• Journal of the Korean Wood Science and Technology
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• v.48 no.3
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• pp.291-302
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• 2020

As the properties of the melamine-urea-formaldehyde (MUF) resins were changing during their storage time, this study investigated the impacts of the synthesis method and melamine content of the MUF resins on the pH, apparent viscosity, molecular weights, and crystallinity to estimate these properties over storage times of up to 30 days. Melaminesat three addition levels (5, 10, and 20 wt% based on the resin solids) were simultaneously reacted with urea and formaldehyde (MUF-A resins), while those at the same addition levels were first reacted with formaldehyde and then with urea(MUF-B resins). The pH values of the MUF-A and MUF-B resins decreased linearly as the storage time increased; the apparent viscosity increased linearly for the low melamine contents (5% and 10%) but increased exponentially for 20%. As anticipated, the molecular weights (Mw and Mn) increased linearly with the storage time, with a steeper increase in the Mw of the MUF-B resins compared with that of the MUF-A resins. The crystallinity of the two resin types decreased with storage time at higher melamine content. The relationships between these properties and the storage time made it possible to estimate the property changes in these resins synthesized by the different synthesis methods and melamine contents; this could help predict the properties of such resins in the industry during their storage.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.27-33
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• 2013

In this paper, we design and analyze the performance of Coordinated Multi-Point (CoMP) techniques to the number of users for next-generation cellular systems. We perform Monte Carlo simulations with Long Term Evolution-Advanced (LTE-Advanced) and confirm the performance from the graph of the Cumulative Distribution Function (CDF). From simulation results, we show the significant performance gain when CoMP technique is used and also show better performance when we apply the various schemes additionally as scheduling and precoding.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1809-1816
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• 2014

This study demonstrates gel-to-fluid transition temperatures of polydiacetylene bilayer vesicles could play important roles in their colorimetric transition temperatures. We prepared five types of polydiaceylene vesicles with 10,12-pentacosadiynoic acid (PCDA) and cholesterol (0-40 mol % of total content). From temperature-dependent observations of the optical signals (colors and UV-vis spectra), the blue-to-red colorimetric transition temperatures of polydiacetylene vesicles were decreased with the cholesterol contents. A further study with microcalorimetry and dynamic light scattering revealed that the polydiacetylene vesicles first underwent gel-to-fluid transitions, which were followed by event(s) responsible for the colorimetric transitions. Energies required for each event were quantified from analysis of the peaks in the microcalorimetry thermograms. The inclusion of cholesterol in the vesicles decreased both the gel-to-fluid and the colorimetric transition temperatures, suggesting that the colorimetric transition of the polydiacetylene vesicles was mediated by the former event although the event was not the direct reason for the color change.

• Geomechanics and Engineering
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• v.12 no.6
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• pp.935-948
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• 2017

An experimental program was conducted to investigate the effects of the static compaction pressure, cement content, water/cement ratio, and curing time on unconfined compressive strength (UCS) of the cement treated sand. UCS were conducted on samples prepared with 4 different cement/sand ratios and were compacted under the lowest and highest static pressures (8 MPa and 40 MPa). Each sample was cured for 7 and 28 days to observe the impact of curing time on UCS of cement treated samples. Results of the study showed the unconfined compressive strength of sand increased as the cement content (5% to 10%) of the cement-sand mixture and compaction pressure (8 MPa to 40 MPa) increased. UCS of sand soil increased 30% to 800% when cement content was increased from 2.5% to 10%. Impact of compaction pressure on UCS decreased with a reduction in cement contents. On the other hand, it was observed that as the water content the cement-sand mixture increased, the unconfined compressive strength showed tendency to decrease regardless of compaction pressure and cement content. When the curing time was extended from 7 days to 28 days, the unconfined compressive strengths of almost all the samples increased approximately by 2 or 3 times.

• Journal of The Korean Society of Integrative Medicine
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• v.1 no.3
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• pp.19-28
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• 2013

Purpose : The purpose of this study was to find out the impact of action-observation training and task-oriented training on activities of daily living performance of stroke patients. Method : 30 stroke patients hospitalized in D hospital located in Busan and treated were randomly allocated to Action-Observation Training Group and Task-Oriented Training Group in fifteens. To compare activities of daily living performance before and after therapy intervention, Korea-modified Barthel index (K-MBI) was carried out. Result : In both groups, activities of daily living performance of stroke patients before and after therapy intervention showed statistically significant differences (p<.05) and activities of daily living performance between two groups after therapy intervention showed statistically significant differences. Conclusion : It was found that action-observation training and task-oriented training improved activities of daily living performance of stroke patients. It is considered that the application of action-observation training and task-oriented training to clinical occupational therapy will show a positive effect on the improvement of activities of daily living performance.

