• Wind and Structures
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• 제29권2호
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• pp.87-98
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• 2019

As a regenerated turbulent wind field process, wind tunnel test has proven to be a promising approach for investigating the transmission tower-line system (TTLS) performance in view of experimental scaled models design, simulation techniques of wind field, and wind induced responses subjected to typhoon. However, the challenges still remain in using various wind tunnels to regenerate turbulent wind field with considerable progress having been made in recent years. This review paper provides an overview of the state-of-the-art of the wind tunnel based on active or passive controlled simulation techniques. Specific attention and critical assessment have been given to: (a) the design of experimental scaled models, (b) the simulation techniques of wind field, and (c) the responses of TTLS subjected to typhoon in wind tunnel. This review concludes with the research challenges and recommendations for future research direction.

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2019년도 하계 학술발표초록집
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• pp.289-289
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• 2019

• 한국응용과학기술학회지
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• 제31권2호
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• pp.329-336
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• 2014

The conductive polymer composites have attracted considerable attention in the field of industry due to their electrical properties. To understand electrical properties of the composites, their volume specific resistance was measured. Electrical conductivity results showed percolation phenomena. Percolation theories are frequently applied to describe the insulator-to-conductor transitions in the composites composed of conductive filler and insulating matrix. It was found that the percolation threshold strongly depends on the aspect ratio of filler particles. The critical concentration of percolation formed is defined as the percolation threshold. The purpose of this study was to examine electrical properties of the epoxy resins filled with nickel. The sample was prepared using vehicle such as epoxy resin replenished with nickel powder, and the evaluation on their practical use was performed in order to apply them to electric and electronic industry as well as general field. The volume specific resistance of epoxy resin composites was 4.666~13.074 when using nickel powder. Weight loss of the conductive composites took place at $350^{\circ}C{\sim}470^{\circ}C$.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.894-896
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• 2003

Koh Chang Island is located near the east border of Thailand. The government of Thailand promotes the island as a model of eco-tourism spots. The Island undeveloped until recent years, is expected to change to major tourist attraction. 'Digital Koh Chang project' has thus. The main objective of this project is to monitor the environment and land use status of the island and to support its sound development. In March 2003, a field survey of this project was planned and field data were collected using both airborne and ground platforms and an ocean vessel. These data were combined with satellite data in the laboratory. This presentation is all balloon-born system field operation. A 5-meter length balloon filled with Helium gas was used, whose payload consisted of two RGB standard color digital still cameras, two directional rotating servo motors, a camera mount cradle as well as signal transmitting and receiving components. A series of aerial high-resolution digital images were rather easily obtained using this inexpensive system, making it possible to monitor intended landscape features in a specific field. Design of simple, low-cost and easily transportable flying platforms and local field surveys using them are useful for getting local ground truth data to calibrate satellite or airborne-based RS data. The design analysis to upgrade the system is further investigated.

• 대한수의학회지
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• 제45권2호
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• pp.199-205
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• 2005

DNA fingerprint patterns of 8 Brucella reference strains and 15 B. abortus field isolates were characterized by repetitive element sequence-based PCR (rep-PCR) using BOX- and ERIC-primers in this study. AMOS PCR differentiated all Brucella field isolates from B. abortus RB51, a vaccine strain by producing a B. abortus-specific 498 bp band. Rep-PCR using BOX-primer produced 13 to 18 bands with sizes of between 230 and 3,300 bp, and discriminated Brucella strains to the species level except B. canis and B. suis. PCR products amplified with ERIC primers were, however, not appropriate for differentiating the Brucella isolates. DNA fingerprint patterns for all B. abortus field isolates were identical among them and were put on one cluster with B. abortus biovar 1 reference strain in the dendrogram, indicating they were highly clonal. These results suggested that rep-PCR using BOX primer might to be a useful tool for calculating genetic relatedness among the Brucella species and for the study of brucellosis epidemiology.

• 문화기술의 융합
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• 제10권4호
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• pp.227-234
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• 2024

본 연구는 도서관 현장실습이 학생들의 실무기술 향상에 효과가 있었는지 분석하고, 이를 통해 현장실습 프로그램이 적절하게 설계 및 운영되었는지를 확인하여 향후 개선방안을 도출하는 것에 그 목적이 있다. 이를 위해 문헌정보학의 6개 전공영역과 30개의 세부실무기술을 도출하고, D대학교 문헌정보학과 4학년 학생 19명을 대상으로 현장실습전후 설문조사를 진행하였다. 연구결과, 세부 실무기술 중 9개에 대한 중요도와 15개에 대한 인식의 변화가 있었으며, 실제 현장실습에서 다뤄진 실무기술에 대한 항목은 긍정적으로 변화한 것을 확인할 수 있었다. 그러나 현장에서 다뤄지지 않은 실무기술에 대해서는 수준 향상 뿐 아니라 중요성 대한 인식조차 기존의 생각이 유지되거나 부정적으로 변화하였다. 이에 향후 학생들이 실습에서 함양해야 할 기술이 무엇인지 세부항목별로 제안하고, 현장에서 이를 반영할 수 있도록 구체적인 실습가이드라인을 제시하는 등 적극적이고 지속적인 노력이 수반되어야 할 것으로 보인다.

