• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.359-366
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• 2021

In this study, It was developed an monitoring cracks system based on image processing techniques in order to measure cracks, which are major damages in concrete, and to convert them into a database. The crack monitoring system consists of crack image captured equipment and a crack detection and analysis software. This system provides objective and quantitative data by replacing the conventional visual inspection. The crack detection algorithm w as verified through an indoor test using virtual cracks, and the amount of crack detection and crack width change was monitored by applying it to the self-healing repair mortar construction site. In the case of the crack width detected through image analysis, the maximum difference from the actual crack width was 0.0334mm. It was possible to detect microcracks of 0.1mm or less, and the effect of crack healing over time of the self-healing repair mortar was confirmed trough the field test.

• The Journal of the Korea Contents Association
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• v.22 no.7
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• pp.370-383
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• 2022

The purpose of this study is to propose an art healing program that can be used in the field to improve the quality of life and positive interaction between the elderly with mild dementia and their spouses. Therefore, after considering the preceding studies, the art healing program was constructed in five stages: survey-analysis-design-plan-implementation and evaluation based on theoretical discourse. In addition, by pilot application to the elderly with mild dementia and their spouses using the Y Dementia Relief Center, the art healing program provides internal positive resources, strengthens mutually beneficial resources between husband and wife, and improves life satisfaction and happiness by experiencing relationships with neighbors in the local community. was confirmed to be effective. This study is significant in that it proposes an art healing support plan that supports dementia patients and their families together before entering a super-aging society.

• Sleep Medicine and Psychophysiology
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• v.25 no.2
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• pp.58-67
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• 2018

Objectives: The purpose of this pilot study was to examine the effects of a mindfulness-based Body-Mind Intervention Program using marine resources on the improvement of quality of sleep, mood symptoms, and cognitive function in Korean female emotional labor workers. Methods: Twelve female workers who experienced excess emotional labor participated at the training camp program for five days in Danghangpo-ocean park, Goseung-gun, Gyeongnam Province in South Korea. Participant sleep quality, mood symptoms, and cognitive functioning before, after, and 1.5 months later were evaluated and analyzed. Results: After participating in the marine resource program, participants reported significantly decreased sleep latency. Global sleep quality, cognitive functions (attention, flexibility, and inhibition control), and mood states, including depression, tension, anger, fatigue, were also improved. These effects were generally maintained after 1. 5 months (PSQI t = 2.63, p = 0.02 ; HAM-D t = 5.92, p < 0.001). Conclusion: A Body-Mind Intervention Program using marine resources was effective in relaxing emotion-related tension and improving cognitive function. To advance this pilot study, it is necessary to carry out further research to investigate the use of marine resources in mental health interventions.

• Proceedings of the Korean Society of Computer Information Conference
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• 2016.07a
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• pp.3-4
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• 2016

멀티스레드 프로그램의 수행 중에 발생할 수 있는 자료경합은 프로그래머가 의도하지 않은 비결정적 수행으로 인해 신뢰할 수 없는 프로그램의 결과를 발생시킨다. 이러한 자료경합의 디버깅을 위해서 시간 및 자원적 비용이 과도하게 발생하기 때문에 프로그램의 수행 중에 이를 용인하고 치유하는 것이 중요하다. 본 논문은 멀티스레드 프로그램을 대상으로 소프트웨어 트랜잭셔널 메모리(STM)를 사용하여 공유변수에 대한 트랜잭션 영역을 설정하고 공유변수에 대한 이벤트 충돌 유형에 따른 자료경합 치유기법을 설계한다. 최종적으로는 프로그램 수행 중에 자료경합을 치유하는 기법의 실현가능성을 확인한다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.29-36
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• 2019

This study investigated the self-healing properties of blast furnace slag cement paste sample with $Na_2SO_4$ as a blast furnace slag activator after conducting the permeability test. Self-healing properties were examined by crack filling ratio and quantification of self-healing products. The degree of self-healing was evaluated by the crack filling ratio, and the crack filling ratio was analyzed by panoramic analysis using BSE-DIP for objectivity. The average crack filling ratio showed a tendency of decreasing from the upper part of the specimen to the lower part as the average of the top part was 18%, the middle part was 7% and the bottom part was 5% on average. The maximum crack filling ratio was 44% and the minimum crack filling ratio was 3%. The residual self-healing product after the permeability test contained a large amount of Ca element and Al element derived from the blast furnace slag, and the Si element was mainly present near the crack surface. The most abundant minerals in self-healing products were about 68% C-A-H. $CaCO_3$ was about 13% and C-A-S-H was about 8%. Three minerals accounted for 90% of self-healing products. C-A-H was mainly present at a part slightly distant from the crack surface and showed an angular or acicular shape. The C-A-S-H was generated on the surface naturally connected to the existing specimen, and the $CaCO_3$ was generally observed on the surface of the specimen or the inside of the crack.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.1
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• pp.92-100
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• 2022

