• 한국보육지원학회지
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• 제19권6호
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• pp.1-19
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• 2023

Objective: The aim of the present study was to develop and validate a recognition scale for childcare teachers' rights. Methods: Statistical methods for data analysis involved the use of SPSS 20.0 and AMOS 20.0. To confirm the reliability and validity of the developed scale, various analyses, including item quality assessment, item discrimination, exploratory factor analysis, confirmatory factor analysis, and Pearson correlation analysis, were conducted. The maximum likelihood estimation method was employed for model fitting. Goodness of fit was assessed using SRMR, RMSEA and its 90% confidence interval, CFI, and TLI. Through these analyses, the scale's reliability and validity exceeded the standard. Consequently, 5 factors and 30 questions were ultimately selected as the recognition scale for childcare teachers' rights. Results: First, a recognition scale for childcare teachers' rights was developed to reflect changes in childcare settings. Second, an objective measurement was incorporated into the recognition scale of childcare teachers' rights. Third, the analysis using the proposed scale revealed a correlation between the recognition of childcare teachers' rights and life satisfaction. Conclusion/Implications: The study developed a scale capable of objectively measuring the recognition of childcare teachers' rights.

• 임상간호연구
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• 제30권1호
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• pp.11-23
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• 2024

Purpose: This study developed a scale of nurses' stress and examined the validity and reliability of the scale. Methods: The scale was developed according to DeVellis' scale development procedure. Based on the Nursing Work Environment Stress model and the results of focus group interviews, 43 preliminary items were generated. A survey was conducted with 208 clinical nurses to test the psychometric properties of the scale. Both exploratory factor analysis and confirmatory factor analysis were employed to figure out and confirm the scale's theoretical structure statistically. In addition, content, convergent, and discriminative validity were evaluated and Cronbach's α was calculated to test internal reliability. Results: The final scale consisted of 19 items and verified four-factor structures. The structure of the scale was confirmed using confirmatory factor analysis, and it showed moderate correlations with the Copenhagen Burnout Inventory and Korean Nurses Occupational Stress Scale. Cronbach's α was .87. Conclusion: A scale of nurses' stress to nursing work was developed to embrace a wide range of nurses' psychological responses to nursing work based on the theoretical model.

• Wind and Structures
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• 제34권4호
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• pp.355-369
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• 2022

Section model test, as the most commonly used method to evaluate the aerostatic and aeroelastic performances of long-span bridges, may be carried out under different conditions of incoming wind speed, geometric scale and wind tunnel facilities, which may lead to potential Reynolds number (Re) effect, model scaling effect and wind tunnel scale effect, respectively. The Re effect and scale effect on aerostatic force coefficients and aeroelastic characteristics of streamlined bridge decks were investigated via 1:100 and 1:60 scale section model tests. The influence of auxiliary facilities was further investigated by comparative tests between a bare deck section and the deck section with auxiliary facilities. The force measurement results over a Re region from about 1×10⁵ to 4×10⁵ indicate that the drag coefficients of both deck sections show obvious Re effect, while the pitching moment coefficients have weak Re dependence. The lift coefficients of the smaller scale models have more significant Re effect. Comparative tests of different scale models under the same Re number indicate that the static force coefficients have obvious scale effect, which is even more prominent than the Re effect. Additionally, the scale effect induced by lower model length to wind tunnel height ratio may produce static force coefficients with smaller absolute values, which may be less conservative for structural design. The results with respect to flutter stability indicate that the aerodynamic-damping-related flutter derivatives 𝘈^*₂ and 𝐴^*₁𝐻^*₃ have opposite scale effect, which makes the overall scale effect on critical flutter wind speed greatly weakened. The most significant scale effect on critical flutter wind speed occurs at +3° wind angle of attack, which makes the small-scale section models give conservative predictions.

