• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.24-24
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• 2018

Degraded plantation forests are increasing because of unfavorable forestry conditions prevailing in Japan, including falling timber prices, increasing operational costs, and aging and declining forestry workforce. To remedy this situation, appropriate management strategy is required. This study introduces the challenges of Odai Town, Mie Prefecture that employed a new management strategy by evaluating site suitability for conifer forests and that proposes a new forest management regime of planting deciduous trees in unsuitable sites. The site suitability for conifer forests was evaluated from two aspects: the natural site conditions and the relationship among site conditions, growth, and damage by Anaglyptus subfasciatus Pic. in Cryptomeria japonica D. Don and Chamaecyparis obtusa Sieb. Et Zucc. forests. By analyzing the relationship among site conditions, growth, and insect damage based on field data obtained in plantation forests, growth evaluation and insect damage evaluation maps were developed. Based on the natural forest investigation, natural site condition maps for C. japonica and C. obtusa were established. Furthermore, by integrating these evaluation maps with the forest road maps showing the accessibility to the forest, the forest management regime for the whole plantation area of Odai Town was established. The forest management regime map indicates the sites suitable for forestry: suitable for long-rotation, short-rotation, and potential sites for short-rotation. The sites unsuitable for forestry were considered to be more suitable for broadleaved forests. Clear-cutting was conducted in a small area and different seral stage saplings (approximately 20 deciduous tree species) suitable to the site conditions were planted in an area of $80-120m^2$ protected by deer-fences. This might establish a forest composed of many species with a multilayer vertical forest structure in a short period. The planted saplings were distributed neither randomly nor uniformly to reflect the natural distribution of trees in the forest. A challenge to develop new products using the deciduous trees has started, such as wood chips for preparing smoked food, essential oil, and deodorizer. As these challenges have just begun, their effects on enhancing sustainable resource management are still being monitored. Even with the challenges, this regime can be of high value as a management strategy to remedy the situation of expansion of degraded forests in Japan.

• 정보화정책
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• 제29권3호
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• pp.82-104
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• 2022

일반 사용자들이 특정 주제에 관한 짧은 바이럴 동영상을 모방·제작·공유하는 해시태그 챌린지는 숏폼 비디오 플랫폼의 흥미로운 사회 현상 중 하나로 단연 손꼽힌다. 그러나 해시태그 챌린지의 인기가 높아지고 있음에도 불구하고, 관련 사용자 행동에 대한 이론적 논의는 여전히 매우 부족하다. 본 연구는 해시태그 챌린지에 대한 사용자의 참여 의도를 보다 정확히 이해하기 위해서 마이크로 인플루언서의 영향을 관심있게 살펴보고자 하였다. 이를 위해 준사회적 상호작용 이론과 모방 행동 문헌을 주요 이론적 근거로 활용하였다. TikTok 사용자를 대상으로 한 243개 설문조사 데이터를 분석한 결과, 본 연구는 사용자가 마이크로 인플루언서와 친밀감을 느끼는 환상(즉, 준사회적 상호작용)이 해시태그 챌린지에 대한 유저의 참여 의도에 상당한 긍정적인 영향을 미친다는 것을 알 수 있었다. 또한, 숏폼 비디오 플랫폼에서 준사회적 상호작용의 정도는 크게 미디어 콘텐츠 관련 요소와 미디어 캐릭터 관련 요소(콘텐츠 매력도, 신체적 매력도, 태도 유사성)에 의해 결정된다는 것을 알 수 있었다. 본 연구는 숏폼 비디오 플랫폼에서 마이크로 인플루언서의 활용 효과를 높이기 위한 방법에 관한 이론적·실무적 시사점을 제공한다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2007년도 춘계 학술대회논문집
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• pp.120-124
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• 2007

Helicopters and rotary-wing vehicles encounter a wide variety of complex aerodynamic phenomena and these phenomena present substantial challenges for computational fluid dynamics(CFD) models. This investigation presents the rotor aerodynamic analysis items for the helicopter development and variety aerodynamic analysis methods to provide the better solution to researchers and helicopter developers between aerodynamic problems and numerical aerodynamic analysis methods. The numerical methods to make an analysis of helicopter rotor are as below - CFD Modelling : actuator disk model, BET model, fully rotor model,... - Grid : sliding mesh, chimera mesh / structure mesh, unstructure mesh,... - etc. : panel method periodic boundary, quasi-steady simulation, incompressible,... The choice of CFD methodology and the numerical resolution for the overall problem have been driven mostly by available computer speed and memory at any point in time. The combination of the knowledge of aerodynamic analysis items, available computing power and choice of CFD methods now allows the solution of a number of important rotorcraft aerodynamics design problems.

• 휴양 및 경관연구
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• 제12권4호
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• pp.17-24
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• 2018

With industrialization, environmental problems have become severe worldwide as resources are exhausted for mass production purposes and pollutants are produced in excess of nature's capacity to absorb them. Since modernity, urban parks have emerged as an important element for addressing challenges facing urban environments, which include environmental degradation. In 1987, the Brundtland Commission's report presented a sustainable developmental perspective in solving environmental problems and provided ideas for sustainable design and sustainable urban park landscape design. The purpose of this study is to analyze sustainable design applied to Houtan Park in central Shanghai, China from the perspective of social culture preservation, ecological restoration, and economic effect, and to provide the basic data for urban park design in similar areas in the future. This study consists of a literature survey and a field investigation. The field investigation lead to analysis from three perspectives: social culture preservation, ecological restoration, and economic effect. The literature survey examined sustainable urban parks and Houtan Park based on relevant papers, newspaper articles, and reports. Through actual visits (Aug. 28 - Sep. 1, 2018), it also examined the elements of sustainable design that were applied to the architecture. The three sustainable design elements derived from this study, being a sustainable design for the future, will be used as an important basis for developing urban parks for the regeneration of brownfields in many areas in China.

