• Macromolecular Research
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• 제15권3호
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• pp.225-233
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• 2007

To improve the poor mechanical and low-temperature properties of glycidyl azide polymer (GAP)-based propellants, the addition of binders was investigated using GAP and flexible polymer backbone-structural polycaprolactone (PCP) at various weight(wt) ratios, and varying the ratio of Desmodur N-100 pluriisocyanate (N-100) to isophorone diisocyanate (IPDI). Using Gee's theory, the solubility parameter of the PCP network was determined, in order to elucidate the physical and chemical interaction between GAP and PCP. The structure of the binder networks was characterized by measuring the cross-link densities and molecular weights between cross-links ($M_c$) obtained by a swelling experiment using Flory-Rhener theory. The thermal and mechanical properties of the segmented block copolyurethane (GAP-b-PCP) binders prepared by the incorporation of PCP into the binder recipes were investigated, along with the effect of the different curatives ratios.

• 한국군사과학기술학회지
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• 제10권3호
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• pp.5-15
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• 2007

A welding structures is generally composed of dissimilar steel materials in order to reduce weight cost, and has a gap to fill the welding agent. Also, heat flow analysis should be fulfilled for structure existing of gap to figure out residual stress which is generated after welding. Since mechanical properties of welding structure composed of dissimilar steel is more fragile than mechanical properties of welding structure consisted of same material, heat flow analysis verifying this should be fulfilled as well. Therefore, on this research, heat flow analysis about dissimilar steel weldment consisted of gap existing AISI304 and AISI630 is practiced so that it could be a basic data of research about mechanical properties of gap existing dissimilar steel welding part which is going to be studied later on. During heat flow analysis, heat input model which based on Gaussian profile and using volume heat flux was newly consisted and applied. In addition, for verifying of analysis on this research, gap existing dissimilar steel weldment which had gap of 0.25mm and was welded using Nd-YAG. The welding profile and temperature distribution for weldment during welding was compared to the result which was gotten through heat flow analysis. Both of those results corresponded each other.

• 대한치과보철학회지
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• 제55권2호
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• pp.135-143
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• 2017

목적: 연구의 목적은 동일한 지대치에서 각각 모델스캔 방법과 구강 내 스캔 방법으로 제작된 지르코니아 보철물의 변연 및 내면적합도를 비교하는 것이다. 재료 및 방법: 발거된 사람의 하악 제1대구치 20개에 대해 지르코니아 보철물을 위한 지대치 형성이 이루어졌다. 첫 번째 그룹에서는 모델 스캔법으로 10개의 지대치를 스캔하였고, 두 번째 그룹에서는 나머지 10개에 대해 구강 내 스캔법을 사용하였다. 각각의 데이터들은 소프트웨어 시스템으로 전송되었고 Ceramill CAD/CAM system을 이용하여 20개의 지르코니아 보철물을 제작하였다. 먼저 weight technique을 사용하여 내면 적합도를 평가하였다. 다음으로 replica technique에서는 광학현미경을 통해 변연 적합도를 평가하였다. 통계처리는 일원배치분산분석을 이용하였다. 결과: 먼저 weight technique에서 모델 스캔법으로 제작한 그룹에서 구강 내 스캔법으로 제작한 그룹에 비해 평균적인 무게 값이 낮게 나타났고, 이는 유의성이 있었다(P < .05). 또한, replica technique에서도 측정된 5개의 영역 모두에서 구강 내 스캔법으로 제작한 그룹에 비해 모델 스캔법으로 제작한 그룹에서 변연 및 내면의 gap에 대한 거리 값이 유의하게 낮게 나타났다(P < .05). 결론: 두 그룹의 방법으로 제작한 지르코니아 보철물은 모두 임상적으로 받아들여질 만한 변연 및 내면 적합성을 보였다. 하지만 모델 스캔법으로 제작한 그룹에서 구강 내 스캔법으로 제작한 그룹에 비해 높은 변연 및 내면 적합성을 보였다.

• 항공우주시스템공학회지
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• 제14권3호
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• pp.51-59
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• 2020

초소형 위성인 큐브위성의 경우 위성체의 제한적인 중량 및 부피를 고려하여 경량화 및 전기적 회로설계 측면에서 유리한 PCB 기반의 전개형 태양전지판이 폭넓게 적용되고 있으나, PCB의 낮은 두께 방향 열전도율로 인해 태양전지셀의 방열이 어려운 점이 있다. 본 논문에서 제안한 6U 큐브위성용 태양전지판은 PCB 기반의 태양전지판으로 제작되고, 판넬 외곽에 장착된 알루미늄 보강재 접속부에 열전도 패드가 적용된다. 따라서 판넬 전면부의 태양전지셀에서 방열면인 판넬 후면으로 열전달이 원활하도록 하여 PCB 적용에 따른 장점을 유지하면서도 방열성능을 극대화함으로서 태양전지셀 온도 하강에 따른 전력생성효율 향상이 가능한 장점을 갖는다. 본 연구에서 제안된 열전도 패드가 적용된 태양전지판의 열제어 측면에서의 유효성 입증을 위해 궤도 열해석을 통해 기존 PCB 태양전지판과 비교 분석을 실시하였다.

