• 센서학회지
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• 제21권4호
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• pp.263-269
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• 2012

Al doped ZnO(AZO) thin films were deposited at different substrate temperatures by a continuous composition spread(CCS) method. Various compositions of Al doped ZnO thin films deposited at substrate temperatures between 0 and $250^{\circ}C$ were explored to find excellent electrical and optical properties. The AZO thin film deposited at $100^{\circ}C$ had the lowest resistivity, $9{\times}10^{-4}{\Omega}$ cm and its average transmittance at the 400 to 700 nm wavelength region was 92 %. Optimized composition of the AZO thin film which had the lowest resistivity and high transmittance was 3.13 wt% Al doped ZnO.

• 한국연소학회지
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• 제3권2호
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• pp.1-11
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• 1998

Experimental investigation on flame spread of blended fuel droplet arrays has been conducted for droplet diameters of 1.0mm and 0.75mm using high-speed chemiluminescence images of OH radical. The flame spread rate is measured with blended fuel composition, droplet diameter, and droplet spacing. Flame spread is categorized into two: a continuous mode and an intermittent one. There exist a limit droplet spacing, above which flame does not spread, and a droplet spacing of maximum flame spread, which is closely related to flame diameter. It is seen that flame spread rate is mainly dependent upon the relative position of flame zone within a droplet spacing. In case of large droplet, the increase of % volume of Heptane induces the shift of limit droplet spacing to a larger spacing since volatile Heptane plays a role of an enhancer of flame spread rate. In case of small droplet, the increase of % volume of Heptane leads to the shift of limit droplet spacing to a smaller droplet spacing. This is so because of the delayed chemical reaction time by the rapid increase of mass flux of fuel vapor for small droplet.

• 마이크로전자및패키징학회지
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• 제17권2호
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• pp.35-40
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• 2010

CCS방법이 적용된 off-axis RF 마그네트론 스퍼터를 이용하여 증착된 $Ta_2O_5-SiO_2$의 유전체 박막에 관하여 연구를 하였다. 1500 ${\mu}m$ 의 간격으로 비유전율 및 유전손실을 측정하여 $Ta_2O_5-SiO_2$에 조성의 변화에 따른 유전특성의 변화를 나타내었다. 1MHz 에서 높은 유전상수(k~19.5) 와 낮은 유전손실(tan${\delta}$<0.05)을 보이는 영역들을 찾았는데, 이는 증착된 기판($75{\times}25mm^2$ sized Pt/Ti/$SiO_2$(100))에서 $SiO_2$/Si 타겟 영역으로부터 각각 16 mm, 22 mm 떨어진 영역에서 찾을 수 있었다.

• 무역상무연구
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• 제43권
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• pp.481-507
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• 2009

Along with continuous increase in international investments encouraged by wide spread bilateral investment treaties (BIT) including free trade agreements (FTA), international investment disputes have been also increasing. This means that a host State, an importer of foreign investments, and a investor who exports its investment to foreign State, need to take measures to prevent international disputes arising from international investment or to prepare for the arbitration for resolving the disputes. Under these circumstances, this paper compares ICSID arbitration rules and UNCITRAL arbitration rules in respect of (i) the institution of arbitration, (ii) the appointment of arbitrators and the composition of arbitral tribunal, and (iii) the procedures for, and the form of, arbitral awards. On base of this comparison, this paper further suggests certain practical issues that the host State's government and the foreign investors should be aware of in order to be ready for the resolutions of disputes by ICSID or UNCITRAL arbitrations.

• 농촌계획
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• 제26권4호
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• pp.27-39
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• 2020

With the COVID-19 pandemic, the global economy has stagnated and our daily lives have changed. The rural economy is also experiencing damage, such as an average of 65% or more decrease in the number of visitors to rural experience resort villages due to the spread of COVID-19. In order to minimize the damage arising from the prolonged coronavirus, a hospitality system in response to changes in rural tourism behavior and consumer demand is needed to revitalize rural areas and maintain continuous economic independence. Therefore, this study attempted to find ways to utilize landscape resources such as education, culture, history, and ecology in order to complement the existing experience programs in connection with local resources and local environment. Wibong Village, which is the subject of the study, attempted to revitalize the village using the resources through the "Creative village creation" project in 2015. Due to poor management of historical resources, difficulty in operating experience programs, and response to changes in the natural environment, the rate of implementation of the project plan was very low. Currently, the demand for experience is also decreasing due to the COVID-19 effect, so it was judged that it was necessary to develop an experience village program suitable for the needs of experienced visitors by discovering additional local resources for the continuous operation of the experience village. In order to solve the problem of the use of landscape resources and the spatial composition of the study site, additional investigations of local resources were made, and an experience program course that could be operated by theme was proposed by configuring a space suitable for the use of landscape resources. By dividing the additionally investigated landscape resources into history, ecology, and region, an experiential course was created to separate the traffic lines, and the space composition for large-scale experienced visitors that had been previously operated was constructed in a form suitable for the post-corona era. In addition, at least two experiential tour courses that can be operated by period were proposed to maintain economic effects. Starting with this study, if further research on the creation and spatial composition of a rural experience village centered on the connection with the region, it will be used as research results that can be referenced in projects such as village creation, rural space planning, and living area analysis. It is expected that it will be able to effectively cope with the construction of a rural area suitable for the post-corona era, where demand is expected to increase in the future.

