• Restorative Dentistry and Endodontics
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• 제41권2호
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• pp.106-113
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• 2016

Objectives: This study evaluated the effects of different surface conditioning methods on the bond strength of orthodontic brackets to glazed full-zirconia surfaces. Materials and Methods: Glazed zirconia (except for the control, Zirkonzahn Prettau) disc surfaces were pre-treated: PO (control), polishing; BR, bur roughening; PP, cleaning with a prophy cup and pumice; HF, hydrofluoric acid etching; AA, air abrasion with aluminum oxide; CJ, CoJet-Sand. The surfaces were examined using profilometry, scanning electron microscopy, and electron dispersive spectroscopy. A zirconia primer (Z-Prime Plus, Z) or a silane primer (Monobond-S, S) was then applied to the surfaces, yielding 7 groups (PO-Z, BR-Z, PP-S, HF-S, AA-S, AA-Z, and CJ-S). Metal bracket-bonded specimens were stored in water for 24 hr at $37^{\circ}C$, and thermocycled for 1,000 cycles. Their bond strengths were measured using the wire loop method (n = 10). Results: Except for BR, the surface pre-treatments failed to expose the zirconia substructure. A significant difference in bond strengths was found between AA-Z ($4.60{\pm}1.08MPa$) and all other groups ($13.38{\pm}2.57-15.78{\pm}2.39MPa$, p < 0.05). For AA-Z, most of the adhesive remained on the bracket. Conclusions: For bracket bonding to glazed zirconia, a simple application of silane to the cleaned surface is recommended. A zirconia primer should be used only when the zirconia substructure is definitely exposed.

• Restorative Dentistry and Endodontics
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• 제40권2호
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• pp.136-142
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• 2015

Objectives: The aim of this study was to evaluate the effects of tri-antibiotic paste (TAP) on microtensile bond strengths (MTBS) of dental adhesives to dentin. Materials and Methods: Sixty extracted molars had their occlusal surfaces flattened to expose dentin. They were divided into two groups, i.e., control group with no dentin treatment and experimental group with dentin treatment with TAP. After 10 days, specimens were bonded using self-etch (Filtek P90 adhesive) or etch-and-rinse (Adper Single Bond Plus) adhesives and restored with composite resin. Teeth were sectioned into beams, and the specimens were subjected to MTBS test. Data were analyzed using two-way ANOVA and post hoc Tukey tests. Results: There was a statistically significant interaction between dentin treatment and adhesive on MTBS to coronal dentin (p = 0.003). Despite a trend towards worse MTBS being noticed in the experimental groups, TAP application showed no significant effect on MTBS (p = 0.064). Conclusions: The etch-and-rinse adhesive Adper Single Bond Plus presented higher mean bond strengths than the self-etch adhesive Filtek P90, irrespective of the group. The superior bond performance for Adper Single Bond when compared to Filtek P90 adhesive was confirmed by a fewer number of adhesive failures. The influence of TAP in bond strength is insignificant.

• 한국운동역학회지
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• 제26권4호
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• pp.433-441
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• 2016