• The Journal of Advanced Prosthodontics
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• 제8권6호
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• pp.439-448
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• 2016

PURPOSE. The purposes of this study are to evaluate the internal and marginal adaptation of two widely used CAD/CAM systems and to study the effect of porcelain press veneering process on the prosthesis adaptation. MATERIALS AND METHODS. Molar of a lower jaw typodont resin model was prepared by adjusting a 1.0 mm circumferential chamfer, an occlusal reduction of 2.0 mm, and a $5^{\circ}$ convergence angle and was duplicated as an abrasion-resistant master die. The monolithic crowns and copings were fabricated with two different CAD/CAM system-Ceramil and Zirkonzahn systems. Two kinds of non-destructive analysis methods are used in this study. First, weight technique was used to determine the overall fitting accuracy. And, to evaluate internal and marginal fit of specific part, replica technique procedures were performed. RESULTS. The silicone weight for the cement space of monolithic crowns and copings manufactured with Ceramil system was significantly higher than that from Zirkonzahn system. This gap might cause the differences in the silicone weight because the prostheses were manufactured according to the recommendation of each system. Marginal discrepancies of copings made with Ceramil system were between 106 and $117{\mu}m$ and those from Zirkonzahn system were between 111 and $115{\mu}m$. Marginal discrepancies of copings made with Ceramil system were between 101 and $131{\mu}m$ and those from Zirkonzahn system were between 116 and $131{\mu}m$. CONCLUSION. Marginal discrepancy was relatively lower in Ceramil system and internal gap was smaller in Zirkonzahn system. There were significant differences in the internal gap of monolithic crown and coping among the 2 CAD/CAM systems. Marginal discrepancy produced from the 2 CAD/CAM systems were within a reported clinically acceptable range of marginal discrepancy.

• 정보화정책
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• 제31권3호
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• pp.72-87
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• 2024

코로나19 팬데믹을 기점으로 피트니스 앱 시장이 급격히 성장하였으며, 그 중 체중감량 앱 시장이 높은 비중을 차지하고 있다. 선행연구에서는 사용자들의 심리적인 특성에 대한 고려 없이 일반적인 동기부여 및 장기적인 참여 유도를 위한 디자인 요소 개발에 집중되어 있다는 한계가 있다. 따라서 본 연구는 체중 낙인이라는 사용자 특성에 초점을 맞추어, 이를 고려한 효과적인 디자인 요소로서 인공지능 유형을 제안하고자 설문 기반 실험연구를 진행하였다. 연구결과, 앱에 대한 사용자 반응은 체중낙인 인식의 정도에 따라 다르며, 체중낙인 인식에 따라 선호하는 서비스의 인공지능 유형이 다르게 나타나는 것으로 확인되었다. 본 연구 결과는 낙인을 겪는 사용자를 대상으로 다양한 인공지능 유형을 활용해 최적의 서비스를 제공할 수 있음을 시사한다. 공공 애플리케이션 설계 시, 사용자의 심리적 요구를 반영한 공감 기반 인공지능이 체중 낙인 사용자에게 더 효과적일 수 있음을 보여준다.

• 간호행정학회지
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• 제6권2호
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• pp.259-279
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• 2000

