinds of both trailing edges of wind energy (non-conducting polymeric composites) and carbon fiber composites with conducting properties. The signals of T-ray in the TDS (Time domain spectroscopy) mode resembles almost that of ultrasound waves; however, a terahertz pulse could not penetrate a material with conductivity unlike ultrasound. Also, a method was suggested to obtain the "n" in the materials, which is called the refractive index (n). The data of refractive index (n) could be solved for the trailing edges. The trailing edges were scanned for characterization and inspection. C-scan and B-scan images were obtained and best optimal NDE techniques were suggested for complicated geometry samples by terahertz radiation. Especially, it is found that the defect image of T-ray corresponded with defect locations for the trailing edges of wind mill.