• 한국과학교육학회지
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• 제43권1호
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• pp.29-36
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• 2023

이 연구에서는 과학 체험 프로그램의 운영이 예비교사의 과학적 소양에 미치는 영향을 과학문화소양과 핵심역량을 중심으로 알아보았다. K대학교 255명의 예비교사가 참여하였으며, 과학문화소양은 단일집단 사전-사후검사 설계로 대응표본 t-검정을 통해 프로그램의 효과를 알아보았다. 핵심역량 성장 인식은 사후검사만 실시하였으며, ANOVA로 역량별 성장 인식의 차이를 비교하였다. 연구 결과, 과학 문화소양에서 예비교사의 과학문화소양은 사전검사에 비해 사후검사 평균이 더 높았으며, 이 차이는 통계적으로 유의미하였다(p<.05). 핵심역량의 성장 인식 분석 결과, 과학적 의사소통 능력에서 70.6%의 예비교사가 성장을 보고하였으며, LSD로 사후검증 결과 다른 핵심역량에 비해 통계적으로 유의미하게 높은 빈도를 보였다(p<.05). 이를 통해 예비교사의 과학적 소양 함양을 위한 방안으로 과학 체험 프로그램의 교육적 가치를 확인할 수 있었다.

• 경영과학
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• 제26권3호
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• pp.79-100
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• 2009

Recently, most tech-based products are of multiple generations, since new-generation products are replacing the older ones as technologies continue to improve. Although, this means that research is needed to examine as much about the role of post-adoption behavior as the missing link between the adoptions of successive generation as first adoption of innovation, there is a dearth of literature explicitly examining consumers' post-adoption behavior, especially in the context of subscription-based service. For the subscription-based services, in spite of the important role of consumer satisfaction, research on the post-adoption behavior can not carefully examine the direct impact of consumer satisfaction on their decision to upgrade by considering usage instead of satisfaction as the missing link between buyers' first adoption and their next-generation adoption. This study identified two types of attribute satisfaction such as basic attribute and core attribute using both literature review and FGI (Focus Group Interview), and tries to investigate how two types of attribute satisfaction has influence on customers' intention to upgrade to the next-generation services. and a moderating role of customer loyalty between attribute satisfaction and intention. The empirical results show that core-attribute satisfaction has a negative influence on customers' intention to upgrade, due to the moderating role of customer loyalty, but it can raise their intention to upgrade next-generation services. However, basic-attribute satisfaction, on the other hand, appears to positively influence both customer loyalty and the intention to upgrade. We also find that the consumer attribute satisfaction is influenced by consumer innovativeness, her perception of service and the usage of each features' type in different ways. Finally, academic and practical implication is made, limitation is clarified and a direction for further studies is suggested.

• Restorative Dentistry and Endodontics
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• 제45권4호
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• pp.49.1-49.11
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• 2020

Objectives: The aim of this study was to perform a clinical and radiographic analysis of endodontically treated teeth (ETT) restored with cast metal posts (CMPs) or prefabricated glass fiber posts (GFPs) and crowns. Materials and Methods: Fifty ETT were restored with 25 CMPs and 25 GFPs at a private dental clinic between 2001 and 2016. The restorations consisted of 12 all-ceramic crowns, 31 metal-ceramic crowns, and 7 composite resin crowns. Demographic data, type of teeth, type of post-and-core system, time of placement, crown restorations, the number of proximal contacts, the type of antagonist, and reports of any complications after post-and-core placement were recorded for each patient. Assessments were performed at baseline (radiographic) and follow-up (radiographic and clinical). Data were analyzed by the McNemar test, the Pearson χ² test, and Kaplan-Meier survival curves (α = 0.05). The mean follow-up was 67.6 months. Results: No significant difference was observed for any of the radiographic parameters when the baseline and final radiographs were compared. In the clinical evaluation, anatomical form (p = 0.009) and occlusion (p = 0.001) showed significant differences according to the type of crown restoration; specifically, metal-ceramic and all-ceramic crowns outperformed composite resin crowns. Conclusions: CMPs and GFPs showed favorable results for restoring ETT after 6 years of follow-up. All-ceramic and metal-ceramic crowns showed higher survival rates and better clinical outcomes.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.15-16
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• 2023

