• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.126-129
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• 2006

AC-plasma display panels were examined before and after the aging process to analyze the effect of the aging process. The gas analysis was done to detect the impurity gases out of the MgO film and phosphor by a residual gas analyzer. There were no differences found in the components. The MgO film was analyzed to find out the effect of an ion bombardment due to discharge. The surface roughness of the MgO film was different from regional groups due to the different degree of ion bombardments. XPS analysis showed that the 8 hour aging process was not sufficient to remove $Mg(OH)_2$ and $MgCO_3$ existed on the MgO surface. Photoluminescence measurement showed the small deterioration of blue and green phosphor.

• 소성∙가공
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• 제32권5호
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• pp.239-246
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• 2023

To reduce the forming load due to the temperature drop, during the hot forging process, a reheating hot forging process design is required that to repeat heating and forging. However, if the critical strain required for recrystallization is not induced during forging and grain growth becomes dominant due to the reduction in dislocation density due to repeated heating, the mechanical properties may deteriorate. Therefore, in this study, Inconel 706 alloy was applied, and the grain refinement behavior was comparatively analyzed according to the number of reheating times and effective strain during reheating hot forging process. Reheating was carried out with a total compression rate of 40% up to 4 times. The Inconel 706 compression test specimens heated once showed finer grains as the effective strain increased due to the dynamic recrystallization phenomenon. However, as the number of heating increases, grain refinement was observed even in a low effective strain distribution of 0.43 due to static recrystallization during reheating. Moreover, grain growth occurs at a relatively low effective strain of 0.43 when the number of reheating is four or more. Therefore, it was effective to apply an effective strain of 0.43 or more during hot forging to Inconel 706 in order to induce crystallization through grain refinement and improve the properties of forged products. In addition, we could notice that up to three reheating times condition was appropriate to prevent grain growth and maintain fine grain size.

• 한국과학교육학회지
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• 제39권6호
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• pp.695-706
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• 2019

This study conducted a case study on the process-centered evaluation competency of a middle-school/high-school science teacher using Teacher's Process-centered Evaluation Competency (T-PEC) measurement tool. The case analysis shows that teacher A in a middle school represents high competency of process-centered evaluation planning and cooperative communication while the competency of utilizing process-centered evaluation results is low owing to the characteristics of non-standardized areas. Teacher B in a high school shows high level of cooperative communication competency whereas low level of process-centered evaluation execution competency because the freedom given to students is not enough during the process of evaluation. The teacher also shows very low level of utilizing process-centered evaluation results due to the lack of time and the school culture not giving feedback to the students. According to cross-case analysis, teacher A and B both represent the highest level of collaborative communication competency and the lowest level of utilization process-centered evaluation results competency. And the lack of clear criteria for process-centered evaluation leads to different understanding of process-centered evaluation between the two teachers, and teacher B shows low the level of utilizing process-centered evaluation affects results due to the students not being concerned on feedback, security problem, and the reality focusing on the university entrance examination in high schools. Based on the results, this study suggests providing clear guidelines of process-centered evaluation to teachers, introducing an application in order to solve the time-lack problem pointed out as the biggest problem of process-centered evaluation, ensuring objectivity and security about process-centered evaluation results, and building the school culture such as the expanded application of standardized areas in order to implementing process-centered evaluation.

• 한국보건간호학회지
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• 제11권2호
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• pp.121-130
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• 1997

