• 신재생에너지
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• 제16권1호
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• pp.15-24
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• 2020

For mechanical load testing of wind turbines, capture matrix is constructed for various range of wind speeds according to the international standard IEC 61400-13. The conventional method wastes considerable amount of data by its invalid data policy -segment data into 10 minutes then remove invalid ones. Previously, we have suggested an alternative way to save the total amount of data to build a capture matrix, but the efficient selection of data has been still under question. The paper introduces optimization algorithms to construct capture matrix with less data. Heuristic algorithm (simple stacking and lowest frequency first), population method (particle swarm optimization) and Q-Learning accompanied with epsilon-greedy exploration are compared. All algorithms show better performance than the conventional way, where the distribution of enhancement was quite diverse. Among the algorithms, the best performance was achieved by heuristic method (lowest frequency first), and similarly by particle swarm optimization: Approximately 28% of data reduction in average and more than 40% in maximum. On the other hand, unexpectedly, the worst performance was achieved by Q-Learning, which was a promising candidate at the beginning. This study is helpful for not only wind turbine evaluation particularly the viewpoint of cost, but also understanding nature of wind speed data.

• 한국도서관정보학회지
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• 제34권4호
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• pp.43-66
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• 2003

오늘날 많은 학술도서관이 장서개발에 접근패러다임을 적극적으로 대입하고 있다. 그 대표적인 사례가 전자잡지의 수용이며, 그것의 가장 큰 이점은 최신의 연구논문이 인터넷에 산재하는 플랫폼을 통하여 데스크탑으로 전달된다는 점이다. 그럼에도 불구하고 아직은 전자잡지가 구독(라이센스)가격, 인쇄잡지의 지속적인 생존력, 아카이빙, 접근 및 이용이 편의성 등의 난제로 인하여 학술커뮤니케이션의 주류매체로 공인 받지 못하고 있을 뿐만 아니라 많은 곡해마저 양산하고 있다. 이에 본 연구는 학술지의 구매력 저하, 선택(평가)기준의 부재, 영향계수의 가외성과 남용, 디지털 접근패러다임과 후광효과, 전자잡지 수급의 부 정합, 주제 게이트웨이 기능의 부실 등의 측면에서 디지털 아킬레스건의 개연성을 분석하고자 한다.

• 한국통신학회논문지
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• 제38C권8호
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• pp.651-662
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• 2013

본 연구에서는 적용대상체계에 적합한 시큐어 코딩룰을 선정 평가하기 위한 방안으로, 적용대상 체계의 특성에 따른 체계적용적합성(개발언어적합성, 플랫폼적합성), 위협평가(침해의 심각성, 침해의 가능성), 적용기대효과(신뢰성/품질향상, 수정 비용) 등을 종합적으로 고려한 시큐어 코딩룰의 선정 평가 방안을 제시하였다. 이를 활용하여, 전장관리정보체계의 체계 특성에 부합하는 197개의 시큐어 코딩룰을 선정하였다. 또한 선정된 각 코딩룰 별로 대상 체계에 대한 적용을 위한 우선 순위를 산정하였다.

• BMB Reports
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• 제49권3호
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• pp.149-158
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• 2016

Plants have evolved a vast chemical cornucopia to support their sessile lifestyles. Man has exploited this natural resource since Neolithic times and currently plant-derived chemicals are exploited for a myriad of applications. However, plant sources of most high-value natural products (NPs) are not domesticated and therefore their production cannot be undertaken on an agricultural scale. Further, these plant species are often slow growing, their populations limiting, the concentration of the target molecule highly variable and routinely present at extremely low concentrations. Plant cell and organ culture constitutes a sustainable, controllable and environmentally friendly tool for the industrial production of plant NPs. Further, advances in cell line selection, biotransformation, product secretion, cell permeabilisation, extraction and scale-up, among others, are driving increases in plant NP yields. However, there remain significant obstacles to the commercial synthesis of high-value chemicals from these sources. The relatively recent isolation, culturing and characterisation of cambial meristematic cells (CMCs), provides an emerging platform to circumvent many of these potential difficulties.

• 지식경영연구
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• 제18권4호
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• pp.287-306
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• 2017

This research focus on the effect of developers' participation structure in knowledge creation and knowledge sharing activities in open source software development projects. Based on preferential selection theory, hypotheses of relationship between a developers' concentration of knowledge creation/sharing activities and collaboration performance was derived. To verify the hypotheses, we use the Gini coefficient in the commit contribution of the developers (knowledge creation) and the centralization index in the repository issue network (knowledge sharing network). Using social network analysis, this paper calculates centralization index from developers in the issue boards in each repository based on data from 837 repositories in GitHub, a leading open source software development platform. As a result, instead of all developers creating and sharing knowledge equally, only a few of developers creating and sharing knowledge intensively further improve the performance of the open collaboration. In other words, a few developers predominantly providing commit and actively responding to issues raised from other developers enhance the project performance. The results of this study are expected to be used by developers who manage open source software project as a governance strategy, which could improve the performance of open collaboration.

