• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.435-436
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• 2006

This study focused on the introduction of the self healing technique for polymeric composites and evaluated the healing efficiency by the use of the interlaminar toughness fracture test. The DCPD (dicyclopentadiene) and ENB (5-ethylidene-2-norbornene) were used for the healing agent and the Grubbs' catalyst was used for the catalyst. According to the results, healing efficiency was found to be 37.9%, 22.3%, 26.3%, 22.8%, 30.8%, 30.8%, 33.0%, 33.4% for mode II fraction of 0%, 20%, 35%, 50%, 65%, 80%, 90%, 100%, respectively.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.531-538
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• 2022

In this study, the self-healing hybrid capsules were prepared, were mixed with 3 %, 5 %, and 7 % based on cement mass. The healing performance were evaluated according to mixing ratio self-healing hybrid capsule. As a result of the experiment, it was found that the crack healing performance improved as the mixing rate of the self-healing hybrid capsule increased, but the quality performance tended to decrease. Therefore, it is judged that using the mixing ratio of the hybrid capsule within 5 % reduces the quality performance to within about 10 % and secures about 90 % or more of the healing performance.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.383-388
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• 2021

In this study, constant head water permeability test was adopted to evaluate self-healing performance of mortars containing inorganic healing materials which consist of blast furnace slag, sodium sulfate and anhydrite. Clinker powder and sand replaced for a part of cement and fine aggregates. On constant head water permeability test for self-healing mortars, unit water flow rate of mortar specimens were measured according to crack width and healing period. As a result of evaluating the healing performance of self-healing mortar, it was confirmed that with the initial crack width of 0.3mm, the healing rate at healing period of 28 days increased by more than 30%p compared to plain mortar, greatly improving the healing performance. Furthermore, the coefficient(α) which was estimated from the relationship between crack width and unit water flow rate was used for calculating equivalent crack width. By analyzing the correlation of healing rate and equivalent crack width, the time and initial crack width attaining healing target crack width were predicted.

• Journal of The Korea Institute of Healthcare Architecture
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• v.15 no.4
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• pp.3-11
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• 2009

As de-schooling students (students who leave schools) have been produced and increased in middle and high schools every year since 1990s, urban alternative schools have founded with Seoul as the center. The objects of such urban alternative schools are de-schooling teenagers, and their educational goal is to make the students to discover their own values and grow as members of the community by accomplishing their healing and growth. Most of students in alternative schools have excessive self-centered feeling than ordinary people, and since they don't have exchanges with others, they have to receive holistic healing along with education. Here, 'healing' is a method of approaching to health through environmental, psychological, social and cultural supports unlike 'treatment' used for medical means. Therefore, holistic healing for alternative schools' students has to accomplish self-knowledge, self-control, and self-healing without repulsion through spaces of healing environments instead of heavy-handed exchanges. This study has integrated a theory of Max $L{\ddot{u}}scher$ who suggested a psychological healing theory in terms of internal character and a theory of Rudolf Steiner who suggested it in terms of practical and holistic sense and analyzed Sungmisan School, one of urban alternative schools in Seoul through the integrated theory. The analysis of the integrated theory are intended to emphasize the importance of healing environments and suggest methods in creating healing environments for urban alternative schools in the future.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.397-404
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• 2021

In this study, it was reviewed that the effect of solid capsules on the quality of surface repair materials and the healing properties of long-term aging, as part of a study to utilize self-healing surface repair materials using solid capsules as repair materials. As a result of evaluation of the rheological properties of self-healing surface repair materials according to the mixing of solid capsules, plastic viscosity, yield stress, and table flow tended to decrease. In the case of compressive strength, 1MPa per 1% of the solid capsule decreased proportionally. As a result of evaluating the long-term healing properties, when 10% of solid capsules were mixed, a healing rate of 90% was shown at 28 days of healing, because the solid capsule was preserved even after 91 days of age had elapsed. after 91 days of healing, even in the case of 5% of solid capsules, a healing rate of 90% was shown.