• 한국산림과학회지
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• 제98권6호
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• pp.639-645
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• 2009

이 연구는 우리나라의 산악형 산림지대의 지형을 분류하기 위한 방안으로 TPI를 응용하기 위해 수행되었다. 이 방법을 적용하기 위해서는 지형특성에 적합한 기초분석단위로 scale factor들이 요구된다. 따라서 본 연구에서는 scale factor를 결정하기 위한 객관적으로 결정하기 위한 방안을 제시하였다. 즉, 산지의 기복 패턴를 반영하기 위한 scale factor를 결정하기 위해 음영기복도를 이용하여 제작된 지형성장곡선으로부터 기울기변화도 곡선을 작성하였다. 기울기변화도 곡선을 이용하여 기복의 변화량이 최대가 되는 지점을 찾고, 그 극대점에서의 grid 크기를 찾아 지형 분류를 위한 scale factor로 결정하였다. scale factor 결정 알고리즘의 적용성을 검토하기 위하여 지형특성이 다른 3곳의 산악지대에 대한 scale factor를 도출하고, 지형분류를 수행하였다. 이 방법에 따른 연구결과 scale factor는 지형기복이 심할수록 짧아지는 경향이 있음을 보여주었다. 또한 TPI를 이용하여 분류한 능선과 계곡의 수가 종단면도를 이용한 방법과 유사하게 나타났고, scale factor의 크기가 대상지역의 능선 간 평균거리와 일치하는 경향이 있음을 보여주었다.

• 미생물과산업
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• 제16권2호
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• pp.49-52
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• 1990

발효공업이 발달되면서 발효조의 scale-up에 대한 문제는 꾸준하게 연구되어져 왔다. 이 scale-up은 미생물 뿐만 아니라 최근에는 동물이나 식물 그리고 곤충세포의 대량배양을 위해서도 계속적으로 연구되고 있는 분야이다. 수많은 생물반응기가 개발되었고 또 개발중에 있는데, 각 반응기에 대한 scale-up의 방법은 서로 상이할 수 있기 때문에 본 고에서는 현재 산업계에서 가장 많이 사용되고 있는 전통적인 교반조 발효기에 대한 scale-up의 원리와 응용을 다루고자 한다.

• Tribology and Lubricants
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• 제21권5호
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• pp.209-215
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• 2005

Nano/micro friction with the contact area was studied on Si-wafer (100) and diamond-like carbon (DLC) film. Borosilicate balls of radii $0.32{\mu}m,\;0.5{\mu}m,\;1.25{\mu}m\;and\;2.5{\mu}m$ mounted on the top of AFM tip (NPS) were used for nano-scale contact and Soda Lime glass balls of radii 0.25mm, 0.5mm, 1mm were used for micro-scale contact. At nano-scale, the friction between ball and surface was measured with the applied normal load using an atomic force microscope (AFM), and at micro scale it was measured using ball-on flat type micro-tribotester. All the experiments were conducted at controlled conditions of temperature $(24\pm1^{\circ}C)$ and humidity $(45\pm5\%)$. Friction was measured as a function of applied normal load in the range of 0-160nN at nano scale and in the range of $1000{\mu}N,\; 1500{\mu}N,\;3000{\mu}N\;and\;4800{\mu}N$ at micro scale. Results showed that the friction at nano scale increased with the applied normal load and ball size for both kinds of samples. Similar behavior of friction with the applied normal load and ball size was observed for Si-wafer at micro scale. However, for DLC friction decreased with the ball size. This difference of in behavior of friction in DLC nano- and microscale was attribute to the difference in the operating mechanisms. The evidence of the operating mechanisms at micro-scale were observed using scanning electron microscope (SEM). At micro-scale, solid-solid adhesion was dominant in Silicon-wafer, while plowing in DLC. Contrary to the nano scale that shows almost a wear-less situation, wear was prominent at micro-scale. At nano- and micro-scale, effect of contact area on the friction was discussed with the different applied normal load and ball size.

• 한국물환경학회지
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• 제34권2호
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• pp.226-233
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• 2018

Small-scale wastewater discharge facilities account for 98% of all workplaces, but in the generation and emission of major pollutants, they account for 27.5 % and 23.5 %, respectively. Since the proportion of the emission load of the small-scale workplace is not large, the national environmental policy has been established mainly around large-scale wastewater discharge facilities. However, in the case of specific hazardous substances in water, the amount of the discharge load of the small-scale wastewater discharge facility was 2.4 times higher than that of the generation load. Certain types of specific hazardous substances in water, which have a higher discharge load than large-scale wastewater discharge facilities, account for 24 ~ 32 %. There are also cases in which the discharge load from a small-scale discharge facility is more than four times higher, depending on the specific kind of water pollutant. As a result of inspections, the violation rate of the small-scale wastewater discharge facility among the total violations by facilities is 93.9 ~ 97.5 %. As a result, the ecotoxicity value of small-scale wastewater discharge facilities was high in most industries, and there was a fluctuation in the measured value. This indicates that the ecological integrity of the water system can be largely influenced by small-scale wastewater discharge facilities. Therefore, it is necessary to expand the environmental management of small-scale wastewater discharge facilities, and in some cases, the effect of the improvement in quality may be more significant than in the management of large-scale wastewater discharge facilities.