In this paper, to evaluate the effect of SC on the crack self-healing performance and mechanical recovery performance of cement composites, encapsulated intumescent inorganic material-based solid healing materials were prepared. SC was mixed with cement composite materials to evaluate the basic properties, permeability test, and load reload test. SC slightly improved the flow of cement composites, and the compressive strength decreased by about 10 %. Also, the flexural strength decreased by about 30 %. It was found that when SC was mixed with the cement composite material by 5 %, the crack self-healing rate of Plain was improved by about 𝜟10 %. As a result of the load reload test, it was found that the mechanical recovery rate of Plain was improved by about 𝜟20 %. In addition, as a result of analyzing the correlation between the crack self-healing rate and the mechanical recovery rate by the load reload test, it is judged that the healing area of the Plain can be increased due to SC.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.561-568
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• 2022

In this study, the mechanical properties and self-healing performance of cement mortar containing clinker binder, calcium sulfoaluminate(CSA), and sodium sulfate(Na₂SO₄) were evaluated. The mechanical properties of cement mortar were investigated by measuring compressive strength and flexural strength, and the healing performance was evaluated through hydrostatic water permeability test and gas diffusion test. In addition, the healing products precipitated in the cracks were visually observed through an optical microscope and a scanning electron microscope(SEM). As a result, the incorporation of the clinker binder-based inorganic additives improved the initial and 28-day strength by about 20 %. Depending on the healing performance evaluation method, there was a difference in the healing rate, and the healing rate showed a tendency to be underestimated. Nevertheless, CaCO₃ was precipitated as the main healing product inside the 0.3 mm crack when the inorganic additives were mixed with cement mortar, improving the self-healing performance.

• Journal of Korea Entertainment Industry Association
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• v.13 no.2
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• pp.57-65
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• 2019

This study is a scientific approach to psychological factors such as emotional stability among various effects of forest resources. In order to carry out this study, the experiment was conducted on the subjects by setting the forest healing space as various spaces. The subjects who participated in this experiment were the students in their twenties and the average age was 22±1.25 years. The subjects were assessed for emotional words through subjective sequence evaluation in different designated forest healing spot. In addition, the emotional states that they actually perceived were measured by measuring the bio-signals to their perceived emotions. BMP, SDNN, VLF, LF, HF, Amplitude, and PPI were used for the bio-signal reaction experiment applied to this study. The results of this experiment were measured by Friedman test and Wilcoxon test for statistical analysis. n this study, 'good', 'clear', and 'uncomfortable' words were found statistically significant at the spot of forest healing space for subjective emotional vocabulary. In addition, SDNN, HF and Amplitude were statistically significant in the results of quantitative bio-signal measurement at each spot in the forest healing space. Based on the results of this study, we can suggest the application direction and strategic utilization plan of forest healing spot and forest resource utilization field. This is not only a guide for the users who use the facility through the spatial facilities and physical requirements for the emotion based forest-healing, but also can be used as a personalized emotional space design aspect.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.81-87
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• 2020

Crack control is essential to increase the durability of concrete significantly. Healing of crack can be controlled by rehydration of unreacted clinkers at the crack surface. In this paper, by comparing the results of isothermal calorimetry test and regression analysis, the Parrot & Killoh's cement hydration model was verified and clink er hydration model was proposed. The composition and quantification of hydration products were simulated by combining kinematic hydration model and thermodynamic model. Hydration simulation was conducted using the verified and proposed hydration model, and the simulation was performed by the substitution rate of clink er. The type and quantity of the final hydration product and healing product were predicted and, in addition, the optimal cementitious material of self-healing concrete was selected using the proposed hydration model.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.593-599
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• 2022

In this study, a crack monitoring system capable of detecting cracks based on image processing techniques was developed to effectively check cracks, which are the main damage of concrete structures, and a program capable of imaging and analyzing cracks was developed using machine vision. This system provides objective and quantitative data by replacing the appearance inspection that checks cracks with the naked eye. The verification of the development system was applied to the construction site of a self-healing concrete water tank to monitor the crack and the amount of change in the crack width according to age. In the case of crack width detected by image analysis, the difference from the measured value using a digital microscope was up to 0.036 mm, and the crack healing effect of self-healing concrete could be confirmed through the reduction of crack width.