Objective: The purpose of this study was to understand the injury mechanism and to provide quantitative data to use in prevention or posture correction training by conducting kinematic and kinetic analyses of risk factors of lower extremity joint injury depending on the change of direction at different angles after a landing motion. Method: This study included 11 men in their twenties (age: $24.6{\pm}1.7years$, height: $176.6{\pm}4.4cm$, weight: $71.3{\pm}8.0kg$) who were right-leg dominant. By using seven infrared cameras (Oqus 300, Qualisys, Sweden), one force platform (AMTI, USA), and an accelerometer (Noraxon, USA), single-leg drop landing was performed at a height of 30 cm. The joint range of motion (ROM) of the lower extremity, peak joint moment, peak joint power, peak vertical ground reaction force (GRF), and peak vertical acceleration were measured. For statistical analysis, one-way repeated-measures analysis of variance was conducted at a significance level of ${\alpha}$ <.05. Results: Ankle and knee joint ROM in the sagittal plane significantly differed, respectively (F = 3.145, p = .024; F = 14.183, p = .000), depending on the change of direction. However, no significant differences were observed in the ROM of ankle and knee joint in the transverse plane. Significant differences in peak joint moment were also observed but no statistically significant differences were found in negative joint power between the conditions. Peak vertical GRF was high in landing (LAD) and after landing, left $45^{\circ}$ cutting (LLC), with a significant difference (F = 9.363, p = .000). The peak vertical acceleration was relatively high in LAD and LLC compared with other conditions, but the difference was not significant. Conclusion: We conclude that moving in the left direction may expose athletes to greater injury risk in terms of joint kinetics than moving in the right direction. However, further investigation of joint injury mechanisms in sports would be required to confirm these findings.

• Journal of Chest Surgery
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• 제48권1호
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• pp.13-24
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• 2015

Background: Controversy persists regarding the use of coronary endarterectomy (CE) in patients with severe coronary artery disease. We compared the comorbidities and perioperative characteristics of patients undergoing coronary artery bypass grafting (CABG) with and without CE. Methods: This study was performed in two private hospitals in Shiraz, Iran from May 2010 to December 2011 on 967 patients who underwent CABG without CE and 84 patients who underwent CABG with CE (the CE+ group). After follow-up at $9.66{\pm}3.65$ months post-surgery, 28 patients from the CE+ group underwent angiography to evaluate the patency of grafts and native coronary vessels. Results: Patients in the CE+ group had a more prevalent history of diabetes (48% vs. 36%) and number of diseased vessels ($2.88{\pm}0.39$ vs. $2.70{\pm}0.85$). The overall hospital mortality was 1.8%, and no significant difference was observed between the two groups. In the 28 patients who underwent reangiography, 113 vessels were bypassed and 29 endarterectomies were performed, mostly on the left anterior descending artery (12 endarterectomies) and the right coronary artery (8 endarterectomies). In the endarterectomized vessels, a 66% patency rate was found in both the grafts and the native vessels. The native coronary vessels were more likely to be patent when the left internal mammary artery was used as a conduit than when a saphenous vein bypass graft was used. Conclusion: The lack of a significant difference in postoperative complications in patients who underwent CABG with or without CE may indicate that CE does not expose patients to a higher risk of complications. Since most of the endarterectomized vessels were shown to be patent during the follow-up period, we propose that endarterectomy is a viable option for patients with severely diseased vessels.

• 한국임상수의학회지
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• 제34권2호
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• pp.108-111
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• 2017

A 4-year-old, weighing 7.6 kg, castrated male, Pug presented with ingestion of gastric cavity foreign body. Physical examination revealed panting, retching and hyper-salivation. Blood chemistry and complete blood cell count were normal, but hypophosphatemia was observed. An abdominal radiograph revealed the foreign body (FB), round shape and 2 cm length, at the pyloric region of stomach. A thoracic radiograph revealed an incidental metal FB, 3.5 cm length, at the cranial portion of the diaphragm. An upper gastrointestinal endoscopy was performed to remove the FB in the stomach and then a peach-pit was removed. However the metal FB was not found in the esophagus therefore a lateral thoracotomy was performed. A right lateral thoracotomy through the $7^{th}$ intercostal space was accomplished to expose the right caudal lung lobe. After open the thoracic cavity, foreign body was not observed by gross evaluation and caudal lung lobe was attached to the diaphragm. The FB was identified inside the lung lobe and surrounded by granulation tissue. The metal FB (sewing needle) was removed with blunt dissection and incised lung lobe was sutured using absorbable suture material PDS 4-0 with interrupted suture. A thoracotomy tube was inserted into the thoracic cavity during surgery. Patient's respiration became stable after surgery. A chest tube was removed 3 days after surgery. No complications were noted and the dog was discharged 4 days after surgery. In small animal, foreign body ingestion is a common reason for emergency. After ingestion of the FB, perforation through the esophagus and migration to inside the lung lobe is not common in small animals. In this case, thoracic metal FB was identified incidentally and removal of a thoracic FB with thoracotomy was performed successfully.