• 한국환경교육학회지:환경교육
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• 제21권3호
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• pp.1-12
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• 2008

This study is aimed at suggesting ways to develop field trip or learning materials focusing on environment of Jeju seashore in order to make an effective field trip. To perform these purposes, the contents and concepts were analyzed from environment-related 'geological unit' of elementary science textbook. Afterwards, the places having the geological features in coincidence with them are chosen, and investigated, and these regions can develop into geological teaming places for field trip. Each teaming spot focuses on understanding and finding out the characteristic geological environment of rock shore, gravel shore, sand shore, shellfish shore, and tideland shore among Jeju shores. When field trip is conducted at the preparatory stage, students can get advance knowledge on geological concepts from textbook. The activity record paper is presented at the field trip stage where students observe geological phenomena on their own. After field trip is finished, the summary stage is given to solve some problems on the basis of the observed contents. The developed data from this research have its regional limits, but is surely useful for teachers who try to plan field trip when they especially choose the right field trip spots, or plan to make the process for field trip preparation of the environmental education. Furthermore, with this survey and activities, students can take the chance to improve the learning effect through their own experience on environment of Jeju seashore.

• 4차산업연구
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• 제3권2호
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• pp.11-17
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• 2023

Purpose - Recently, in the field of language education, interest in edutech has increased due to difficulties in classroom teaching due to COVID-19. Accordingly, we would like to analyze research topics related to e-learning before and after COVID-19 and examine the implications for the future Korean language education field. Research design, data, and methodology - This study organized a list of papers to be analyzed by searching for e-learning terms applicable to Korean language education in RISS. The collected data was electronically documented, keywords were extracted using text mining techniques, and word frequencies were checked, and then viewed through cloud visualization. Result - It was confirmed that research on e-learning in the field of Korean language education has increased rapidly in 2021 and 2022. In particular, extensive research on online learning methods has been actively conducted due to the difficulties of face-to-face learning in the COVID-19 era. There have been many studies on teaching and learning methods, such as flipped learning, hybrid learning, blended learning, mobile learning, and smart learning. Conclusion - Since the research so far has mainly focused on online class management methods. Therefore, future research suggests that efforts should be made to develop educational contents and teaching methods using specific ICT technologies. These efforts will contribute to advancing smart education that future education aims for.

• ETRI Journal
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• 제39권4호
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• pp.570-581
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• 2017

Multiplication in finite fields is used in many applications, especially in cryptography. It is a basic and the most computationally intensive operation from among all such operations. Several systolic multipliers are proposed in the literature that offer low hardware complexity or high speed. In this paper, a bit-parallel polynomial basis systolic multiplier for generic irreducible polynomials is proposed based on a modified interleaved multiplication method. The hardware complexity and delay of the proposed multiplier are estimated, and a comparison with the corresponding multipliers available in the literature is presented. Of the corresponding multipliers, the proposed multiplier achieves a reduction in the hardware complexity of up to 20% when compared to the best multiplier for m = 163. The synthesis results of application-specific integrated circuit and field-programmable gate array implementations of the proposed multiplier are also presented. From the synthesis results, it is inferred that the proposed multiplier achieves low power consumption and low area complexitywhen compared to the best of the corresponding multipliers.

• 한국건설관리학회논문집
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• 제11권1호
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• pp.48-58
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• 2010

건설사업관리(Construction Management, CM)제도의 적용확대와 함께 관련 학계 및 연구계에서도 CM의 세부분야별로 활발한 연구들을 진행하고 있으며, 다양한 연구 성과물들이 양산되고 있다. 지속적인 CM연구의 활성화를 위해서는 최근 국내외 연구 주제들의 동향을 파악하는 것이 중요하며, 이로써 국내외의 취약 연구 분야와 관련 기술을 유추할 수 있다. 본 연구는 CM의 주요 기술 분야별 주제분류 코드체계를 구성하여 각 주제별로 최근 5년간 2,000여편의 국내외 관련 논문을 대상으로 세부 분야별 연구동향을 분석하고 있다. 분석결과 국내외 CM연구 분야별 강점 및 취약분야와 최근의 연도별 연구동향 추이를 파악할 수 있었으며, 이를 바탕으로 CM분야의 연구 활성화를 위한 추진방향을 제시하고 있다.