• Journal of the Korean housing association
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• v.26 no.5
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• pp.71-78
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• 2015

Currently, the Korean construction industry is shifting its interest to the overseas construction market because of a stagnating domestic market. In the meantime, the international housing construction market is expanding with respect to new city development projects that are supported by population growth and urban migration. Despite the Korean construction industry's expertise in new city development, technology, and systems for apartment supply, the share of Korean players in the international housing construction market is continuously decreasing. As a measure to overcome this situation, the authors of this study considered the paper "The Development of a Cost Effective, Long-life Housing Model and Construction of Testbed," which is currently in progress as a part of national project. Through literature review and interviews with experts, the authors determined that there are "column+minimum interior (infill)" apartments that are similar to the long-life housing in some areas of China, Southeast Asia, and Russia. Candidate countries expected to be feasible for the entry of long-life housing were selected by determining the top countries that have already entered the long-life housing market and analyzing those selections through additional specific techniques. The external environments of the selected countries were also analyzed. Please refer to the full paper for details.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2013.11a
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• pp.41-42
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• 2013

본 논문에서는 문서 영상 처리의 중요한 전처리 과정인 텍스트 라인 추출을 위하여 가우시안 필터링 및 피크 검출을 이용하는 방법을 제안한다. 이는 문서 영상 내의 글자 영역의 픽셀 강도와 텍스트 라인 사이의 간격에 해당하는 강도의 차이로 인해 문서 영상의 각 열마다 높은 피크와 낮은 피크가 번갈아 가며 나타나는 것에 기반으로, 제안하는 알고리즘은 필터 스케일 추정, 필터량 및 피크 검출, 라인 성분 그룹화의 세 단계로 구성된다. 필터 스케일 추정 단계에서는 여러 초기 값으로 필터링하여 피크 차이 간의 히스토그램을 만듦으로써 글자 크기를 대략적으로 예축하며, 필터링 및 피크 검출 단계에서 앞서 예측된 스케일의 가우시안 필터를 이용하여 필터링 한 후, 각각의 열마다 피크를 검출한다. 마지막으로 라인 성분 그룹화를 통하여 검출된 피크를 서로 연결하여 하나의 텍스트 라인을 구성하는 성분들로 그룹화시켜 텍스트 라인을 추출한다. 실험 결과를 통하여, 제안하는 알고리즘은 이진화 과정을 거치지 않음으로써 균일하지 못한 조명환경 등으로 이진화 성능이 좋지 못할 경우에도 텍스트 라인을 추출할 수 있으며, 텍스트 라인 간격이 인정하지 않고 휘어진 라인을 포함하는 경우에도 적용할 수 있음을 확인 할 수 있다.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5477-5482
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• 2013

Background: Communication plays an important role for the well being of patients, families and also health care professionals in cancer care. Conversely, ineffective communication may cause depression, increased anxiety, hopelessness and decreased of quality life for patients, families and also nurses. Objective: This study aimed to explore communication difficulties of pediatric hematology/oncology nurses with patients and their families, as well as their suggestions about communication difficulties. Materials and Methods: It was conducted in a pediatric hematology/oncology hospital in Ankara, Turkey. Qualitative data were collected by focus groups, with 21 pediatric hematology/oncology nursing staff from three groups. Content analysis was used for data analysis. Results: Findings were grouped in three main categories. The first category concerned communication difficulties, assessing problems in responding to questions, ineffective communication and conflicts with the patient's families. The second was about the effects of communication difficulties on nurses and the last main category involved suggestions for empowering nurses with communication difficulties, the theme being related to institutional issues. Conclusions: Nurses experience communication difficulties with children and their families during long hospital stays. Communication difficulties particularly increase during crisis periods, like at the time of first diagnosis, relapse, the terminal stage or on days with special meaning such as holidays. The results obtained indicate that pediatric nurses and the child/family need to be supported, especially during crisis periods. Feeling of empowerment in communication will improve the quality of care by reducing the feelings of exhaustion and incompetence in nurses.

• Journal of Korean Library and Information Science Society
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• v.46 no.2
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• pp.113-129
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• 2015

The aim of this study is to analyse the relationships between the usefulness of information literacy education and life satisfaction on the older adults in Korea. How the information literacy education impact on the information activities is an additional research question. To achieve these objectives, data were collected through the 227 respondents of over 50-years-old adults in Korea and analysed using AMOS for the structural equation modeling. In this study, information literacy education was measured by it's usefulness aspects, and information activities were measured by it's convenience aspects. The results showed that the information literacy education influences positively both in life satisfaction and in information activities.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.167.2-167.2
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• 2014

In this work, ZnO shell on mesoporous $SiO_2$ ($ZnO/SiO_2$) was prepared by atomic layer deposition (ALD). Diethylzinc (DEZ) and $H_2O$ were used as precursor of ZnO shell. $ZnO/SiO_2$ sample was characterized by X-ray diffraction (XRD), N2 sorption isotherms, X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR). $ZnO/SiO_2$ showed higher adsorption capacity of MB than that of bare mesoporous $SiO_2$ and the adsorption capacities of $ZnO/SiO_2$ could be regenerated by UV exposure through the photocatalytic degradation of the adsorbed MB. This system could be used for removing organic dye from water by adsorption and reused after saturation of adsorption due to its photocatalytic regeneration.