• Title/Summary/Keyword: Self-Repair

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A STUDY REPAIRED JOINT STRENGTH OF COMPLETE DENTURE (의치수리(義齒修理)에 있어 파절접합부(破折接合部)의 조작형태(造作形態)가 의치(義齒)의 결합력(結合力)에 미치는 영향(影響)에 관(關)한 연구(硏究))

  • Lee Woo-Hyun;Heo Seong-Joo;Cho In-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.29 no.3
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    • pp.101-110
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    • 1991
  • The purpose of this study was to compare the repaired joint strength among several edge profiles after denture repair. For this study, eight edge profiles were used for repair methods and five self-curing resin brands were used for repair materials. Break away loads were tested after 1 hr., 24 hrs. and 1 week. Instron was used for testing the transverse strength of repaired specimen. The results were as follows. 1. Repaired joint strength was about 35-65% of that of original specimen. 2. Joint strengths of round, inverse knife, inverse rabbit, lap ogee joint were higher tnan that of traditional simple butt joint 3. Joint strength of the simple butt joint was low significant. 4. Joint strengths after 1 hr. specimen were lower than those of 24 hrs. and 1 week specimens in joint strengths. 5. There were no significant differences between 24 hrs. and 1 week specimens in joint strengths. 6. It look more than 24 hours to gain satisfactory physical property after repairing the fractured denture base when self-curing resin was used for repair.

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Evaluating the bond strength between concrete substrate and repair mortars with full-factorial analysis

  • Felekoglu, Kamile Tosun;Felekoglu, Burcu;Tasan, A. Serdar;Felekoglu, Burak
    • Computers and Concrete
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    • v.12 no.5
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    • pp.651-668
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    • 2013
  • Concrete structures need repairing due to various reasons such as deteriorative effects, overloading, poor quality of workmanship and design failures. Cement based repair mortars are the most widely used solutions for concrete repair applications. Various factors may affect the bond strength between concrete substrate and repair mortars. In this paper, the effects of polymer additives, strength of the concrete substrate, surface roughness, surface wetness and aging on the bond between concrete substrate and repair mortar has been investigated. Full factorial experimental design is employed to investigate the main and interaction effects of these factors on the bond strength. Analysis of variance (ANOVA) under design of experiments (DOE) in Minitab 14 Statistical Software is used for the analysis. Results showed that the interaction bond strength is higher when the application surface is wet and strength of the concrete substrate is comparatively high. According to the results obtained from the analysis, the most effective repair mortar additive in terms of bonding efficiency was styrene butadiene rubber (SBR) within the investigated polymers and test conditions. This bonding ability improvement can be attributed to the self-flowing ability, high flexural strength and comparatively low air content of SBR modified repair mortars. On the other hand, styrene acrylate rubber (SAR) modified mortars was found incompatible with the concrete substrate.

Arthroscopically Assisted Repair of Large to Massive Rotator Cuff Tears -The Role of Acromioplasty- (중범위 이상 회전근 개 파열 환자의 관절경적 봉합술 -견봉성형술의 역할-)

  • Lee, Kwang-Won;Kim, Kap-Jung;Lee, Hang-Ho;Kim, Byung-Sung;Kim, Ha-Yong;Choi, Won-Sik
    • Clinics in Shoulder and Elbow
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    • v.6 no.2
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    • pp.143-148
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    • 2003
  • Objectives: To analyze the postoperative functional outcome of shoulder in patients with arthroscopically assisted repair of large to massive rotator cuff tears with or without acromioplasty and role of acromioplasty. Materials and Methods: From June 1996 to June 2002, twenty six patients with large to massive rotator cuff tears were undergone arthroscopically assisted repair. Mean follow up was over one year. Fourteen were male and twelve were female. Mean age was 51 years old(39-66). Mean duration was 9 months. Acromioplasty was done in 14 cases concomitantly. They were divided into two groups. Group I: arthroscopic cuff repair with acromioplasty(14 cases). Group II: arthroscopic cuff repair without acromioplasty(12 cases). Each shoulder was evaluated at preoperative and final follow-up with Visual Analogue Scale(VAS), University of Pennsylvania Patient self-assessment of pain, University of Pennsylvania Patient self-assessment of function, ASES standardized shoulder assessment form, Simple Shoulder Test, UCLA score and range of motion(ROM). We analyzed the differences between the two groups. Shoulder ROM and acromioplasty were determining factors. Statistics was tested by correlation analysis and repeated measure ANOVA test. Results: At the final follow up, functional outcome and pain were improved but they had no statistical significance between the two groups(p>0.05). Combined procedure, acromioplasty, didn't affect on VAS. UCLA score, University of Pennsylvania Patient self-assessment of pain, University of Pennsylvania Patient self-assessment of function, ASf:S standardized shoulder assessment form and Simple Shoulder Test(p>0.05). In group II, forward flexion and abduction were statistically improved at the final follow up than in group I(p<0.05). Conclusions: It appears that arthroscopic repair is satisfactory procedure in patients with large to massive cuff tears. Combined procedure, acromioplasty, doesn't affect on postoperative functional outcome of shoulder.

