• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.581-589
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• 2020

In this paper, a solid capsule was prepared using a crystal growth type inorganic material capable of hydration reaction, the quality and mechanical healing properties of self-healing mortar with solid capsules were evaluated. Solid capsules were mixed 5% by mass of cement. Reloading test results of compressive load, it was found to improve about 20% on average for the natural healing effect of Plain, in the case of the elastic range, the healing rate was about 79% at the 7 days of healing age and 98% at the 28 days of healing age. Reload test results of flexural load, in the case of the elastic range, the healing rate was about 79% at the 7 days of healing age and 98% at the 28 days of healing age. Through these results, it is judged that the healing performance of solid capsules has also an effect on mechanical healing properties such as strength in addition to the durability properties obtained by the permeability test. Since the strength tends to decrease as the solid capsules are mixed, it is considered necessary to compensate.

• 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.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.315-318
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• 2011

본 논문에서는 구조물 연결부의 실시간 손상 검색을 통해 이상이 감지되었을 경우 자가치유까지 가능한 지능형 볼트접합부 시스템에 관한 실험적 연구결과가 제시되었다. 지능형 센서인 PZT센서의 전기-역학적 커플링 특성을 이용한 전기역학적 임피던스 기반의 구조물 건전성 평가 방법이 사용되었다. 전기역학적 임피던스의 측정을 통한 계측값을 베이스라인 값과 비교하는 손상 평가를 통해 구조물 볼트접합부의 볼트풀림 손상을 진단하고, 손상은 손상지수 RMSD를 통하여 정량화되었다. 볼트접합부의 손상이 감지되었을 경우 형상기억합금(SMA) 와셔에 부착되어있는 히팅 필름에 전원을 가함으로써 형상기억합금에 열을 가하고, 가열된 형상기억합금 와셔는 축방향으로 팽창을 함으로써 잃었던 볼트의 토크력을 회복시켜주었다. 실험 결과, 제안된 전기역학적 임피던스 기반의 구조물 건전성 평가기법과 형상기억합금 와셔 기반의 볼트접합부 자가치유 시스템의 성능 평가와 검증이 이루어졌다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.134-142
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• 2020

In this study, in order to evaluate the self-healing performance of cement composites the self-healing test method and the analysis method were suggested by applying constant water head permeability test, chloride migration test and repeated bending test. The method of making a cracked specimen and controlling crack width are also proposed. Constant head water permeability test can evaluate the healing performance by using the decreasing rate of water flow passing through the crack zone of a specimen. Furthermore, the equivalent crack width can be used to intuitively investigate the healing effect with healing period. The chloride migration test can evaluate the healing rate by the decreasing rate of the diffusion coefficient obtained by ASTM C 1202. Mechanical healing performance can be evaluated using ISR and IDR estimated from load vs. CMOD relationship graph obtained through the repeated bending test. Finally, the applicability of proposed self-healing evaluation methods was examined by testing mortar specimens with or without self-healing agents.

• Journal of Korean Society of Steel Construction
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• v.23 no.5
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• pp.629-636
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• 2011

This paper describes the smart structural system that uses smart materials for real-time monitoring and active control of bolted joints in steel structures. The impedance-based structural health monitoring (SHM) techniques, which utilize the electro-mechanical coupling property of piezoelectric materials, was used to detect loose bolts in bolted joints. By monitoring the measured electrical impedance and comparing it with the measured baseline, a bolt loosening damage was detected. The damage was evaluated quantitatively using the damage metrics in conductance signature with respect to the healthy states. When loosening damage was detected in the bolted joint, the external heater actuated the shape memory alloy (SMA) washer. Then the heated SMA washer expanded axially and adjusted the bolt tension to restore the lost torque. An experiment was conducted by integrating the piezoelectric-material-based SHM function and the SMA-based active control function on a bolted joint, after which the performance of thesmart self-healing joint system was investigated.

• Journal of Korean Orthopaedic Sports Medicine
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• v.7 no.1
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• pp.1-7
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• 2008

일반적으로 진행된 골관절염 등 골연골 병변에 대해서는 골연골을 치유시키는 술식에서부터 인공 관절 치환술까지 치료방법이 다양하게 보고되고 있다. 특히 견관절 인공 관절 치환술을 비롯한 여러 수술 방법에 대한 적응증 및 금기증을 잘 숙지하고, 각각의 고유 질병에 따른 병리 소견과 견관절의 정상적 해부학 및 생역학을 이해하며, 적절한 기구 선택과 정확한 술기로 수술을 시행할 때 제한된 치료 목표이지만 보다 긍정적인 치료 결과를 예측할 수 있다.