The community health nursing process is essential in providing community health nursing service to the community. It helps to identify community health problems. to prioritize problems, to provide service. and to evaluate service results. However. it is very rare to find a study which applies the community health nursing process. This study intended to apply the community health nursing process to a urban community. The focus of the study was a community consisting of 533 families in a region of Seoul. The study process was as follows: 1) The data was collected by conducting interviews with community leaders and by collecting surveys from the people of the community. 2) The data was summarized and analyzed. 3) The community nursing diagnosis was identified. 4) The nursing diagnosis was prioritized. 5) The general and specific objectives for service were identified. 6) A specific nursing plan was set up. 7) A detailed evaluation plan was established. Four community nursing diagnoses were identified from the community. 1) The utilization rate of health center was found to be low due to lack of knowledge about the health center and low accessibility. 2) High trafic accident rate due to narrow roads. 3) High prevalence of chronic disease due to inappropriate health behavior. 4) High noise level and foul smell due to inappropriate waste management. Among the four community nursing diagnoses. 'High prevalence of chronic diseases was identified as a priority community nursing problem. The criteria for prioritizing community nursing problems were as follows: number of people involved, fragility of clients. severity of the problem. availability. of resources. concern of the people. readiness of nurses. relevance to the national policy. This study describes the general and specific objectives to solve the high prevalence of chronic health problems. nursing plans. and an evaluation plan.

• 대한산업공학회지
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• 제28권4호
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• pp.415-424
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• 2002

Semiconductor manufacturing has been emerged as a highly competitive but profitable business. Accordingly it becomes very important for semiconductor manufacturing companies to meet customer demands at the right time, in order to keep the leading edge in the world market. However, due-date oriented production is very difficult task because of the complex job flows with highly resource conflicts in fabrication shop called FAB. Due to its cyclic manufacturing feature of products, to be completed, a semiconductor product is processed repeatedly as many times as the number of the product manufacturing cycles in FAB, and FAB processes of individual manufacturing cycles are composed with similar but not identical unit processes. In this paper, we propose a production scheduling and control scheme that is designed specifically for semiconductor scheduling environment (FAB). The proposed scheme consists of three modules: simulation module, cycle due-date estimation module, and dispatching module. The fundamental idea of the scheduler is to introduce the due-date for each cycle of job, with which the complex job flows in FAB can be controlled through a simple scheduling rule such as the minimum slack rule, such that the customer due-dates are maximally satisfied. Through detailed simulation, the performance of a cycle due-date based scheduler has been verified.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.194-198
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• 2012

In this work, we studied the microstructural changes of ITO during the annealing process. ITO nanoparticles were prepared by the sol-gel method using indium tin hydroxide as the precursor. The prepared sample was investigated using TEM, powder XRD, XPS, DRIFT, and 2D correlation analysis. The O 1s XPS spectra suggested that the microstructural changes during the annealing process are closely correlated with the oxygen sites of the ITO nanoparticles. The temperature-dependent in situ DRIFT spectra suggested that In-OH in the terminal sites is firstly decomposed and, then, Sn-O-Sn is produced in the ITO nanoparticles during the thermal annealing process. Based on the 2D correlation analysis, we deduced the following sequence of events: 1483 (due to In-OH bending mode) ${\rightarrow}$ 2268, 2164 (due to In-OH stretching mode) ${\rightarrow}$ 1546 (due to overtones of Sn-O-Sn modes) ${\rightarrow}$ 1412 (due to overtones of Sn-O-Sn modes) $cm^{-1}$.

• Journal of Magnetics
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• 제4권1호
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• pp.26-32
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• 1999

The HDDR process can be used as an effective means of processing of the coercive Nd-Fe-B-type or the Sm2Fe17Nx materials. The HDDR (hydrogenation, disproportionation, desorption, recombination) processed materials are feartured with a very fine microstructure. The thermomagnetic characteristics of the Nd-Fe-B-type or the Sm2Fe17Nx materials with fine microstructure due to the HDDR process were investigated. It has been found that the fine-microstructured hard magnetic materials showed an unusual TMA (Thermomagnetic analysis) tracting featured with a low and constant magnetization at lower temperature range and a peak just below their Curie temperatures when a low external field is applied. This thermomagnetic characteristic was immediate particularly in the TMA with a low applied field. This thermomagnetic characteristic was interpreted in terms of the competition between two counteracting effects; the decrease in magnetication due to the thermal agitation at an elevated temperature and the increase in magnetization resulting from the rotation of magnetization of the fine grains comparable to a critical single domain size due to the decreased magnetocrystalline anisotropy at an elevated temperature.