High Repair Efficiency BIRA Algorithm with a Line Fault Scheme

  • Han, Tae-Woo;Jeong, Woo-Sik;Park, Young-Kyu;Kang, Sung-Ho
    • ETRI Journal
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    • v.32 no.4
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    • pp.642-644
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    • 2010
  • With the rapid increase occurring in both the capacity and density of memory products, test and repair issues have become highly challenging. Memory repair is an effective and essential methodology for improving memory yield. An SoC utilizes built-in redundancy analysis (BIRA) with built-in self-test for improving memory yield and reliability. This letter proposes a new heuristic algorithm and new hardware architecture for the BIRA scheme. Experimental results indicate that the proposed algorithm shows near-optimal repair efficiency in combination with low area and time overheads.

Comparison of traditional and simplified methods for repairing CAD/CAM feldspathic ceramics

  • Carrabba, Michele;Vichi, Alessandro;Louca, Chris;Ferrari, Marco
    • The Journal of Advanced Prosthodontics
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    • v.9 no.4
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    • pp.257-264
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    • 2017
  • PURPOSE. To evaluate the adhesion to CAD/CAM feldspathic blocks by failure analysis and shear bond strength test (SBSt) of different restorative systems and different surface treatments, for purpose of moderate chipping repair. MATERIALS AND METHODS. A self-adhering flowable composite (Vertise Flow, Kerr) containing bi-functional phosphate monomers and a conventional flowable resin composite (Premise Flow, Kerr) applied with and without adhesive system (Optibond Solo Plus, Kerr) were combined with three different surface treatments (Hydrofluoric Acid Etching, Sandblasting, combination of both) for repairing feldspathic ceramics. Two commercial systems for ceramic repairing were tested as controls (Porcelain Repair Kit, Ultradent, and CoJet System, 3M). SBSt was performed and failure mode was evaluated using a digital microscope. A One-Way ANOVA (Tukey test for post hoc) was applied to the SBSt data and the Fisher's Exact Test was applied to the failure analysis data. RESULTS. The use of resin systems containing bi-functional phosphate monomers combined with hydrofluoric acid etching of the ceramic surface gave the highest values in terms of bond strength and of more favorable failure modalities. CONCLUSION. The simplified repairing method based on self-adhering flowable resin combined with the use of hydrofluoric acid etching showed high bond strength values and a favorable failure mode. Repairing of ceramic chipping with a self-adhering flowable resin associated with hydrofluoric acid etching showed high bond strength with a less time consuming and technique-sensitive procedure compared to standard procedure.

Thermal Stability of Grubbs' Catalyst and Its Reactivity with Self-healing Agents (Grubbs' Catalyst의 열안정성 및 자가치료제와의 반응성 평가)

  • Yoon, Sung Ho;Shi, Ya Long;Feng, Jun;Jang, Se Yong
    • Composites Research
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    • v.28 no.6
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    • pp.395-401
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    • 2015
  • This study investigated the thermal stability of Grubbs' catalyst and its reactivity with self-healing agents for self-healing damage repair. Four types of Grubbs' catalyst supplied by manufacturers were considered and each catalyst was tested in as-received and grinded conditions. Four types of self-healing agents were prepared by varying the mixing ratio of dicyclopentadiene (DCPD) and 5-ethylidene-2-norbonene (ENB). Heat flows as a function of temperature were measured through a differential scanning calorimetry (DSC) to determine the thermal stability of catalysts. Reaction heats of self-healing agents with the catalyst were measured to evaluate the reactivity of the catalyst. For this evaluation, Fluka Chemika Grubbs' catalyst was used based on the maximum temperature and the time to reach the maximum temperature. According to the results, catalysts had different shapes depending on the manufacturer and the results showed that the smaller the size of the catalyst the higher the reactivity with self-healing agents. As the ENB ratio in self-healing agents increased, the maximum temperature increased, and the time to reach the maximum temperature decreased. As the amount of the catalyst increased, the maximum temperature increased, and the time to reach the maximum temperature decreased. Considering the thermal stability of the catalyst and its reactivity with the self-healing agent, combination of 0.5 wt% catalyst and the D3E1 self-healing agent was optimal for self-healing damage repair. Finally, as the thermal decomposition may occur depending on the environmental temperature, the catalyst must not be exposed to temperature higher than that is necessary to maintain the thermal stability of the catalyst.