• Journal of Korean Academy of Rural Health Nursing
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• v.15 no.1
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• pp.16-29
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• 2020

Purpose: The purpose of this study was to determine the effect on depression and self-esteem in elders taking part in the Magma healing program. Methods: This study was a single group pre-post quasi-experimental design. The participants were elders over 60 who had complained of depression more than once within the last 3 months, and who were living in the jurisdiction of a health clinic in the 3-area of Chungnam. Data from 14 elders who participated in the Magma healing program were analyzed using nonparametric paired t-test with SPSS 25.0. Results: The study results showed that the Magma healing program had statistically significant results in reducing depression (z=-2.91, p=.004) and improving self-esteem (z=-2.91, p=.004) in elders. Conclusion: The Magma healing program has been proven to be a very useful program to reduce depression in elders and promote self-esteem, thereby integrating their lives and leading to successful aging.

• Macromolecular Research
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• v.12 no.5
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• pp.478-483
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• 2004

Two different diene monomers [dicyclopentadiene (DCPD) and 5-ethylidene-2-norbornene (ENB)] as self-healing agents for polymeric composites were microencapsuled by in situ polymerization of urea and formaldehyde. We obtained plots of the storage modulus (G') and tan $\delta$ as a function of cure time by using dynamic mechanical analysis to investigate the cure behavior of the unreacted self-healing agent mixture in the presence of a catalyst. Glass transition temperatures (T$\_$g/) and exothermic reactions of samples cured for 5 and 120 min in the presence of different amounts of the catalyst were analyzed by differential scanning calorimetry. Of the two dienes, ENB may have advantages as a self-healing agent because, when cured under same conditions as DCPD, it reacts much faster in the presence of a much lower amount of catalyst, has no melting point, and produces a resin that has a higher value of T$\_$g/. Microcapsules containing the healing agent were successfully formed from both of the diene monomers and were characterized by thermogravimetric analysis. Optical microscopy and a particle size analyzer were employed to observe the morphology and size distribution, respectively, of the microcapsules. The microcapsules exhibited similar thermal properties as well as particle shapes and sizes.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.59-66
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• 2020

In this study, self - healing solid capsules of crystal growth type which can be mixed directly with repair mortar were prepared, and the quality and crack healing performance of repair mortar with self - healing solid capsules were evaluated. The table flow and the air flow rate of the repair mortar material mixed with self-healing solid capsules were found to have no significant influence on table flow and air volume regardless of mixing ratio. Compressive strength tended to decrease with increasing capsule mixing ratio. As a result of evaluation of crack healing properties according to constant water head permeability test, initial water permeability decreased, and reaction products were generated over time and cracks were healed.

• Journal of the Korea Concrete Institute
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• v.29 no.1
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• pp.11-21
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• 2017

The paper presents experimental results of self-healing effects of OPC-GGBFS paste with cracked and uncracked specimens. The self-healing of cracked specimens is processes of crack closing with re-hydration of unhydrated in crack surface. The OPC paste with GGBFS replacement ratios of 0%, 10%, 20% and 30% were prepared having a constant water-binder ratios of 0.5. The OPC-GGBFS paste specimens immersed in tap-water and sea-water. The temperature of tap and sea-water was $5^{\circ}C$, $15^{\circ}C$ and $25^{\circ}C$. The cracked specimens after deterioration were immersed for 60 days. The relationship between self-healing effect and age-effect was calculate based upon the experimental results. The self-healing effect was measured in ultrasonic pulse velocity (UPV) before and after loading. When the relative change rate of UPV is increases with the increase in GGBFS replacement ratios. Moreover, the self-healing effect is increased with the temperature of tap-water is increase. But the cracked specimens immersed in sea-water was unclear effects of different temperature. Furemore, most of the healing for OPC-GGBFS specimens immersed in tap-water and sea-water occurred during the first 30 days. The self-healing effect until 30 days is higher than that the age-effect. After 30 days, self-effect and age-effect was largely decreases. SEM/EDS analysis of crack on the surface of the specimens in tap-water were covered with aragonite, and sea-water were covered with brucite.

• Journal of Digital Convergence
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• v.10 no.1
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• pp.349-355
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• 2012

Today, the computing environments is very complex, so researches that endow a system with the self-healing's ability that recognizes problem arising in a target system are being an important issues. However, the existing methodology, the goal for the new requirements for self-healing system developers to model and analyze the constraints that must be greater efforts. Therefore, in this paper are aware of problems detected by the system to solve the problem is the analysis of goal-based scenarios. In addition, there is a pre and post applying a strategy to be dynamically reconfigured to show you how to self-healing. These proposed new requirements for methodology, self-healing reduces the load on the developer's analysis.