This study is a descriptive analytic research measuring nursing service quality, using SERVQUAL model, to make fundamental data and strategies for nursing service improvement. Data were collected by self-reported questionnaire from 202 patients and 142 nurses, from June 7 to 14, 1999. The reliability of instrument were adequate(Cronbach ${\alpha}=.94$). SAS program was utilized for statistical analysis of collected data. The results were as follows; 1. There was a gab between patient's expectation and perception on nursing service(Gap B). Gap D was indicated an affecting factor to decide nursing service quality. Gap C was indicated an indirect affecting factor of nursing service quality. Because it was not statistically significant in total item analysis, but in individual item analysis, 7 items were appeared statistically significant. Gap A was not a gap occurrence factor of nursing service quality. 2. Focuses of nursing service quality improvement strategies were; (1) to direct qualitative improvement of nursing service in order to correspondence patient's nursing service expectation. (2) to make nurse's service activity modified because nurse's practice were not reached patient's expectation level. (3) to need internal, external factor analysis affecting nurse's service activity. 3. Nursing service quality was decided by rather environmental inappropriateness provided nursing service than itself. Therefore, to make nursing service quality improvement, it is required to improve nursing service environment. For this, followings are required; (1) to strengthen nurse's education on lower part of nursing service satisfaction and QI activities. (2) to balance demand and supply of nursing personnel. 3) to fix computerized system for reducing other duties weight except nursing care through analysis of nursing activity. (4) to construct rational cooperating system among related departments. 4. The important parts for nursing service quality improvement were indicated as follows: (1) Gap B: 'prompt reaction', 'examination symptom before patient's complaint', 'hearted nursing service reducing patient's dissatisfaction', 'explanation goals of nursing activities', 'having special Knowledge enough', 'maintenance position comfortably', 'management of patient's physical hygiene'. (2) Gap C: 'maintenance physical safety', 'explanation about hospital rules and facilities'. (3) Gap D: 'tender, safe injection and wound care'. Because above items are mostly improved through nurse's attitude change and quality improvement, it is required to establish nursing standardization and to strengthen nurse's clinical education. As the based on above results, followings are suggested; 1. SERVQUAL model is very useful to make strategies for nursing service quality improvement because it indicates multiple factors affecting hap occurrence. 2. At individual items analysis of Gap C, statistically significant 7 items appeared higher nurse's perception level than patient's perception level on nursing service were trouble perception level on nursing service quality improvement. So. it need further research to analysis about these difference occurring factors. 3. At analysis of Gap D, it is indicated that in nursing service performance process, multiple factors lowing nursing service quality were intruded. So it needs further research to analysis what these factors are and how each factors affect on nursing performance process. 4. nursing service quality measurement is changeable according to sample select time or sampled subject's characteristics. So to develope strategy for nursing service quality improvement is based on the results of periodical analysis.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권8호
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• pp.3986-4007
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• 2016

Business analysis is a key factor of project success or failure in information systems. However, there are few studies on business analysis competencies. The objective of this paper is to identify which competencies a business analyst (BA) needs, and analyze the importance weights and priorities of business analysis competencies. Literature review yielded 6 competency dimensions and 30 competencies. Based on interviews with 12 experts and analytic hierarchy process analysis, the relative importance weight and priority of each business analysis competency were analyzed. Moreover, an importance-perception gap between stakeholders in different positions was identified. This result can be used as selection and development criteria for superior BAs that are responsible for solving business problems using information systems solutions.

• Transactions on Electrical and Electronic Materials
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• 제4권2호
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• pp.10-14
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• 2003

Flexible displays such as plastic-based liquid crystal displays (LCDs) and organic light-emitting diode displays (OLEDDs) have been researched and developed at KETI since 1997. The plastic film substrate is very weak to heat and pressure compared to glass substrate, that its fabrication process is limited to 110$^{\circ}C$ and low pressure. The ITO films were deposited on the bare plastic film substrate by rf-magnetron sputtering. Moreover, in order to maintain uniform cell gap and pressure on the plastic film substrate, we utilized newly-invented jig and fabrication process. Electro-optical characteristics were better than or equivalent to those of typical glass LCDs though it is thinner, lighter-weight, and more robust than glass LCDs.

• 지능정보연구
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• 제16권3호
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• pp.55-75
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• 2010

일반적인 순차패턴 마이닝에서는 분석 대상 데이터 집합에 포함되는 구성요소의 발생 순서만을 고려하며, 따라서 단순 순차패턴은 쉽게 찾을 수 있는 반면 실제 응용 분야에서 널리 활용될 수 있는 관심도가 큰 순차패턴을 탐색하는데 한계가 있다. 이러한 단점을 보완하기 위한 대표적인 연구 주제들 중의 하나가 가중치 순차패턴 탐색이다. 가중치 순차패턴 탐색에서는 관심도가 큰 순차패턴을 얻기 위해서 구성요소의 단순 발생 순서 뿐만 아니라 구성요소의 가중치를 추가로 고려한다. 본 논문에서는 발생 간격에 기반 한 순차패턴 가중치 부여 기법 및 이를 활용한 순차 데이터 스트림에 대한 가중치 순차패턴 탐색 방법을 제안한다. 발생 간격 기반 가중치는 사전에 정의된 별도의 가중치 정보를 필요로 하지 않으며 순차정보를 구성하는 구성요소들의 발생 간격으로부터 구해진다. 즉, 순차패턴의 가중치를 구하는데 있어서 구성요소의 발생순서와 더불어 이들의 발생 간격을 고려하며, 따라서 보다 관심도가 크고 유용한 순차패턴을 얻는데 도움이 된다. 한편, 근래 대부분의 컴퓨터 응용 분야에서는 한정적인 데이터 집합 형태가 아닌 데이터 스트림 형태로 정보를 발생시키고 있다. 이와 같은 데이터 생성 환경의 변화를 고려하여 본 논문에서는 순차 데이터 스트림을 마이닝 대상으로 고려하였다.