In this paper, we aimed to develop a new method for diagnosing the depth of neutralization in architectural and civil engineering structures using the core drilling method, which combines the speed of drilling with the accuracy of core ringing. When compared to the drilling method, the core drilling method showed a lower measurement deviation of 1-2mm (7.6%) in confirming the depth of neutralization. This is believed to be a result of potential interference during the sample collection process in the drilling method, where the drill may pass through aggregates, leading to overestimation, as indicated in previous studies. The rapid evaluation of neutralization using the core drilling method serves as an alternative to address the issues associated with both drilling and core ringing methods in diagnosing the depth of neutralization. It offers a solution to the inaccuracy caused by coarse aggregates and the cumbersome post-processing steps required for neutralization diagnosis. Our proposed technique aims to provide an accurate and expedited diagnosis of neutralization depth without the need for additional processes.

• Journal of Biosystems Engineering
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• 제29권2호
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• pp.187-194
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• 2004

The study focused on setting priority among the future core technologies that were derived by Delphi in agricultural management ＆ information using analytic hierarchy process(AHP). Items for setting priority were decided as ‘technology’, ‘market’, and ‘public concerns’by council. The future core technologies were divided into four parts by importance and R＆D level. Technologies which consisted of upper two parts having higher importance were considered in the study. Questionnaires were given to 9 specialists in biosystems engineering. As the results, ‘market’ was decided as a most important item. The most important technologies were ‘Developing technology and system of post harvest processing for higher quality rice’ in group I, and ‘Developing sensor technology to evaluate quality and safety for agricultural products’ in group II.

• 대한치과보철학회지
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• 제41권2호
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• pp.232-242
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• 2003

Statement of problem : Fiber-reinforced posts have lower modulus of elasticity than titanium post or cast post-core. With this similar elasticity to that of dentin, fiber-reinforced posts have been known to have a tendency to reduce the risk of root fracture. However, there were few studies on the teeth restored with fiber-reinforced posts under the condition of reduced periodontal support. Purpose : The purpose of this study was to evaluate the fracture strength and failure mode of endodontically treated teeth restored with fiber-reinforced posts and titanium posts under the condition of reduced periodontal support. Material and method : Extracted human maxillary incisor roots were divided into 3 groups (group 1 carbon fiber post, group 2 : glass fiber post, and group 3 : titanium alloy post). After coronectomy and endodontic treatment, teeth were restored with each post systems and resin core according to the manufacturer's recommendation. Then, teeth with simulated periodontal ligament were embedded in the acrylic resin blocks at the level of 4 mm below the cemento-enamel junction. Each specimen was exposed to $10^5$ load cycles with average 30 N force in $36.5^{\circ}C$ water using a computer-controlled chewing simulator. Loads were applied at $45^{\circ}$ angle to the long axis of the teeth. After cyclic loading, teeth were subjected a compressive load until failure at a crosshead speed of 0.5 mm/min. Fracture strength (N) and failure mode were examined. The fracture strength was analyzed with one-way ANOVA and the Scheffe adjustment at the 95% significance level. Results and conclusion : The results were as follows. 1. There was no statistically significant difference in the mean fracture strength among the groups (P<.05). 2. Carbon fiber post and glass fiber post group showed less root fracture tendency than control group. 3. All specimens with root fractures showed fracture lines above the level of acrylic resin block, except for only one specimen in group 3.