• 건축역사연구
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• 제16권4호
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• pp.95-110
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• 2007

In spite of the increasing significance on a scale of building measurement unit and its system having been used in many areas of architecture, only a few researchers carried out the studies on a specific period. It is even harder to find a research results dealt in view of architecture. This research gives a focus on different types of scales employed in the ancient buildings and their sites, based on the research results of unit scale or scales found in recent excavations. After the review of literature on the scales widely used in the ancient times and of the various types of scales excavated archeologically, a kind of scale unit system that had been widely and extensively employed throughout the period of 'Three Kingdoms' could be revealed. The scale system is possibly able to be applied to estimate the exact scale of buildings and their sites as well in that era. The research results show that the scale and its system employed in the East and West buildings and their sites of 'Kum-dang' in 'Mi-ruk Sa' temple are different from 'Kokuryo' scale that was believed in to be used in the temple. Contrary to the suggestion by excavation report on the type of scale employed in the buildings their sites, a scale of 29 centimeters, similar to that of Tang, was employed. It was also found that one module consists of three 'Chuk's of 88.8 centimeters. Based on this scale system, we could conclude that three modules of the buildings on the front and two and half modules of them on the sides were explained by this scale and its system.

• 한국사회복지학
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• 제59권4호
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• pp.273-296
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• 2007

본 연구는 장애정체감을 평가하는 도구로 개발된 23문항의 척도를 Rasch 모형을 적용하여 문항을 재구성한 연구이다. 척수손상 장애인 397명을 대상으로 개발한 장애정체감 척도(이익섭 신은경, 2006)는 요인분석으로 타당도를 검증한 것으로 문항의 적합도나 난이도 및 응답범주의 적절성을 평가하지는 못하였다. 본 연구에서는 요인분석 절차에서 파생될 수 있는 한계를 보완하고자 문항반응이론(item response theory)의 하나인 Rasch 모형을 각 하위차원별로 적용하여 장애정체감 척도를 재검토하였다. 결과로는 4개차원의 20문항으로 축소되는 것이 문항의 적합도가 높은 것으로 나타났으며, 문항의 난이도 측면에서는 평균수준의 문항이 많은 것으로 드러났다. 응답범주는 4점 척도가 적절했다고 평가되었다. 이러한 척도의 재구성을 통하여 장애정체감의 문항 적합도와 난이도 및 응답범주의 적절성을 객관적으로 평가할 수 있었다.

• Nuclear Engineering and Technology
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• 제42권6호
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• pp.620-635
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• 2010

In this paper we describe current activities on the project Multi-Scale Modeling and Analysis of convective boiling (MSMA), conducted jointly by the Paul Scherrer Institute (PSI) and the Swiss Nuclear Utilities (Swissnuclear). The long-term aim of the MSMA project is to formulate improved closure laws for Computational Fluid Dynamics (CFD) simulations for prediction of convective boiling and eventually of the Critical Heat Flux (CHF). As boiling is controlled by the competition of numerous phenomena at various length and time scales, a multi-scale approach is employed to tackle the problem at different scales. In the MSMA project, the scales on which we focus range from the CFD scale (macro-scale), bubble size scale (meso-scale), liquid micro-layer and triple interline scale (micro-scale), and molecular scale (nano-scale). The current focus of the project is on micro- and meso-scales modeling. The numerical framework comprises a highly efficient, parallel DNS solver, the PSI-BOIL code. The code has incorporated an Immersed Boundary Method (IBM) to tackle complex geometries. For simulation of meso-scales (bubbles), we use the Constrained Interpolation Profile method: Conservative Semi-Lagrangian $2^{nd}$ order (CIP-CSL2). The phase change is described either by applying conventional jump conditions at the interface, or by using the Phase Field (PF) approach. In this work, we present selected results for flows in complex geometry using the IBM, selected bubbly flow simulations using the CIP-CSL2 method and results for phase change using the PF approach. In the subsequent stage of the project, the importance of effects of nano-scale processes on the global boiling heat transfer will be evaluated. To validate the models, more experimental information will be needed in the future, so it is expected that the MSMA project will become the seed for a long-term, combined theoretical and experimental program.