• 한국실내디자인학회논문집
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• 제19권2호
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• pp.90-98
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• 2010

The concepts of laws like regularity or persistence or recurrence those are discovered in nature, became the essential elements in speculative philosophy, study and scientific technology. Western civilization was spread out by these natural laws. As this background, this study is aimed to research the theories of natural laws and the development of geometry as the descriptive tools and the development aspects of the concepts of space. According to Whitehead's four theories on the natural laws, the result of this study that aimed like that as follows. First, the theories on the immanence and imposition of the natural laws were the predominant ideas from ancient Greek to before the scientific revolution, the theory on the simple description like the positivism made the Newton-Cartesian mechanism and an absolutist world view. The theory on the conventional interpretation made the organicism and relativism world view according to non-Euclidean geometry. Second, the geometrical composition of ancient Greek architecture was an aesthetics that represented the immanence of natural laws. Third, in the basic symbol of medieval times, the numeral symbol was the frame of thought and was an important principal of architecture. Fourth, during the Renaissance, architecture was regarded as mathematics that made the order of universe to visible things and the geometry was regarded as an important architectural principal. Fifth, according to the non-Euclidean geometry, it was possible to present the natural phenomena and the universe. Sixth, topology made to lapse the division of traditional floor, wall and ceiling in contemporary architecture and made to build the continuous space. Seventy, the new nature was explained by fractal concepts not by Euclidean shapes, fractal presented that the essence of nature had not mechanical and linear characteristic but organic and non-linear characteristic.

• 한국정보통신학회논문지
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• 제18권6호
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• pp.1381-1387
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• 2014

지속적인 정보기술의 발전으로 최근 인문학, 지역학 등 다른 학문 분야와의 융합에 대한 필요성이 대두되고 있다. 정보기술과 인문 지역학의 융합 분야 중에서 전자문화지도는 점, 선, 면의 공간데이타와 시간, 공간, 주제를 통하여 다양한 문화정보를 디지털화하여 전자지도 위에 표현한다. 지식지도는 전자문화지도의 활용을 고도화시킨 개념으로, 기존의 전자문화지도 상에 전문학술정보를 표현하는 것이다. 이 지식지도는 세부적으로 전자문화지도와 연계하여 학술정보를 제공하므로 주제별, 지역별, 시대별 데이터가 유기적으로 연결된 시각적이고 통합적인 정보 공유 및 확산이 가능하다. 따라서 지식지도 구축이 활성화되면 효율적인 학문 연구 및 연구결과 확산을 위한 도구로 활용될 수 있다. 본 논문에서는 먼저 지식지도에 대한 전반적인 개념, 구성에 대한 연구 내용을 기술하고, 이를 기반으로 실제 지식지도 구현을 위한 설계를 제시한다.

• 한국초등과학교육학회지:초등과학교육
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• 제38권3호
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• pp.317-330
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• 2019

The purpose of this study is to investigate the influences of science leading schools on primary and middle school students' positive experiences about science (PES) through in-depth interviews with teachers in charge of science leading schools. Science leading schools at the primary and middle school level such as Creative Convergent Science Labs and Student Participatory Science Classes were investigated and 11 teachers were participated in focus group interviews. Teacher in-depth interviews were conducted to explore the factors that led to the effectiveness of science leading schools in improving the student's PES in light of operational characteristics of science leading schools, characteristic factors of science leading schools on students PES, and improvement plans and requirements of science leading schools, as well as implications for general high schools. Science leading schools including Creative Convergent Science Labs and Student Participatory Science Classes applied for the leading school funding to secure supplies, equipments, and lab improvement for authentic science classes. In addition, reconstructed the curriculum more broadly than before, and emphasized and expanded student participatory classes and process-centered assessment at the teacher learning community level. Through student-participatory classes, the science leading schools stimulate students' interest in science, provide students with PES) through various instructions including projects, engage students in interesting science experiences in Creative Convergent Science Labs, and enhance inquiry skills and PES as well as science content knowledge. Based on the results, ways to spread the characteristics of science leading schools to general schools are suggested including expanding budget support, securing the space of science labs and improving spatial composition, providing diverse teaching and learning materials, diversifying assessment subjects and methods, and the necessity of teachers' continuous professional development, etc.