• Korean Journal of Head & Neck Oncology
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• v.2 no.1
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• pp.13-22
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• 1986

Nasal fossae 의 암이란 비강과 부비동들에서 발생하는 것으로서 환자를 가장 괴롭히며 또한 가장 믿을수 없는 악성종양들중의 하나이다. 비록 본 예수병원 암환자 등록부에 의하면 전 암환자의 2.2% 발생빈도로서 주요한 발생빈도를 보이지는 않지만, 이 부위의 암을 치유하는데는 세심하고 철저한 모든 진단적 검사와 과감한 외과 및 치료방사선의 병합치료가 요구된다. 저자들은 지난 22 년간 비강 및 부비동 (Nasal fossae) 에서 발생한 원발성 악성종양중 치유목적의 근치수술을 시행한 68 예를 임상고찰 하였다. 근치수술을 시행했던 68 예중 91% 에서 제 3 병기 또는 4 병기의 진행된 경우 이었다. 외과적 수술은 한예의 사골동 (篩骨洞) 종양적출술 및 부분상악동(上顎洞)절제술 한 예를 제외한 66 예 모두에서 전상악동(全上顎洞)절제술 (total maxillectomy) 또는 확장 전상악동(全上顎洞)절제술 (extended total maxillectomy) 을 시 하였다. 저자들은 역학적(疫學的), 병리학적(病理學的), 병기(病期) 및 치료, 재발율과 생존율들을 분석 고찰하였으며 3가지 치료형태를 서로 비교하였다. 즉 수술만 시행한 군, 수술전 방사선 치료 및 수술병합군, 수술과 수술후 방사선치료 병합 군으로 나눴다. 저자들의 예비적 (preliminary) 관찰 결과는 2 년간 무병생존율 (disease-free 2-year survival) 만을 볼때, 수술만 시행한 군에서 40%로써 통계학적으로는 가장 좋았으나 실제는 수술만 시행한 군에서는 단지 40%만이 제 4 병기(病期)의 진행된 경우였으나 수술전 방사선치료 또는 수술후 방사선치료등의 병합치료에서는 제 4 병기(病期)의 진행된 상태가 무려 60 %나 되었다. 전체적인 재발율 (Overall recurrence rate) 은 68.2%로써 무서울 정도로 높았으며 전체적인 2 년 무병율은 23.7%였다. 저자들은 이 분야에서 실패의 원인분석과 치료방법의 선택등에 대한 지침을 제시하고저 한다.

• Clinics in Shoulder and Elbow
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• v.10 no.2
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• pp.155-159
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• 2007

Arthroscopic single-row rotator cuff repair is a well established surgical technique for the treatment of rotator cuff tears. However, the problem of postoperative retear remains a concern. Various avenues are being explored to address this problem. Some studies have suggested that restoring the anatomical footprint may improve the healing and initial strength of the repaired rotator cuff tendon. The double-row technique was introduced as a method of reconstructing the anatomical footprint. According to biomechanical studies on cadavers, this technique improved mechanical strength and reduced gap formation. However, the biological properties of reattached tendon such as tension, and vascularity have not been proved yet. Furthermore, the apparent mechanical superiority of the double-row over the single-row construction has not resulted in better functional outcomes. Therefore, the less complicated and less costly single-row technique is still the recommended treatment for rotator cuff repairs.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.4
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• pp.338-344
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• 2016

Implant supported removable partial denture (ISRPD) using the implants enables favorable rehabilitation by complementing biomechanical limitations of the conventional removable partial denture (RPD). However, continuous recall check is necessary for evaluation of the mechanical and biological complications to ensure good long-term prognosis of ISRPD. This clinical report describes the complication and management in patient of Kennedy class I edentulism with ISRPD using healing abutment. The wear and fracture of healing abutment occurred at 36 months after delivery. So, healing abutment was replaced by connecting $Locator^{(R)}$ abutment for altering into the implant retained partial overdenture.

• Korean Journal of Culture and Social Issue
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• v.11 no.spc
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• pp.85-95
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• 2005

The present article explored the studies on the relational mechanisms between trust and health in terms of psychosomatic medicine or integrative medicine. For this, the research findings of the Quantum physics, psychosomatic medicine, and traditional eastern healing methods on the mind-body problem and then a practical guide to greater physical and mental well-being is presented. In the first section of the Quantum mechanical human body, the body has a mind of its own, the mechanism and cause of disease, the body as objective experienced conscious, and the effects of consciousness and information on the body are includes. The second section is psychosomatic medicine. In this, the thought changing brain, placebo, the power of expectancy, achieving health by active endeavor, psychoneuroimmunology, and the several therapies are included. Finally, Dr. Benson and Proctor's practical guide to well-being in presented. It is emphasized that the four trusts (trust in oneself, one's doctor, one's treatment, and one's spiritual trust) are crucial to recovery from serious illness and to achieve better health.