• 전자통신동향분석
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• 제38권6호
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• pp.128-136
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• 2023

Lithium accounts for only 0.0017% of the earth crust, and it is produced in geographically limited regions such as South America, the United States, and China. Since the first half of 2017, the price of lithium has been continuously increasing, and with the rapid adoption of electric vehicles, lithium resources are expected to be depleted in the near future. In addition, economic blocs worldwide face intensifying scenarios such as competition for technological supremacy and protectionism of domestic industries. Consequently, Korea is deepening its dependence on China for core materials and is vulnerable to the influence of the United States Inflation Reduction Act. We analyze post-lithium secondary battery technologies that rely on more earth-abundant elements to replace lithium, whose production is limited to specific regions. Specifically, we focus on the technological status and issues of sodium-ion, zinc-air, and redox-flow batteries. In addition, research trends in post-lithium secondary batteries are examined. Post-lithium secondary batteries seem promising for large-capacity energy storage systems while reducing the costs of raw materials compared with existing lithium-based technologies.

• 기본간호학회지
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• 제21권3호
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• pp.292-301
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• 2014

Purpose: The purpose of this study was to contribute to the development of efficient methods of nursing practice education by evaluating effects of core fundamental nursing skills education on self-efficacy, clinical competence and practice satisfaction in nursing students. Method: The research design was a one group pretest-posttest design and it was done to assess changes in self-efficacy and clinical competence from pre to the post-test which was given after the core fundamental nursing skills education was completed. Data were collected from September 5 to December 20, 2013 from 156 nursing students who were taking the 12-hours core fundamental nursing skills education at one university in Gyeonggi-do. This practicum was composed of 6 core fundamental nursing skills. Results: Self-efficacy and clinical competence scores improved. There was no significant difference in self-efficacy but there was a significant difference of clinical competence. In the subscales of clinical competence, the domain of nursing skill was scored the highest. The score for practice satisfaction was also high. Conclusion: The results indicate that the core fundamental nursing skills education is effective in improving clinical competence and practice satisfaction in nursing students. But new strategies are needed to improve self-efficacy.

• Earthquakes and Structures
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• 제10권3호
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• pp.699-716
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• 2016

Buckling-restrained braced frames (BRBFs) are commonly used as lateral force-resisting systems in the structures located in seismic-active regions. The nearly symmetric load-displacement behavior of buckling-restrained braces (BRBs) helps in dissipating the input seismic energy through metallic hysteresis. In this study, an experimental investigation has been conducted on the reduced-core length BRB (RCLBRB) specimens to evaluate their hysteretic and overall performance under gradually increased cyclic loading. Detachable casings are used for the concrete providing confinement to the steel core segments of all test specimens to facilitate the post-earthquake inspection of steel core elements. The influence of variable core clearance and the local detailing of casings on the cyclic performance of RCLBRB specimens has been studied. The RCLBRB specimen with the detachable casing system and a smaller core clearance at the end zone as compared to the central region exhibited excellent hysteretic behavior without any slip. Such RCLBRB showed balanced higher yielding deformed configuration up to a core strain of 4.2% without any premature instability. The strength-adjustment factors for the RCLBRB specimens are found to be nearly same as that of the conventional BRBs as noticed in the past studies. Simple expressions have been proposed based on the regression analysis to estimate the strength-adjustment factors and equivalent damping potential of the RCLBRB specimens.

• 대한소아치과학회지
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• 제46권1호
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• pp.111-118
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• 2019

구치 근관 치료의 임상적 성공은 근관 치료 후 수복에 의해 결정된다. 다양한 방법들이 근관 치료된 구치를 수복하기 위해 제안되고 있다. 소아청소년치과학 영역에서 근관 치료가 필요한 맹출 진행 중인 영구 구치의 전통적인 포스트 코어 및 전장관 수복은 어려움이 많고 과도한 치질 삭제를 유발한다. 치수강을 통한 적절한 유지력이 제공된다면 엔도크라운(Endocrown)은 보존적이고 심미적인 대안이 될 수 있다. 치아 형성은 크라운-코어 일체형의 수복물을 구성하기 위해 치은연과 같은 높이의 버트 조인트(butt-joint) 변연과 치수강 내부 전체의 유지 와동으로 이루어진다. 이 증례 보고는 광범위하게 손상된 부분 맹출된 제1대구치의 엔도크라운을 통한 심미적이고 보존적인 수복의 결과를 기술하고 있다.