• Ecology and Resilient Infrastructure
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• 제6권4호
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• pp.191-199
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• 2019

도로 공사는 자연 생태계를 훼손하고, 떨어진 경관들을 긴 통로구조로 연결함으로써 외래식물의 침입 및 확산에 중요한 요인으로 고려된다. 본 연구는 도로 공사가 외래식물 조성 변화에 미치는 영향을 파악하기 위하여, 공사가 진행 중인 사업장에서 절토사면, 성토사면 및 평탄지의 지형특성에 따라 외래식물상 조사를 수행하였다. 지속적인 교란이 발생하는 사업으로써 일·이년생 외래식물에서 주로 증감이 발생하였다. 지형특성별 외래식물상 변화는 절토사면에서 감소하는 반면, 성토사면에서 증가하는 것으로 나타났으며, 평탄지는 발생장소에 따라 증감 특성이 달랐다. 이러한 외래식물상 변화의 원인은 비의도적으로 유입된 외래식물에 의해 주도되었다. 특히 성토사면에서 비의도적으로 유입되는 외래식물이 증가하는 것으로 연구되어, 성토사면이 생태계교란식물과 같은 위해성 높은 외래식물의 공급원으로 이용되지 않도록 관리하여야 한다. 반면 의도적으로 도입된 식재종들은 파종 시부터 대량 살포하기 때문에 군집을 형성하기 쉬우며 비식재지인 평탄지까지 확산하는 것을 파악할 수 있었다. 따라서, 도로공사 중이나 공사 후 도로사면 식생이 주변 생태계에 미치는 영향을 최소화되도록, 성토사면 조경계획에 지속성이 높은 고유종 식재를 환경영향평가 협의 시에 제안하는 것이 바람직하다.

• 대한치과보철학회지
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• 제43권3호
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• pp.363-378
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• 2005

Statement of problem. Hydroxyapatite(HA) coated titanium surfaces have not yet showed the reliable osseointegration in various conditions. Purpose. This study was aimed to investigate microstructures, chemical composition, and surface roughness of the surface coated by the hydrothermal method and to evaluate the effect of hydrothermal coating on the cell attachment, as well as cell proliferation. Material and Methods. Commercially pure(c.p.) titanium discs were used as substrates. The HA coating on c.p. titanium discs by hydrothermal method was performed in 0.12M HCl solution mixed with HA(group I) and 0.1M NaOH solution mixed with HA(group II). GroupⅠ was heated at 180 $^{\circ}C$ for 24, 48, and 72 hours. GroupⅡ was heated at 180 $^{\circ}C$ for 12, 24, and 36 hours. And the treated surfaces were evaluated by Scanning electron microscopy(SEM), Energy dispersive X-ray spectroscopy(EDS), X-ray photoelectron spectroscopy(XPS), X-ray diffraction method(XRD), Confocal laser scanning microscopy(CLSM). And SEM of fibroblast and 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) assay were used for cellular responses of the treated surfaces. Results. The color of surface changed in both groups after the hydrothermal process. SEM images showed that coating pattern was homogeneous in group II, while inhomogeneous in group I. H72 had rosette-like precipitates. The crystalline structure grew gradually in group II, according to extending treatment period. The long needle-like crystals were prominent in N36. Calcium(Ca) and phosphorus(P) were not detected in H24 and H48 in EDS. In all specimens of group II and H72, Ca was found. Ca and P were identified in all treated groups through the analysis of XPS, but they were amorphous. Surface roughness did not increase in both groups after hydrothermal treatment. The values of surface roughness were not significantly different between groups I and II. According to the SEM images of fibroblasts, cell attachments were oriented and spread well in both treated groups, while they were not in the control group. However, no substantial amount of difference was found between groups I and II. Conclusions. In this study during the hydrothermal process procedure, coating characteristics, including the HA precipitates, crystal growth, and crystalline phases, were more satisfactory in NaOH treated group than in HCl treated group. Still, the biological responses of the modified surface by this method were not fully understood for the two tested groups did not differ significantly. Therefore, more continuous research on the relationship between the surface features and cellular responses seems to be in need.