• Advances in nano research
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• 제15권2호
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• pp.113-128
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• 2023

The advancement of theoretical research has numerous challenges, particularly with regard to the modeling of structures, in contrast to experimental investigation of the mechanical behavior of complex systems. The main objective of this investigation is to provide an analytical analysis of the static problem of a new generation of composite structure, namely, functionally graded FG graphene reinforced composite GRC coated plates/shells. A complex power law function is used to define the material's graduation. Investigations are conducted on Hardcore and Softcore coated FG plates/shells. The virtual work approach is used to perform the equilibrium equations, which are then solved using the Galerkin technique to account for various boundary conditions. With reliable published articles, the presented solution is validated. The effects of hardcore and softcore distributions, gradation indexes, and boundary conditions on the buckling, bending deflection and stresses of FG GRC-coated shells are presented in detail. Obtained results and the developed procedure are supportive for design and manufacturing of FG-GRC coated plates/shells in several fields and industries e.g., aerospace, automotive, marine, and biomedical implants.

• Journal of Advanced Marine Engineering and Technology
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• 제37권3호
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• pp.274-281
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• 2013

The variable demand on the energy market requires a great flexibility in operating hydro turbines. However, Francis turbine operated at off-design conditions poses technical challenges related to large unsteady forces given by residual swirl and angular momentum. In order to improve the performance of a Francis turbine, the paper presents a numerical investigation of the 3D flow in the turbine at off-design conditions and discusses the influence of variable guide vane openings on the internal flow of a Francis turbine with the help of computational fluid dynamics. First, the internal flow characteristics of Francis turbine operated by varied guide vane angle at off design condition are computed and the optimal guide vane angle is obtained. Secondly, the Francis turbine is operated with guide vane number varies at the optimal guide vane angle. Finally, pressure contours and velocity distributions in the distributor are discussed and compared.

• 대한공업교육학회지
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• 제30권1호
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• pp.1-18
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• 2005

The purpose of this study was to development a model of problem solving instruction for improving practical skill-competence in technical high school. For the study, various literature researches were reviewed intensively about problem solving process, laboratory instruction's approaches and learning principals. The problem solving instruction process was composed with identifying problems, generating alternative solutions, investigation and research, choosing a solution, acting on a plan, modeling of problem solving, testing and evaluating, redesigning and improving. The skills schema combines a four domain of skilled activity, that is, cognitive skills, psychomotor skills, reactive skills and interactive skills. The problem solving instruction was composed with five major learning systems-emotional, social, cognitive, physical, and reflective-that can be used extensively as generic lesson plashing. The teacher serves as a coach or guide for student learning. As a facilitator, the teacher challenges, questions, and stimulates the students in their thinking, problem solving and self-directed study. In this process, students represent problem with think aloud, assume responsibility for their learning and move from teacher-centered to student-centered education.

• Journal of Computing Science and Engineering
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• 제2권3호
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• pp.221-248
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• 2008

Data provenance is the background knowledge that enables a piece of data to be interpreted and used correctly within context. The importance of tracking provenance is widely recognized, as witnessed by significant research in various areas including e-science, homeland security, and data warehousing and business intelligence. In order to further advance the research on data provenance, however, one must first understand the research that has been conducted to date and identify specific topics that merit further investigation. In this work, we develop a framework based on semiotics theory to assist in analyzing and comparing existing provenance research at the conceptual level. We provide a detailed review of data provenance research and compare and contrast the research based on d semiotics framework. We conclude with an identification of challenges that will drive future research in this field.

• The Journal of Asian Finance, Economics and Business
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• 제1권2호
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• pp.5-13
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• 2014

The purpose of this paper is to carry out an empirical analysis of the link that exists between microfinance and poverty alleviation. The analysis is driven by literature searches on empirical works done by different researchers in different contexts. Qualitative research methodology was adopted, following a desktop approach. An empirical literature review took a centre stage in this investigation. An analysis of empirical works shows that microfinance enhances poverty alleviation despite the challenges such as the Indian Andhra Pradesh crisis. The paper is limited to a review of empirical sources of literature. A field survey, supported by an econometric analysis would have helped to generate robust results. This paper attempts to bring together the empirical works that were done in different contexts to shed light on the important relationship between microfinance and poverty. Many research works on microfinance depend upon personal anecdotes, thus this present paper attempts to compile the scattered empirical findings on microfinance and poverty alleviation.

• 한국과학교육학회지
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• 제32권8호
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• pp.1367-1377
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• 2012

Inquiry activity is a major source of student investigation which both of the national curriculum standards strongly emphasize for achieving scientific literacy. The purpose of this study was to examine inquiry activities incorporated in high school biology textbooks used in China and Korea. The inquiry activities were examined with regard to inquiry level and science process skills. Bell's and a modification of Padilla's framework were used in these analyses. Results show that the Korean textbooks were more exclusively occupied by simple inquiry activities - None of them provided activity more complex than level 2 inquiry. In addition, the Korean textbooks had uniformly basic science process skills, whereas their Chinese counterparts gave students some challenges for higher level process skills. Therefore, it cannot be guaranteed that the activities in the Korean textbooks are helpful in guiding students toward a gradual progression to high-level inquiry. Implications for inquiry-based science education were suggested based on the results of the study.