• Mycobiology
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• 제36권3호
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• pp.143-147
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• 2008

We have detected the slime mold, Diachea leucopodia (GNU06-10) in a strawberry greenhouse located in Sancheong-gun, Gyeongnam. Typical fruiting bodies had developed gregariously on the strawberry leaves, petioles, and plant debris on ground soil habitat, and also surprisingly on plastic pipes and a vinyl covering. Field samples were examined via stereomicroscopy, light microscopy, and SEM for the determination of morphological characteristics. Dark-brown to black spores formed gregariously within the stipitate cylindrical sporangium, and were covered by an iridescent peridium, which may be intact at maturity, or may have disintegrated. The upper portion of the peridium generally breaks up to expose the spores, whereas the lower portion was usually persistent. The results of energy dispersive X-ray spectrometer (EDS) analysis showed that lime was present in the stalk and columella but absent from the spores, capillitium, and peridium. The above characteristics confirm its taxonomic position in the genus Diachea. However, this genus is intermediate in character between the Physarales and Stemonitales of the Myxogastromycetidae. Hence, this genus had been classified as a member of the Stemonitales until the mid-1970's, on the basis of its iridescent peridium and noncalcareous capillitial system, similar to Comatricha of the Stemonitaceae. By way of contrast, emphasis on morphological characteristics, most notably the calcareous stalk and typical columella, places Diachea within the order Physarales. The presence of a phaneroplasmodium during the trophic stage and lime deposition in its sporophores, as was confirmed in this work, supported the inclusion of Diachea in the Physarales, and the noncalcareous capillitial system verified its identification as a member of the Didymiaceae. Further characteristics of the species D. leucopodia include the following: phaneroplasmodium, spore globose 7.5 ${\mu}m$ in diameter, very minutely roughened; sporangia $500{\mu}m\times1mm$, more or less cylindrical, gregarious, stalked 1.2mm; stalk and columella white.

• 한국멀티미디어학회논문지
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• 제16권3호
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• pp.330-335
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• 2013

차량 간 통신 기술을 적용한 차량의 안전 시스템은 시시각각 변하는 정보를 주변 차량으로 신속히 전파될 수 있기 때문에 사고 발생 위험 최소화 및 추돌 사고의 확산을 방지할 수 있을 것으로 기대된다. 현재 차량간 통신 지원을 위해 IEEE 802.11 DCF 기반 Flooding 기법을 활용한 정보 전달 기술을 활용하는 방안이 제시되고 있지만, 차량 밀도가 높아짐에 따라 Broadcasting 메시지 빈도에 의해 추가적인 연쇄 추돌 현상 발생 확률 증가라는 문제점이 제시되고 있다. 따라서, 본 논문에서는 연쇄 추돌 방지를 위한 V2V 통신 기반의 사고 알림 Broadcasting 기술을 제시하며, 이는 사고 발생 시 각 차량의 정량적 우선순위에 의거하여 공유채널의 선점 권리를 자동적으로 부여하여 인접 지역으로 위험 메시지를 신속하게 전파하는 방법을 제안한다. 또한, 제안 방안의 성능 검증을 위해 시뮬레이션을 통해 기존 Flooding 기반 방안과의 비교 분석을 수행한다.