• 한국지구과학회지
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• 제43권4호
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• pp.557-566
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• 2022

The purpose of this study was to examine the status of the field application of the Science II career electives with the application of the 2015 revised curriculum up to the 3rd year of high school. This study focused on examining high school science teachers' perceptions of the student-participatory class and process-centered assessment in Science II subjects, which are career-intensive high school science electives. A total of 192 science teachers responded to the survey questionnaire, and 12 teachers participated in interviews. In the in-depth interviews conducted to supplement the survey results, questions were asked about changes in the overall class, the status of student-participatory classes, and changes in the assessment of Science II subjects due to the emphasis on process-centered assessment. The main research results included teachers' perceptions of changes in teaching and assessment methods with the application of the revised curriculum, the degree to which the eight skills used in Science II classes develop the key competencies of science, and the teaching and assessment methods commonly used in Science II classes. Science teachers generally agreed with the purpose and necessity of introducing student-participatory classes and process-centered assessment, which are the core purpose of the 2015 revised curriculum. However, they had difficulties in practice due to the excessive content of Science II subjects. Problems were also encountered with securing objectivity and fairness during assessments and the operation of online science classes due to COVID-19.

• 국제학술발표논문집
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• The 2th International Conference on Construction Engineering and Project Management
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• pp.711-720
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• 2007

Apartment housing in the Korean domestic construction industry has had various and high-quality finishing work since the enforcement of price deregulation in 1998. Before the enforcement of price deregulation, feasibility studies of housing projects have not had particular difficulties as uniform description of finishing work items were reflected and finishing work cost also was equalized. However, the recent distinction of finishing work based on the same floor plan brings about project cost variation, along with many effects on construction management due to project cost increment. Accordingly, this paper suggests the improved plan of cost management to control the feasibility study result consistently during the life cycle of a project through an analysis based on cost management phase due to cost blackout, appearing at the commencement of a project, cost gradation caused by high-quality finishing work item, and cost reduction due to the degradation of finishing work after analysis of current apartment construction process focused on finishing work using the IDEF process analysis technique.

• 한국산학기술학회논문지
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• 제15권11호
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• pp.6464-6471
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• 2014

웨이퍼 단위의 렌즈를 성형 시 일반적으로 UV경화 방식을 사용한다. 이 경우 발생될 수 있는 문제점은 크게. 경화후 이형과정에서 성형 렌즈의 금형 고착문제, 경화 공정 중 발생하는 소재의 수축 현상으로 렌즈간의 형상 오차 발생 및 웨이퍼 단위의 변형, 위치별 렌즈 형상 편차 발생, 웨이퍼 양면의 렌즈 형상 및 센터 정렬 오차 등이다. 이중 UV경화 과정에 직접적인 영향을 받는 것은 형상 오차 및 변형으로 그 요인은 UV 조사 균일성, UV 강도에 대한 경화도, UV 경화 소재의 수축 특성이다. 따라서 소재에 대한 경화 모델링 수립 및 경화 반응에 따른 수축율과 물성 변화에 대한 이론정립이 필요하다. 또한 이러한 모델링을 해석에 구현할 수 있는 해석 툴 개발이 필요하다. 본 연구에서는 Comsol을 이용하여 수립된 모델링을 반영하고 이를 통하여 웨이퍼 단위 렌즈의 성형 공정에 대한 해석 기법을 제안하였다. 이를 통해 7.2mm에 대한 누적 공차값을 실제 성형 공정 후 결과($0.149{\mu}m$)과 비교하여 제안한 해석 방법에 의한 결과($0.215{\mu}m$)을 비교, 검증을 수행하였으며 이를 통하여 UV경화 공정 후 변형에 대한 해석 가능성을 확인하였다.