Study on the injecting technology of waterproofing layer for water leakage repair of roof (건축물 옥상방수층의 누수보수를 위한 방수층재형성 주입기술에 관한 연구)

  • 배기선;조일규;장혁수;곽규성
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2002.11a
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    • pp.23-27
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    • 2002
  • Waterproofing is one of the important factor to improve performance of building elements. But existing repair system for waterproofing have many problems like a damage of waterproof layer due to movement of concrete substrate, blistering effect and moisture condition. So waterproofing layer can not play an important part to improve waterproofing function and performance of building. Therefore, new waterproofing system to solve these problems of existing waterproofing system is developed. In this paper, new waterproofing system in water-leakage repair for remodeling is introduced

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Examination of Applicability of Repair Mortar using Very High Early Strength Cement (초속경시멘트를 이용한 보수모르터의 현장적용성 검토)

  • Jeon Jin Hwan;Kasai Hiroshi;Yazaki Hideaki;Cho Chung Ki
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.309-312
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    • 2004
  • The hydraulic structure of the hydroelectric power plant such as aqueduct tunnels and the drainage canal became old. Therefore, because the concrete surface of the aqueduct tunnel has received severe damage by wear-out and the crack etc the repair is demanded. This research examined the applicability of the repair mortar which mixed the fly ash and an artificial aggregate by using the very high early strength cement. As a result, good Quality repair mortar which satisfied the demand performance more than self-flow 270mm and compressive strength $50N/mm^2$ (age of 28days) adjusting of water cement ratio by using the MTX cement be able to be manufactured.

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Experimental investigation of thermal/mechanical characteristics to the maximal efficiency for self-healing technique (치료효율 극대화를 위한 자가치료제의 열적/기계적 특성 연구)

  • 허광수;오진오;윤성호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.626-629
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    • 2004
  • Recently, the self-healing technique is being investigated to repair the damaged polymeric composites by the use of microcapsules with the healing agent. This technique can obtains both the damage detection and the damage repair simultaneously over the converntional repairing techniques. In this study, the effects of the catalyst ratio to the healing agent and thermal characteristics to the mixtures of healing agent are investigated through single lap shear tests and DSC. The Healing agents such as DCPD, ENB, and their mixtures are considered and Grubb's catalyst is used as a catalst.

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Effects of Therapeutic Massage and Home Exercise Program on Pain, Range of Motion, Depression, and Quality of Life after Arthroscopic Rotator Cuff Repair

  • Lee, Young-Min;Kwon, Jung-Won
    • The Journal of Korean Physical Therapy
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    • v.33 no.2
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    • pp.114-121
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    • 2021
  • Purpose: This study examined the effects of therapeutic massage (TMP) and home exercise program (HEP) on pain, range of motion (ROM), depression, and quality of life (QOL) after arthroscopic rotator cuff repair in middle-aged women. Methods: Nineteen middle-aged women who underwent arthroscopic rotator cuff repair were enrolled in the study. All subjects were assigned randomly to the experimental group (n=9) or the control group (n=10). The subjects in both groups performed HEP for 30 minutes, three times per day, for eight weeks. The subjects in the experimental group also performed HEP, with TMP being performed for 30 minutes, 16 sessions for eight weeks. All subjects were evaluated with a visual analogue scale (VAS), shoulder ROM, self-rating depression scale (SDS), and Korean brief version of WHO quality of life scale (WHOQOL-BREF). A paired t-test was performed to test the significant differences between before and after the intervention. An independent t-test was conducted to test the significant differences between the groups. Results: Following the intervention, both groups showed significant differences than before the intervention in the VAS, shoulder ROM, SDS, and WHOQOL-BREF (p<0.05). There were significant differences in the ROM of shoulder flexion, SDS, and WHOQOL-BREF between the groups (p<0.05). Conclusion: These findings suggest that intensive TMP is an effective method for improving shoulder flexion mobility, depressive symptom, and QOL in middle-aged women after arthroscopic rotator cuff repair.