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.468-476
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• 1998

The purpose of this study was to observe the morphologic change of dentinal surface, adhesion in interface between dentin and bonding agents, and penetration pattern of resin tags into dentinal tubles according to bonding procedure of ONE-STEP universal adhesive system. Ten extracted human molars were mounted in dental stone and sectioned to expose mid-coronal occlusal dentin and again sectioned tooth crown apically. Specimens were randomly assigned to three groups for dentin conditioning with 32% phoshoric acid, two coats of bonding agents after dentin conditioning, and bond of composite resin. The surfaces of dentin were treated with etch ant and applied bonding agent, and bonded composite resin according to the directions of manufacturer. Specimens which were boned composite were sectioned longitudinally for observing interfaces between resin and dentin. Two of specimens which were sectioned longitudinally were immersed in 6 N HCL for 30 seconds and 1% NaOCL for 12 hours to partially demineralize and deproteinize the dentin substrate. Each specimen was mounted on a brass stub, sputter-coated with gold and observed under SEM. The result were as follows : 1. On the dentinal surface which was conditioned with 32% phosphoric acid. the smear layer was completely removed. orifices of dentinal tubules were opened 3-$5{\mu}m$ wide. and dentinal surface was irregular. 2. On the dentinal surface which was applied ONE-STEP. bonding agent. resin particles were observed on the orifices of dentinal tubules and intertubular dentin. 3. There were close adaptation between dentin and resin and were the pattern which composite invaded into dentin. 4. 1-$3{\mu}m$-wide hybrid layer was visible in the interface between dentin and resin. 5. Long and funnel shaped resin tags were observed in demineralized specimens. and the surfaces of tags were rough.

• 정보처리학회논문지C
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• 제11C권5호
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• pp.605-612
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• 2004

모바일 IPv6 환경에서 검증되지 않은 바인딩 갱신은 MN과 CN에게 다양한 보안위협을 유발할 수 있다. 따라서 모바일 IPv6에서 바인딩 갱신 보호는 매우 중요하며 이를 위해 안전한 바인딩 갱신 프로토콜들이 제안되었다. 본 논문에서는 모바일 IPv6 환경에서 안전한 바인딩 갱신을 위한 보안 프로토콜을 제안한다. 제안 프로토콜은 Deng과 Zhou, Bao가 제안한 프로토콜에 Aura의 2중 해쉬 기반의 CGA 기법을 적용함으로써 제 3의 신뢰할 수 있는 CA(Certificate Authority)의 필요성을 제거하였다 ［2,9］. 이러한 2중 해쉬 기반의 CGA 기법을 통해 제안 프로토콜은 다른 CGA 기반의 프로토콜보다 강력한 보안성을 지원하며 동시에 기존 연구에서 제안한 프로토콜보다 적은 비용으로 HA(Home Agent)의 공개키 검증을 할 수 있다. 기존 프로토콜 및 CAH-DH, SUCV와의 비교는 제안 프로토콜이 보안성 및 성능과 관리면에서 우수함을 보인다.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.253-258
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• 2021

This study aims to expose the potential dangers of K-pop through the past and present of K-pop choreography copyrights and to suggest the need to secure digital choreography copyrights for the sustainability of K-pop considering national responsibility. As the content industry quickly sought countermeasures to digital transformation, such as the launch of K-pop platforms and the evolution of OMO (Online Merges with Offline) media commerce in response to changes in the industrial environment due to COVID-19, the annual export of the domestic content industry increased by 6.3% compared to the previous year. Accordingly, our copyright does not require that works be fixed in tangibles, as in Japan and Germany, on the basis of entrusting each country's legislation to determine whether to require fixation on choreographed works. On the other hand, the United States, France and the United Kingdom are demanding that it be fixed. Although choreography is at the center of K-pop and the value and influence of K-pop videos including cover dance through new media are discussed from various perspectives, copyright on choreography that needs to be resolved in business platforms for K-pop scalability The fact that there is such a big difference in problem perception is an area where we must not lose our vigilance. As the development of today's technology, the method of fixing a choreography looks very easy as an image, but at the same time can be stolen very quickly. Therefore, compared to overseas cases, it is urgent to improve the difference in perception of copyright registration for K-pop choreography and to supplement the system include the NFT.