• Asian-Australasian Journal of Animal Sciences
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• 제25권1호
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• pp.28-32
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• 2012

In the present study, we evaluated the informativeness of SNPs genotyped by the Illumina Bovine SNP50K assay in different cattle breeds. To investigate these on a genome-wide scale, we considered 52,678 SNPs spanning the whole autosomal and X chromosomes in cattle. Our study samples consists of six different cattle breeds. Across the breeds approximately 72 and 6% SNPs were found polymorphic and fixed or close to fix in all the breeds, respectively. The variations in the average minor allele frequency (MAF) were significantly different between the breeds studied. The level of average MAF observed in Hanwoo was significantly lower than the other breeds. Hanwoo breed also displayed the lowest number of polymorphic SNPs across all the chromosomes. More importantly, this study indicated that the Bovine SNP50K assay will have reduced power for genome-wide association studies in Hanwoo as compared to other cattle breeds. Overall, the Bovine SNP50K assay described in this study offer a useful genotyping platform for mapping quantitative trait loci (QTLs) in the cattle breeds. The assay data represent a vast and generally untapped resource to assist the investigation of the complex production traits and the development of marker-assisted selection programs.

• 한국항행학회논문지
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• 제13권1호
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• pp.97-103
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• 2009

본 논문에서는 IEEE 802.15.3 그룹에서 표준화한 HDR -WPAN의 PHY 기술에 대한 구조와 세부 표준 규격을 분석하고, 송 수신부를 설계하여 성능을 분석하였다. 송신부 설계시 전송률에 따라 모드 선택이 가능한 QPSK, DQPSK, 16/32/64QAM-TCM 변조가 모두 가능하도록 설계하였고, 수신부는 DQPSK와 TCM 복호 알고리즘 구현에 중점을 두었다. VHDL을 이용하여 송수신 모뎀을 설계한 후, 실제 보드에 이식하여 MATLAB과 VHDL 시뮬레이터를 이용하여 성능 검증을 위한 연동 실험을 수행하였다. 성능분석 결과 SNR 22dB 이상에서 에러 없는 송수신이 가능함을 확인 하였다.

• 한국정보시스템학회지:정보시스템연구
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• 제26권4호
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• pp.285-301
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• 2017

Purpose In this paper we verified the reliabilities of healthcare-related information provided by various users on the site of Naver Jisikin, a Korean typical search platform. Based on Q&A contents we validated answers' reliabilities to the asked questions about a lung cancer with the help of professors at a medical school. Design/methodology/approach The content analysis includes that the types of questions are classified into symptom/diagnosis, therapy, prognosis, after-management and so on. The answers contains advice, advertisement, oriental medicine, and religion as well as the above 5 question categories. The validation results of medical evidence about each answer show that only 49% among all answers have medical grounds. Findings We classified the medical grounded answers into three levels; high, medium and low. Among all answers we need to find out the answers including advertisement because the answers can be harmful to patients. We found the method to select the answers containing advertisement contents with the help of text mining research. The selection model presents high performance as 84% classification accuracy.

• 천문학회보
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• 제42권2호
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• pp.66.3-66.3
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• 2017

Korea Astronomy and Space Science Institute (KASI) is developing a coronagraph in collaboration with National Aeronautics and Space Administration (NASA) which will be installed on the International Space Station (ISS). The coronagraph can measure speed and temperature by using four filters approximately 400 nm and polarization filter in three different angles, differently with older coronagraphs. For the successful mission, it has development and experiment progress in three phases; total solar eclipse experiment in 2017, balloon experiment in 2019, and the ISS installation in 2021. As a first experiment, we developed a coronagraph without an occulter named with Diagnostic Coronagraph Experiment (DICE) for experiment for filter system and imaging sensor. We designed optics with a field of view from 2.5 to 15 solar radii. It has four filters approximately 400 nm and polarizer to measure speed and velocity of the solar corona. For the selection of filter or polarization angle, it has two mechanism parts; filter wheel assembly and a polarizer wheel assembly. Especially we used Core Flight System (CFS) platform which was developed by NASA, when we develop the coronagraph operation software. It provides us stability, reusability, and compatibility.

• 한국CDE학회논문집
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• 제21권2호
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• pp.159-169
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• 2016

In order to realize the virtual prototyping (VP) of digital products, it is important to provide the people involved in product development with the appropriate visualization and interaction of the products, and the vivid simulation of user interface (UI) behaviors in an interactive 3D virtual environment. In this paper, we propose an approach to web-based 3D virtual experience using Unity and Leap Motion. We adopt Unity as an implementation platform which easily and rapidly implements the visualization of the products and the design and simulation of their UI behaviors, and allows remote users to get an easy access to the virtual environment. Additionally, we combine Leap Motion with Unity to embody natural and immersive interaction using the user's hand gesture. Based on the proposed approach, we have developed a testbed system for web-based 3D virtual experience and applied it for the design evaluation of various digital products. Button selection test was done to investigate the quality of the interaction using Leap Motion, and a preliminary user study was also performed to show the usefulness of the proposed approach.